Written by Tammy Plotner
Sunday, January 1 - Greetings, fellow SkyWatchers! We start our observing year together just before dawn with the brief appearance of Mercury on the eastern skyline. You’ll catch it to the lower left (northeast) of brilliant red Antares.
Friday, December 30, 2011
Wednesday, December 28, 2011
New NASA Probe - The Comet Harpoon
Written by Tammy Plotner
It's not easy to sample a comet. These outer solar system travelers speed around the inner solar system at 241,000 km/h (150,000 mph) - twisting and turning while spewing chunks of ice, dust and debris. To consider landing on one becomes a logistical nightmare, but how about shooting at it? Why not send a mission to rendezvous with these frozen, inhospitable rocks and insert a probe? A method like this could even mean a sample could be taken where a landing would be impossible!
Thanks to the work of scientists at NASA's Goddard Space Flight Center in Greenbelt, Maryland, a new comet "harpoon" is being designed to make comet sample returns not only more efficient, but more detailed.
Roughly the size of a clothes closet, this syringe-like probe stands roughly two meters tall and will be inserted with a cross-bow like arrangement that will contact the surface of the comet. Positioned to fire vertically downward, this bow arrangement consists of a pair of truck leaf springs and 1/2 inch steel cable.. an arrangement which could fire up to a mile if pointed in the wrong direction! When it impacts, an electric winch will draw the bow back into position and eject the harpoon with 1,000 pounds of force at 100 feet per second.
So what would it be like to witness the harpooning of the cosmic whale? An explosive adventure, to be sure. Donald Wegel of NASA Goddard, lead engineer on the project, has been experimenting with the ballista and the core sample box in various impact environments. According to the press release, the resultant impact is something of a combination of rifle report and cannon blast.
"We had to bolt it to the floor, because the recoil made the whole testbed jump after every shot," said Wegel. "We're not sure what we'll encounter on the comet – the surface could be soft and fluffy, mostly made up of dust, or it could be ice mixed with pebbles, or even solid rock. Most likely, there will be areas with different compositions, so we need to design a harpoon that's capable of penetrating a reasonable range of materials. The immediate goal though, is to correlate how much energy is required to penetrate different depths in different materials. What harpoon tip geometries penetrate specific materials best? How does the harpoon mass and cross section affect penetration? The ballista allows us to safely collect this data and use it to size the cannon that will be used on the actual mission."
Studying comet core samples will provide researchers with important information on the original solar nebula and help us to further understand how life may have originated. "One of the most inspiring reasons to go through the trouble and expense of collecting a comet sample is to get a look at the 'primordial ooze' – biomolecules in comets that may have assisted the origin of life," says Wegel. Comet sample return missions - such as the one from Wild 2 - have shown us that that amino acids exist in these inhospitable places, yet may have helped stimulate life here on Earth.
However, there's more to the story than just searching out reasons for life... the biggest being the preservation of life itself. As we know, there's always a possibility that a comet could impact Earth and create an extinction level event. By understanding comet composition, we can get a better grip on what we might need to do should a cataclysmic scenario rear its ugly head. For example, we'd know if a certain type of comet might tend to fragment - or another explode. "So the second major reason to sample comets is to characterize the impact threat," according to Wegel. "We need to understand how they're made so we can come up with the best way to deflect them should any have their sights on us."
"Bringing back a comet sample will also let us analyze it with advanced instruments that won't fit on a spacecraft or haven't been invented yet," adds Dr. Joseph Nuth, a comet expert at NASA Goddard and lead scientist on the project.
If we were to be in a movie, perhaps we might consider getting a comet sample through a method like drilling - but lack of gravity on these small, moving worlds isn't going to allow that to happen. "A spacecraft wouldn't actually land on a comet; it would have to attach itself somehow, probably with some kind of harpoon. So we figured if you have to use a harpoon anyway, you might as well get it to collect your sample," says Nuth.
At the present, the design team is currently hard at work studying the harpoon's reactions to different mediums - and what needs to be done to sample and collect what they might encounter. This isn't easy considering they are working with a basic unknown.
"You can't do this by crunching numbers in a computer, because nobody has done it before -- the data doesn't exist yet," says Nuth. "We need to get data from experiments like this before we can build a computer model. We're working on answers to the most basic questions, like how much powder charge do you need so your harpoon doesn't bounce off or go all the way through the comet. We want to prove the harpoon can penetrate deep enough, collect a sample, decouple from the tip, and retract the sample collection device."
Nothing will be left to chance, however. By creating multiple tips, collection devices and planning for different firing techniques and needs, the team is sure to make the most of their research dollars and the spacecraft that will be available to them. To further assist in their planning, they will also be able to use data from the current Rosetta mission and its lander, Philae, which will hook up with "67P/Churyumov-Gerasimenko" in 2014.
"The Rosetta harpoon is an ingenious design, but it does not collect a sample," says Wegel. "We will piggyback on their work and take it a step further to include a sample-collecting cartridge. It's important to understand the complex internal friction encountered by a hollow, core-sampling harpoon." Even more information will be added from recent NASA mission, OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification, Security -- Regolith Explorer), which is an asteroid sample return mission. It will all add up to some very unique findings and one thing we do know is...
"Admiral? Thar' be whales here..."
It's not easy to sample a comet. These outer solar system travelers speed around the inner solar system at 241,000 km/h (150,000 mph) - twisting and turning while spewing chunks of ice, dust and debris. To consider landing on one becomes a logistical nightmare, but how about shooting at it? Why not send a mission to rendezvous with these frozen, inhospitable rocks and insert a probe? A method like this could even mean a sample could be taken where a landing would be impossible!
Thanks to the work of scientists at NASA's Goddard Space Flight Center in Greenbelt, Maryland, a new comet "harpoon" is being designed to make comet sample returns not only more efficient, but more detailed.
Roughly the size of a clothes closet, this syringe-like probe stands roughly two meters tall and will be inserted with a cross-bow like arrangement that will contact the surface of the comet. Positioned to fire vertically downward, this bow arrangement consists of a pair of truck leaf springs and 1/2 inch steel cable.. an arrangement which could fire up to a mile if pointed in the wrong direction! When it impacts, an electric winch will draw the bow back into position and eject the harpoon with 1,000 pounds of force at 100 feet per second.
So what would it be like to witness the harpooning of the cosmic whale? An explosive adventure, to be sure. Donald Wegel of NASA Goddard, lead engineer on the project, has been experimenting with the ballista and the core sample box in various impact environments. According to the press release, the resultant impact is something of a combination of rifle report and cannon blast.
"We had to bolt it to the floor, because the recoil made the whole testbed jump after every shot," said Wegel. "We're not sure what we'll encounter on the comet – the surface could be soft and fluffy, mostly made up of dust, or it could be ice mixed with pebbles, or even solid rock. Most likely, there will be areas with different compositions, so we need to design a harpoon that's capable of penetrating a reasonable range of materials. The immediate goal though, is to correlate how much energy is required to penetrate different depths in different materials. What harpoon tip geometries penetrate specific materials best? How does the harpoon mass and cross section affect penetration? The ballista allows us to safely collect this data and use it to size the cannon that will be used on the actual mission."
Studying comet core samples will provide researchers with important information on the original solar nebula and help us to further understand how life may have originated. "One of the most inspiring reasons to go through the trouble and expense of collecting a comet sample is to get a look at the 'primordial ooze' – biomolecules in comets that may have assisted the origin of life," says Wegel. Comet sample return missions - such as the one from Wild 2 - have shown us that that amino acids exist in these inhospitable places, yet may have helped stimulate life here on Earth.
However, there's more to the story than just searching out reasons for life... the biggest being the preservation of life itself. As we know, there's always a possibility that a comet could impact Earth and create an extinction level event. By understanding comet composition, we can get a better grip on what we might need to do should a cataclysmic scenario rear its ugly head. For example, we'd know if a certain type of comet might tend to fragment - or another explode. "So the second major reason to sample comets is to characterize the impact threat," according to Wegel. "We need to understand how they're made so we can come up with the best way to deflect them should any have their sights on us."
"Bringing back a comet sample will also let us analyze it with advanced instruments that won't fit on a spacecraft or haven't been invented yet," adds Dr. Joseph Nuth, a comet expert at NASA Goddard and lead scientist on the project.
If we were to be in a movie, perhaps we might consider getting a comet sample through a method like drilling - but lack of gravity on these small, moving worlds isn't going to allow that to happen. "A spacecraft wouldn't actually land on a comet; it would have to attach itself somehow, probably with some kind of harpoon. So we figured if you have to use a harpoon anyway, you might as well get it to collect your sample," says Nuth.
At the present, the design team is currently hard at work studying the harpoon's reactions to different mediums - and what needs to be done to sample and collect what they might encounter. This isn't easy considering they are working with a basic unknown.
"You can't do this by crunching numbers in a computer, because nobody has done it before -- the data doesn't exist yet," says Nuth. "We need to get data from experiments like this before we can build a computer model. We're working on answers to the most basic questions, like how much powder charge do you need so your harpoon doesn't bounce off or go all the way through the comet. We want to prove the harpoon can penetrate deep enough, collect a sample, decouple from the tip, and retract the sample collection device."
Nothing will be left to chance, however. By creating multiple tips, collection devices and planning for different firing techniques and needs, the team is sure to make the most of their research dollars and the spacecraft that will be available to them. To further assist in their planning, they will also be able to use data from the current Rosetta mission and its lander, Philae, which will hook up with "67P/Churyumov-Gerasimenko" in 2014.
"The Rosetta harpoon is an ingenious design, but it does not collect a sample," says Wegel. "We will piggyback on their work and take it a step further to include a sample-collecting cartridge. It's important to understand the complex internal friction encountered by a hollow, core-sampling harpoon." Even more information will be added from recent NASA mission, OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification, Security -- Regolith Explorer), which is an asteroid sample return mission. It will all add up to some very unique findings and one thing we do know is...
"Admiral? Thar' be whales here..."
Monday, December 26, 2011
Product Spotlight - The Galileoscope
Written by Tammy Plotner
Over four hundred years ago, Galileo pointed his refractor telescope towards the night sky and forever changed the way mankind thinks of astronomy. Wouldn't it be wonderful to have shared the eyepiece with Galileo - or to have been there to watch as he assembled one of those very first telescopes? Now you can...
While we can't step back in time, we can bring all the excitement and learning to you in a hands-on optic kit which will allow you to assemble a Galileo-like refractor telescope from the ground up. A dedicated team of researchers, astronomers and educators designed the Galileoscope Telescope Kit to be one of the most ultimate tools you'll ever encounter. It's more than just a kit... It's a learning experience.
The Galileoscope Telescope Kit achromatic optics include a 50-mm-diameter objective lens of focal length 500 mm, an eyepiece of focal length 20 mm (magnification 25x), and a 2x Barlow lens (yielding 50x when used with the supplied eyepiece). The Galileoscope accepts almost any optical accessory that has a standard 1¼-inch (31¾-mm) barrel, and it attaches to virtually every tripod made or distributed anywhere in the world.
While the facts and figures are great, it's what happens when you use it that counts the most. By inspection of each individual piece and how they connect together, you (and your audience) are able to grasp the concept of what makes a refractor telescope work. What's more, it can be disassembled and reassembled over and over again, so the learning doesn't stop with a single construction - or a single audience!
The Galileoscope Telescope Kit is perfect for educators of all types - home school, scouts, science classes, adult astronomy outreach and more! Even though it is inexpensive, it was built with durability in mind and - with proper care - will provide years of service. It's a very cool tool that deserves a place in every classroom and astronomy club!
Over four hundred years ago, Galileo pointed his refractor telescope towards the night sky and forever changed the way mankind thinks of astronomy. Wouldn't it be wonderful to have shared the eyepiece with Galileo - or to have been there to watch as he assembled one of those very first telescopes? Now you can...
While we can't step back in time, we can bring all the excitement and learning to you in a hands-on optic kit which will allow you to assemble a Galileo-like refractor telescope from the ground up. A dedicated team of researchers, astronomers and educators designed the Galileoscope Telescope Kit to be one of the most ultimate tools you'll ever encounter. It's more than just a kit... It's a learning experience.
The Galileoscope Telescope Kit achromatic optics include a 50-mm-diameter objective lens of focal length 500 mm, an eyepiece of focal length 20 mm (magnification 25x), and a 2x Barlow lens (yielding 50x when used with the supplied eyepiece). The Galileoscope accepts almost any optical accessory that has a standard 1¼-inch (31¾-mm) barrel, and it attaches to virtually every tripod made or distributed anywhere in the world.
While the facts and figures are great, it's what happens when you use it that counts the most. By inspection of each individual piece and how they connect together, you (and your audience) are able to grasp the concept of what makes a refractor telescope work. What's more, it can be disassembled and reassembled over and over again, so the learning doesn't stop with a single construction - or a single audience!
The Galileoscope Telescope Kit is perfect for educators of all types - home school, scouts, science classes, adult astronomy outreach and more! Even though it is inexpensive, it was built with durability in mind and - with proper care - will provide years of service. It's a very cool tool that deserves a place in every classroom and astronomy club!
Friday, December 23, 2011
Weekly SkyWatcher's Forecast - December 24-31, 2011
Written by Tammy Plotner
Friday, December 24 - Today in 1968, Apollo 8 became the first manned spacecraft to orbit the Moon. Until this date, no man had seen with his own eyes what lay beyond. Frank Borman, James Lovell and William Anders were to become the first to directly view the "dark side" and the first to witness earthrise over the Moon. As the days ahead bring the terminator around to the eastern limb, let your mind take flight to the distant orb and enjoy its landscape as the shadows take on new angles and old features become new again.
"And from the crew of Apollo 8, we close, with good night, good luck, a Merry Christmas, and God bless all of you, all of you on the good Earth." (Astronaut Frank Borman)
‘Twas the night before Christmas and all through the house, not a creature was stirring…except for the mouse with the telescope who wants to see a multiple star system! Why don’t we join him tonight and have a look at very nice, and easily resolved, Sigma Orionis.
This particular system is easily found without a map. By identifying the three “belt” stars of Orion, go to the easternmost – Alnitak. Sigma is the first star south of it. In the telescope you will find a beautiful combination of four stars. The 3.8 magnitude white primary commands attention. With a designation of “A/B,” this super-massive and extremely bright pair is far too close (about 100 AU apart) to be split with a small scope. Looking 11″ to the southwest, you will discover the 10th magnitude white “C” star and you will see the 7.2 magnitude red “D” star 13″ to the east. Further away yet at a distance of 42″ to the east-northeast is the 6.5 magnitude blue “E” star. Sharp-eyed observers will also note another multiple system in the same field of view to the northwest. This is Struve 761. As an “all white” system of similar magnitudes, you will see two residing east/west of each other and the third companion to the north. What we are looking at is a system that is about 1,500 light years away from us in the rich, star-forming region of Orion. Give that mouse a piece of cheese!
Saturday, December 25 - Wishing you all the very best for the Christmas season! Like a present, Sir Isaac Newton was born on this day 1642 - Newton was the British "inventor" of calculus and a huge amount of what we now consider modern classical physics. Even young children are aware of his simple laws of motion and gravity. It wasn't until the time of Einstein until things changed!
In keeping with the season, tonight's astronomical object is a celebration of both starlight and asterism. Located 10 degrees east of Betelgeuse (RA 06 41 00.00 Dec +09 53 -0.0), NGC 2264 will be a challenging object thanks to the Moon. Also known as the "Christmas Tree Cluster," this bright asterism of approximately 20 bright stars and over 100 fainter ones is embroiled in a faint nebula that will be lost to bright skies, leaving only the delightful Christmas tree shape adorned with stars.
The very brightest of these stars, S Monocerotis, is 5th magnitude and will show clearly in the finderscope, and will be seen as a double at magnification. Steady skies will reveal that the "star" at the top of our "tree" is also a visual double. Many of the stars will also appear to have companions, as well as tints of silver as gold. The visual effect of this splendid open cluster is well worth the challenge it presents.
While you’re out tonight, be sure to enjoy the close pairing of Jupiter and the Moon. For observers in south Africa and southern South America this is an occultation event. Happy Holidays!
Sunday, December 26 - The slender crescent Moon will appear along the western horizon early this evening, but we're going to run ahead of it tonight and enjoy some studies in Auriga! Looking roughly like a pentagon in shape, start by identifying the brightest of these stars - Capella. Due south of it is the second brightest star, El Nath. By aiming binoculars at El Nath, go north about one-third the distance between the two and enjoy all the stars!
You will note two very conspicuous clusters of stars in this area, and so did Le Gentil in 1749. Binoculars will reveal the pair in the same field, as will telescopes using lowest power. The dimmest of these is M38, and it will appear vaguely cruciform in shape. At roughly 4200 light-years away, larger aperture will be needed to resolve the 100 or so fainter members. About two and a half degrees to the southeast you will see the much brighter M36. More easily resolved in binoculars and small scopes, this "jewel box" galactic cluster is quite young - and about 100 light-years closer!
Monday, December 27 - Born today in 1571 was Johannes Kepler - Danish astronomer and assistant to Tycho Brahe. Kepler used Brahe's copious notes of Mars' positions to help formulate his three laws of planetary motion. These laws are still in use today.
Before the Moon begins to interfere with deep sky studies, we still have time to set our sights about halfway between Theta Aurigae and El Nath. Our study object will be the open cluster M37. Apparently discovered by Messier himself in 1764, this galactic cluster will appear almost nebula-like to binoculars and very small telescopes - but comes to perfect resolution with larger instruments. At around 4700 light-years away, and spanning a massive 25 light-years, M37 is often billed as the finest of the three Aurigan opens for bigger scopes. Offering beautiful resolvability, this one contains around 150 members down to magnitude 12, and has a total population in excess of 500.
What makes it unique? As you view, you will note the presence of several red giants. For the most part, open clusters are comprised of stars that are all about the same age, but the brightest star in M37 appears orange in color and not blue! So what exactly is going on in here? Apparently some of these big, bright stars have evolved much faster - consuming their fuel at an incredible rate. Other stars in this cluster are still quite young on a cosmic scale, yet they all left the "nursery" at the same time! In theory, this allows us to judge the relative age of open clusters. For example, M36 is around 30 million years old and M38 about 40, but the presence of the red giants in M37 puts its estimated age at 150 million years! Just awesome...
Tuesday, December 28 - Today we celebrate the birth of Arthur S. Eddington. Born in 1882, Eddington was a British theoretical astrophysicist whose work was fundamental to interpreting and explaining stellar nature. He also coined the phrase "expanding universe" to refer to the mutual recession of the galaxies.
Tonight it’s going to be very hard to ignore the Moon, so why don’t we start by studying it and picking up another lunar club challenge? Your mission is to locate crater Petavius along the southeast shore of Mare Fecunditatis and have a look at the Petavius Wall… While you’re admiring Petavius and its branching rima, keep in mind this 80 kilometer long crack is a buckle in the lava flow across the crater floor. Now look along the terminator for the long, dark runnel which is often considered to be the Petavius Wall but is actually the fascinating crater Palitzsch. This 41 kilometer wide crater is confluent with a 110 kilometer long valley that is outstanding at this phase!
As soon as the Moon sets, let's enjoy the early dark skies and go to our maps west of M36 and M38 to identify AE Aurigae. As an unusual variable, AE is normally around 6th magnitude and resides approximately 1600 light-years distant. The beauty in this region is not particularly the star itself but the faint nebula in which it resides. Known as IC 405, this is an area of mostly dust and very little gas. What makes this view so entertaining is that we are looking at a "runaway" star. It is believed that AE originated in the M42 region in Orion. Cruising along at a very respectable speed of 130 kilometers per second, AE flew the "stellar nest" some 2.7 million years ago! Although IC 405 is not directly related to AE, there is evidence within the nebula that areas have been cleared of their dust by the rapid northward motion of the star. AE's hot, blue illumination and high energy photons fuel what little gas is contained within the region, and its light reflects off the surrounding dust as well. Although we cannot "see" with our eyes like a photograph, together this pair makes an outstanding view for the small backyard telescope, and it is known as "The Flaming Star."
Wednesday, December 29 - As the skies darken, we’ll venture to the lunar surface near previous study Posidonius to have a look at the incredible Serpentine Ridge. Known more properly as Dorsa Smirnov, it meanders for 130 kilometers north to south across Mare Serenitatis. Can you spot tiny the crater Very in its center?
Before the Moon interferes too much, this would be a great opportunity to locate an easy Messier object - M34. If you remember our previous study stars Almach and Algol, you're halfway there. Draw an imaginary line between them and look with your binoculars or finder scope just a shade north of center. In binoculars, M34 will show around a dozen fainter stars clustered together, and perhaps a dozen more scattered around the field. Small telescopes at low power will appreciate M34 for its resolvability and the distinctive orange star in the center. Larger aperture scopes will need to stay at lowest power to appreciate the 18 light-year span of this 100 million year old cluster, but take the time to power up and study. You will find many challenging doubles inside!
Thursday, December 30 - So… Are you ready to do a lunar walk for a challenge crater we haven’t listed yet? Then look to the northwest shore of Mare Serenitatis for the pair of Aristoteles and Eudoxus. What’s that? You see more? Then mark your notes for Eudoxus and let’s have a look at many other studies you may not have noted yet! The Moon will set shortly, and leave us with an opportunity to head for another northern gem, M76.
Located in western Perseus just slightly less than one degree north-northwest of Phi, M76 is often referred to as "The Little Dumbbell." Originally discovered by Messier's assistant Mechain in September of 1780, Charles didn't get around to cataloging it for another six weeks. What a shame it took him so long to view this fine planetary nebula! Its central star is one of the hottest known, but its resemblance to M27 is what makes it so fascinating. Looking very much like a miniaturization of the much larger M27, M76 is rather faint at magnitude 11, but is quite achievable in scopes of 114mm in aperture or larger. It is small, but its irregular shape makes this planetary nebula a real "class act!"
For our Southern Hemisphere friends, get thee out there and view Eta Carinae! First recorded by Halley in 1677, this nebular variable star left even the great Sir John Herschel at a loss to describe its true beauty and complexities. This "slow nova" is filled with all the wonders that we "northerners" can only dream about...
Friday, December 31 - Today is the birthday of Robert G. Aitken. Born in 1864, Aitken was a prolific American observer who discovered and catalogued more than 3100 double and binary stars. The Moon will be around much later tonight, but the year 2011 is just about ended. Try celebrating in a unique and inspiring way! Go observing...
In the hours before midnight, you could take a cosmic journey that spans millions of light-years. In the northern hemisphere, visit with the Andromeda Galaxy again - or the Small and Large Magellanic Clouds if you live in the South. Feast your eyes on vast and wondrous displays of stars like the "Double Cluster" in Perseus, or the "Jewel Box" - the Kappa Crucis star cluster. Rejoice in the birth of new stars by voyaging to M42 - the Orion Nebula... And remember the old by returning to M1 - the Crab Nebula. Perhaps the ISS will make a pass over your area tonight, or maybe only a single star will shine through your cloudy sky. It may be something as spectacular as watching a meteor go down in a blaze of glory, or as quiet and contemplative as watching the Moon rise as the year ends.
Now take a moment to look up at the stars and think about all the billions of years that they have been in the making and all the time that it has taken for the light to reach us. Salute! Our observing year has been wonderful together and I'll look for you under the stars! May all your journeys be at light speed…
Friday, December 24 - Today in 1968, Apollo 8 became the first manned spacecraft to orbit the Moon. Until this date, no man had seen with his own eyes what lay beyond. Frank Borman, James Lovell and William Anders were to become the first to directly view the "dark side" and the first to witness earthrise over the Moon. As the days ahead bring the terminator around to the eastern limb, let your mind take flight to the distant orb and enjoy its landscape as the shadows take on new angles and old features become new again. "And from the crew of Apollo 8, we close, with good night, good luck, a Merry Christmas, and God bless all of you, all of you on the good Earth." (Astronaut Frank Borman)
‘Twas the night before Christmas and all through the house, not a creature was stirring…except for the mouse with the telescope who wants to see a multiple star system! Why don’t we join him tonight and have a look at very nice, and easily resolved, Sigma Orionis.
This particular system is easily found without a map. By identifying the three “belt” stars of Orion, go to the easternmost – Alnitak. Sigma is the first star south of it. In the telescope you will find a beautiful combination of four stars. The 3.8 magnitude white primary commands attention. With a designation of “A/B,” this super-massive and extremely bright pair is far too close (about 100 AU apart) to be split with a small scope. Looking 11″ to the southwest, you will discover the 10th magnitude white “C” star and you will see the 7.2 magnitude red “D” star 13″ to the east. Further away yet at a distance of 42″ to the east-northeast is the 6.5 magnitude blue “E” star. Sharp-eyed observers will also note another multiple system in the same field of view to the northwest. This is Struve 761. As an “all white” system of similar magnitudes, you will see two residing east/west of each other and the third companion to the north. What we are looking at is a system that is about 1,500 light years away from us in the rich, star-forming region of Orion. Give that mouse a piece of cheese!
Saturday, December 25 - Wishing you all the very best for the Christmas season! Like a present, Sir Isaac Newton was born on this day 1642 - Newton was the British "inventor" of calculus and a huge amount of what we now consider modern classical physics. Even young children are aware of his simple laws of motion and gravity. It wasn't until the time of Einstein until things changed!
In keeping with the season, tonight's astronomical object is a celebration of both starlight and asterism. Located 10 degrees east of Betelgeuse (RA 06 41 00.00 Dec +09 53 -0.0), NGC 2264 will be a challenging object thanks to the Moon. Also known as the "Christmas Tree Cluster," this bright asterism of approximately 20 bright stars and over 100 fainter ones is embroiled in a faint nebula that will be lost to bright skies, leaving only the delightful Christmas tree shape adorned with stars.
The very brightest of these stars, S Monocerotis, is 5th magnitude and will show clearly in the finderscope, and will be seen as a double at magnification. Steady skies will reveal that the "star" at the top of our "tree" is also a visual double. Many of the stars will also appear to have companions, as well as tints of silver as gold. The visual effect of this splendid open cluster is well worth the challenge it presents.
While you’re out tonight, be sure to enjoy the close pairing of Jupiter and the Moon. For observers in south Africa and southern South America this is an occultation event. Happy Holidays!
Sunday, December 26 - The slender crescent Moon will appear along the western horizon early this evening, but we're going to run ahead of it tonight and enjoy some studies in Auriga! Looking roughly like a pentagon in shape, start by identifying the brightest of these stars - Capella. Due south of it is the second brightest star, El Nath. By aiming binoculars at El Nath, go north about one-third the distance between the two and enjoy all the stars!
You will note two very conspicuous clusters of stars in this area, and so did Le Gentil in 1749. Binoculars will reveal the pair in the same field, as will telescopes using lowest power. The dimmest of these is M38, and it will appear vaguely cruciform in shape. At roughly 4200 light-years away, larger aperture will be needed to resolve the 100 or so fainter members. About two and a half degrees to the southeast you will see the much brighter M36. More easily resolved in binoculars and small scopes, this "jewel box" galactic cluster is quite young - and about 100 light-years closer!
Monday, December 27 - Born today in 1571 was Johannes Kepler - Danish astronomer and assistant to Tycho Brahe. Kepler used Brahe's copious notes of Mars' positions to help formulate his three laws of planetary motion. These laws are still in use today.
Before the Moon begins to interfere with deep sky studies, we still have time to set our sights about halfway between Theta Aurigae and El Nath. Our study object will be the open cluster M37. Apparently discovered by Messier himself in 1764, this galactic cluster will appear almost nebula-like to binoculars and very small telescopes - but comes to perfect resolution with larger instruments. At around 4700 light-years away, and spanning a massive 25 light-years, M37 is often billed as the finest of the three Aurigan opens for bigger scopes. Offering beautiful resolvability, this one contains around 150 members down to magnitude 12, and has a total population in excess of 500.
What makes it unique? As you view, you will note the presence of several red giants. For the most part, open clusters are comprised of stars that are all about the same age, but the brightest star in M37 appears orange in color and not blue! So what exactly is going on in here? Apparently some of these big, bright stars have evolved much faster - consuming their fuel at an incredible rate. Other stars in this cluster are still quite young on a cosmic scale, yet they all left the "nursery" at the same time! In theory, this allows us to judge the relative age of open clusters. For example, M36 is around 30 million years old and M38 about 40, but the presence of the red giants in M37 puts its estimated age at 150 million years! Just awesome...
Tuesday, December 28 - Today we celebrate the birth of Arthur S. Eddington. Born in 1882, Eddington was a British theoretical astrophysicist whose work was fundamental to interpreting and explaining stellar nature. He also coined the phrase "expanding universe" to refer to the mutual recession of the galaxies.
Tonight it’s going to be very hard to ignore the Moon, so why don’t we start by studying it and picking up another lunar club challenge? Your mission is to locate crater Petavius along the southeast shore of Mare Fecunditatis and have a look at the Petavius Wall… While you’re admiring Petavius and its branching rima, keep in mind this 80 kilometer long crack is a buckle in the lava flow across the crater floor. Now look along the terminator for the long, dark runnel which is often considered to be the Petavius Wall but is actually the fascinating crater Palitzsch. This 41 kilometer wide crater is confluent with a 110 kilometer long valley that is outstanding at this phase!
As soon as the Moon sets, let's enjoy the early dark skies and go to our maps west of M36 and M38 to identify AE Aurigae. As an unusual variable, AE is normally around 6th magnitude and resides approximately 1600 light-years distant. The beauty in this region is not particularly the star itself but the faint nebula in which it resides. Known as IC 405, this is an area of mostly dust and very little gas. What makes this view so entertaining is that we are looking at a "runaway" star. It is believed that AE originated in the M42 region in Orion. Cruising along at a very respectable speed of 130 kilometers per second, AE flew the "stellar nest" some 2.7 million years ago! Although IC 405 is not directly related to AE, there is evidence within the nebula that areas have been cleared of their dust by the rapid northward motion of the star. AE's hot, blue illumination and high energy photons fuel what little gas is contained within the region, and its light reflects off the surrounding dust as well. Although we cannot "see" with our eyes like a photograph, together this pair makes an outstanding view for the small backyard telescope, and it is known as "The Flaming Star."
Wednesday, December 29 - As the skies darken, we’ll venture to the lunar surface near previous study Posidonius to have a look at the incredible Serpentine Ridge. Known more properly as Dorsa Smirnov, it meanders for 130 kilometers north to south across Mare Serenitatis. Can you spot tiny the crater Very in its center?
Before the Moon interferes too much, this would be a great opportunity to locate an easy Messier object - M34. If you remember our previous study stars Almach and Algol, you're halfway there. Draw an imaginary line between them and look with your binoculars or finder scope just a shade north of center. In binoculars, M34 will show around a dozen fainter stars clustered together, and perhaps a dozen more scattered around the field. Small telescopes at low power will appreciate M34 for its resolvability and the distinctive orange star in the center. Larger aperture scopes will need to stay at lowest power to appreciate the 18 light-year span of this 100 million year old cluster, but take the time to power up and study. You will find many challenging doubles inside!
Thursday, December 30 - So… Are you ready to do a lunar walk for a challenge crater we haven’t listed yet? Then look to the northwest shore of Mare Serenitatis for the pair of Aristoteles and Eudoxus. What’s that? You see more? Then mark your notes for Eudoxus and let’s have a look at many other studies you may not have noted yet! The Moon will set shortly, and leave us with an opportunity to head for another northern gem, M76.
Located in western Perseus just slightly less than one degree north-northwest of Phi, M76 is often referred to as "The Little Dumbbell." Originally discovered by Messier's assistant Mechain in September of 1780, Charles didn't get around to cataloging it for another six weeks. What a shame it took him so long to view this fine planetary nebula! Its central star is one of the hottest known, but its resemblance to M27 is what makes it so fascinating. Looking very much like a miniaturization of the much larger M27, M76 is rather faint at magnitude 11, but is quite achievable in scopes of 114mm in aperture or larger. It is small, but its irregular shape makes this planetary nebula a real "class act!"
For our Southern Hemisphere friends, get thee out there and view Eta Carinae! First recorded by Halley in 1677, this nebular variable star left even the great Sir John Herschel at a loss to describe its true beauty and complexities. This "slow nova" is filled with all the wonders that we "northerners" can only dream about...
Friday, December 31 - Today is the birthday of Robert G. Aitken. Born in 1864, Aitken was a prolific American observer who discovered and catalogued more than 3100 double and binary stars. The Moon will be around much later tonight, but the year 2011 is just about ended. Try celebrating in a unique and inspiring way! Go observing...
In the hours before midnight, you could take a cosmic journey that spans millions of light-years. In the northern hemisphere, visit with the Andromeda Galaxy again - or the Small and Large Magellanic Clouds if you live in the South. Feast your eyes on vast and wondrous displays of stars like the "Double Cluster" in Perseus, or the "Jewel Box" - the Kappa Crucis star cluster. Rejoice in the birth of new stars by voyaging to M42 - the Orion Nebula... And remember the old by returning to M1 - the Crab Nebula. Perhaps the ISS will make a pass over your area tonight, or maybe only a single star will shine through your cloudy sky. It may be something as spectacular as watching a meteor go down in a blaze of glory, or as quiet and contemplative as watching the Moon rise as the year ends.
Now take a moment to look up at the stars and think about all the billions of years that they have been in the making and all the time that it has taken for the light to reach us. Salute! Our observing year has been wonderful together and I'll look for you under the stars! May all your journeys be at light speed…
Wednesday, December 21, 2011
In The Still Of The Night... Listening To The "Heartbeat" Of A Tiny Black Hole
Written by: Tammy Plotner
Is everything quiet in deep space? Not hardly. It's a place jammed with noises of all kinds. So much noise, in fact, that it could be quite difficult to pick up a faint signature of something small... something like the smallest black hole known. Thanks to NASA's Rossi X-ray Timing Explorer (RXTE) , an international team of astronomers have found the pulse they were looking for and it's a pattern that's only been seen in one other black hole system. Its name is IGR J17091-3624 and it's a binary system which consists of a normal star and a black hole with a mass that measures only about three times solar. In theoretical terms, that's right at the edge where possibility of being a black hole begins.
Here's the picture... In this binary system, escaping gas from the "normal" star flows across space in the direction of the black hole. This action creates a disk where friction heats it to millions of degrees - releasing X-rays. Periodic changes in the strength of the X-ray emissions point towards the actions taking place within the gas disk. Scientists theorize that fast changes occur at the event horizon... the point of no return.
IGR J17091-3624 was discovered when it went into outburst in 2003. Current observations have it becoming active every few years and its most recent flare began in February of this year and has been kicking up cosmic dust ever since. Observations place it in the general direction of Scorpius, but astronomers aren't sure of an exact distance - somewhere between 16,00 light years to more than 65,000. However, IGR J17091-3624 isn't absolutely alone in its unique changes. Black hole binary, GRS 1915+105, also displays a number of well-ordered rhythms, too.
This animation compares the X-ray 'heartbeats' of GRS 1915 and IGR J17091, two black holes that ingest gas from companion stars. GRS 1915 has nearly five times the mass of IGR J17091, which at three solar masses may be the smallest black hole known. A fly-through relates the heartbeats to hypothesized changes in the black hole's jet and disk. Credit: NASA/Goddard Space Flight Center/CI Lab
"We think that most of these patterns represent cycles of accumulation and ejection in an unstable disk, and we now see seven of them in IGR J17091," said Tomaso Belloni at Brera Observatory in Merate, Italy. "Identifying these signatures in a second black hole system is very exciting."
Binary GRS 1915 has some very cool characteristics. Right now astronomers have observed jets blasting out in opposite directions cruising along at 98% the speed of light. These originate at the event horizon where strong magnetic fields fuel them and each pulsation matches the occurrence of the jets. By observing the X-ray spectrum with RXTE, researchers have discovered the interior of the disk creates enough radiation to halt the gas flow - an outward wind which negates the inward flow - and shuts down activity. As a result, the inner disk glows hot and bright, eliminating itself as it flows toward the black hole and kick starts the jet activity again. It's a process that happens in as little as 40 seconds!
Right now astronomers aren't able to prove that IGR J17091 has a particle jet, but the regular pulsations indicate it. Records show this "heartbeat" occurs about every five seconds - about 8 times faster than its counterpart and some 20 times more faint. Numbers like this would make it a very tiny black hole.
"Just as the heart rate of a mouse is faster than an elephant's, the heartbeat signals from these black holes scale according to their masses," said Diego Altamirano, an astrophysicist at the University of Amsterdam in The Netherlands and lead author of a paper describing the findings in the November 4 issue of The Astrophysical Journal Letters. It's just the beginning of a full scale program involving RXTE to compare information from both black holes. Even more detailed data will be added from NASA's Swift satellite and XMM-Newton, too.
"Until this study, GRS 1915 was essentially a one-off, and there's only so much we can understand from a single example," said Tod Strohmayer, the project scientist for RXTE at NASA's Goddard Space Flight Center in Greenbelt, Md. "Now, with a second system exhibiting similar types of variability, we really can begin to test how well we understand what happens at the brink of a black hole."
Original Story Source: NASA Mission News.
Is everything quiet in deep space? Not hardly. It's a place jammed with noises of all kinds. So much noise, in fact, that it could be quite difficult to pick up a faint signature of something small... something like the smallest black hole known. Thanks to NASA's Rossi X-ray Timing Explorer (RXTE) , an international team of astronomers have found the pulse they were looking for and it's a pattern that's only been seen in one other black hole system. Its name is IGR J17091-3624 and it's a binary system which consists of a normal star and a black hole with a mass that measures only about three times solar. In theoretical terms, that's right at the edge where possibility of being a black hole begins.
Here's the picture... In this binary system, escaping gas from the "normal" star flows across space in the direction of the black hole. This action creates a disk where friction heats it to millions of degrees - releasing X-rays. Periodic changes in the strength of the X-ray emissions point towards the actions taking place within the gas disk. Scientists theorize that fast changes occur at the event horizon... the point of no return.
IGR J17091-3624 was discovered when it went into outburst in 2003. Current observations have it becoming active every few years and its most recent flare began in February of this year and has been kicking up cosmic dust ever since. Observations place it in the general direction of Scorpius, but astronomers aren't sure of an exact distance - somewhere between 16,00 light years to more than 65,000. However, IGR J17091-3624 isn't absolutely alone in its unique changes. Black hole binary, GRS 1915+105, also displays a number of well-ordered rhythms, too.
This animation compares the X-ray 'heartbeats' of GRS 1915 and IGR J17091, two black holes that ingest gas from companion stars. GRS 1915 has nearly five times the mass of IGR J17091, which at three solar masses may be the smallest black hole known. A fly-through relates the heartbeats to hypothesized changes in the black hole's jet and disk. Credit: NASA/Goddard Space Flight Center/CI Lab
"We think that most of these patterns represent cycles of accumulation and ejection in an unstable disk, and we now see seven of them in IGR J17091," said Tomaso Belloni at Brera Observatory in Merate, Italy. "Identifying these signatures in a second black hole system is very exciting."
Binary GRS 1915 has some very cool characteristics. Right now astronomers have observed jets blasting out in opposite directions cruising along at 98% the speed of light. These originate at the event horizon where strong magnetic fields fuel them and each pulsation matches the occurrence of the jets. By observing the X-ray spectrum with RXTE, researchers have discovered the interior of the disk creates enough radiation to halt the gas flow - an outward wind which negates the inward flow - and shuts down activity. As a result, the inner disk glows hot and bright, eliminating itself as it flows toward the black hole and kick starts the jet activity again. It's a process that happens in as little as 40 seconds!
Right now astronomers aren't able to prove that IGR J17091 has a particle jet, but the regular pulsations indicate it. Records show this "heartbeat" occurs about every five seconds - about 8 times faster than its counterpart and some 20 times more faint. Numbers like this would make it a very tiny black hole.
"Just as the heart rate of a mouse is faster than an elephant's, the heartbeat signals from these black holes scale according to their masses," said Diego Altamirano, an astrophysicist at the University of Amsterdam in The Netherlands and lead author of a paper describing the findings in the November 4 issue of The Astrophysical Journal Letters. It's just the beginning of a full scale program involving RXTE to compare information from both black holes. Even more detailed data will be added from NASA's Swift satellite and XMM-Newton, too.
"Until this study, GRS 1915 was essentially a one-off, and there's only so much we can understand from a single example," said Tod Strohmayer, the project scientist for RXTE at NASA's Goddard Space Flight Center in Greenbelt, Md. "Now, with a second system exhibiting similar types of variability, we really can begin to test how well we understand what happens at the brink of a black hole."
Original Story Source: NASA Mission News.
Monday, December 19, 2011
Product Spotlight - The Celestron Power Tank
Written by Tammy Plotner
For those who have a battery-operated "GoTo" telescope, you know the scene. Even the best of them eat batteries! Sure, an AC converter does help, but what happens when you're in the field where you can't use an electrical outlet and hooking up with your car battery and a DC line isn't an option, either? Well, then you have to rely on battery power... And here's some battery power that won't let you down.
The Celestron 12V 7AH Power Tank is hefty and reliable. This unique power source allows you to connect your telescope via the DC (car auxiliary port) cable and gives you all the juice you'll need for a full night's observing and more. Just park it between your tripod legs, hook up your power line and you're good to go.
Not only does it power your telescope, but a whole lot more. There are three 5mm pin-jack outlets for operating accessories (1 amp max)...a 3V, a 6V and a 9V. There is a built-in flashlight with a red filter that comes in handy during after-dark set-ups! Add to that an 800,000 candle-power halogen emergency spotlight built into the unit. It is certainly not for star parties, but if you leave the Power Tank in your car or someplace accessible in your home, the bright spotlight could be a lifesaver.
Re-chargeable? You bet. It comes with all the necessary gear to just plug it into any standard outlet to revive. One very cool feature is that it can also take a charge from your car, so if you forget at home, you can always charge while driving to a star party or to your remote location. For safety's sake, it will even add a power boost to a weak car battery, so it makes a great emergency tool. What's more, this product is Celestron durable. That means you're going to have it around and doing its job long after the warranty has expired.
Interested? You'll find the Celestron 12V 7AH Power Tank at OPT - and at a price you'll really like.
For those who have a battery-operated "GoTo" telescope, you know the scene. Even the best of them eat batteries! Sure, an AC converter does help, but what happens when you're in the field where you can't use an electrical outlet and hooking up with your car battery and a DC line isn't an option, either? Well, then you have to rely on battery power... And here's some battery power that won't let you down.
The Celestron 12V 7AH Power Tank is hefty and reliable. This unique power source allows you to connect your telescope via the DC (car auxiliary port) cable and gives you all the juice you'll need for a full night's observing and more. Just park it between your tripod legs, hook up your power line and you're good to go.
Not only does it power your telescope, but a whole lot more. There are three 5mm pin-jack outlets for operating accessories (1 amp max)...a 3V, a 6V and a 9V. There is a built-in flashlight with a red filter that comes in handy during after-dark set-ups! Add to that an 800,000 candle-power halogen emergency spotlight built into the unit. It is certainly not for star parties, but if you leave the Power Tank in your car or someplace accessible in your home, the bright spotlight could be a lifesaver.
Re-chargeable? You bet. It comes with all the necessary gear to just plug it into any standard outlet to revive. One very cool feature is that it can also take a charge from your car, so if you forget at home, you can always charge while driving to a star party or to your remote location. For safety's sake, it will even add a power boost to a weak car battery, so it makes a great emergency tool. What's more, this product is Celestron durable. That means you're going to have it around and doing its job long after the warranty has expired.
Interested? You'll find the Celestron 12V 7AH Power Tank at OPT - and at a price you'll really like.
Friday, December 16, 2011
Weekly SkyWatcher's Forecast - December 16-22, 2011
Written by Tammy Plotner
Greetings, fellow SkyWatchers! It's going to be another great week. We have a host of unusual stars for you to explore - along with another meteor shower, a bit of history and even the upcoming solstice! Come on outside and join us... Because here's what's up!
Friday, December 16 - Tonight we’ll try our skills at observing an interesting variable star. RT (star 48) Aurigae is a bright Cepheid that is located roughly halfway between Epsilon Geminorum and Theta Aurigae. This perfect example of a pulsating star follows a precise timetable of 3.728 days and fluxes by close to one magnitude. Located 1600 light-years away, RT was first discovered in 1905 by T. H. Astbury of the British Astronomical Association. Like all Cepheids, it expands and contracts rhythmically - for reasons science is not completely sure of. Yet, we do know that it takes about 1.5 days for it to expand to its largest and brightest and 2.5 days for it to contract, cool, and dim.
Saturday, December 17 - Want a challenging double this evening? Then let's have a look at Theta Aurigae located on the east side of the pentagonal shape of this constellation. Located about 110 light-years away, 2.7 magnitude Theta is a four star system, whose members range in magnitude from 2.7 to 10.7. Suited even to a small telescope, the brightest member - Theta B - is itself a binary at magnitude 7.2, and was first recorded by Otto Struve in 1871. The pair moves quite slowly, and may take as long as 800 years to orbit each other at their separation of about 110 AU. The furthest member of this system was also noted by Struve as far back as 1852, but it is not a true member - the separation only occurring thanks to Theta's own proper motion. While you are there, be sure to note Theta's unusual color. While it will appear "white," look closely at the diffraction caused by our own atmosphere which acts much like a prism... You'll notice a lot more purple and blue around this star than many others of the same spectral type. Why? Theta is a silicon star!
Sunday, December 18 - Tonight let's head for Alpha Persei (Mirfak). While there's nothing particularly interesting about this 570 light-year distant star, what is incredible is the field in which it resides! Take a look at lowest power with a rich field telescope or binoculars and be prepared to be blown away... This is the Alpha Persei moving group - a fantastic field of main sequence stars that contains a little over 100 members. Even though it will take 90,000 years before any perceptible change is seen in this bright collection, they are happily moving at a pace of about 16 kilometers per second towards Beta Tauri! Enjoy this fine group also known as Melotte 20...
Monday, December 19 - Tonight is the peak of the Delta Arietid meteor shower. While most showers are best after midnight, this is an early evening shower that must be viewed before the radiant sets. The fall rate is modest - about 12 per hour. Today marks the founding of Mt. Wilson Solar Observatory. It officially opened its doors in 1904. We also celebrate the birth of Walter S. Adams on this date. Born in 1876, Adams was the astronomer at Mt. Wilson who revealed the nature of Sirius B, the first known white dwarf star. Sirius B was first seen by Alvan Clark in 1862 and most recently, the Hubble Space Telescope precisely measured the mass of B for the first time.
While Sirius is far too low at an early hour to study its white dwarf, we can have a look at a similar star when we view Omicron 2 Eridani located roughly a handspan west of Rigel. As the southernmost of the Omicron pair, it is sometimes known as 40 Eridani, and you'll find it to be an interesting multiple star system that's very worthy of your time. Discovered by William Herschel in 1783, this 16 light-year distant system is the eighth nearest of the unaided visible stars. Well spaced from the primary, the companion star is also a double for high powers and will reveal a red dwarf discovered by Otto Struve. Now, look closely at the 9th magnitude B star. This is the only white dwarf that can be considered "easy" for the backyard telescope. Its diameter is only about twice the size of Earth and its mass is about that of our Sun. Power up and locate the 11th magnitude companion - for it's one of the least massive stars known! And this white dwarf may be the smallest stellar object visible in an amateur telescope - it would be like spotting a tennis ball...on the Moon!
Tuesday, December 20 -While we're out tonight, let's have a look at one of the best known double stars in the night - Gamma Arietis (RA 01 53 31.81 Dec +19 17 37.9). Also known as Mesarthim, this combined magnitude 4 beauty was unintentionally discovered in 1664 by Robert Hooke who was following a comet. While no real change has been spotted in the more than 343 years since that time, there has been a slight difference detected in the components' radial velocities. Roughly 160 light-years away, you'll enjoy this almost matched-magnitude pair of white stars - but look carefully: in 1878, S. W. Burnham found a third star nearby that might not be a physical member, but is also a double!
Wednesday, December 21 - Up early? Fantastic! In the pre-dawn hours of this morning, I have a treat for you - the Ursid meteor shower! Cruising around the Sun about every thirteen and a half years, Comet 8P/Tuttle sheds a little skin. Although it never passes inside of Earth's orbit, some six years later we pass through its debris stream. Not so unusual? Then think again, because it takes as much as six centuries before the meteoroid trail is affected enough by Jupiter's gravitation to deflect the stream into our atmosphere. With little interference from the Moon while watching this circumpolar meteor shower, the hours before dawn could see activity of up to 12 per hour. By keeping watch on the constellation of Ursa Major, you just might spot one of these slow moving, 600 year old travelers that make their path only halfway between us and Selene!
Today marks Winter Solstice - for the northern hemisphere, the shortest day and the longest night of the year - and the point when the Sun is furthest south. Now is a wonderful time to demonstrate for yourself our own movements by choosing a "solstice marker." Anything from a fence post to a stick in the ground will suffice! Simply measure the shadow when the Sun reaches the zenith and repeat your experiment in the weeks ahead and watch as the shadow grows shorter...and the days grow longer!
Thursday, December 22 - Tonight we’ll look at a tremendous star as we head 150 light-years away to Menkar... Better known as Alpha Ceti, you'll find this nearly second magnitude giant orange beauty just west of Orion's "bow" (RA 03 02 16.77 Dec +04 05 23.0). With even a small telescope, you will also see 5th magnitude 93 Ceti in the eyepiece as well! Although they are not a true physical pair (the blue 93 is 350 light-years further away), they make a wonderful color contrast which is well worth your time. Just think... If 93 were as close as Menkar, it would be 250% brighter. But up the magnification and see if you can spot another true double in the field!
Until next week? May all your journeys be at light speed...
Greetings, fellow SkyWatchers! It's going to be another great week. We have a host of unusual stars for you to explore - along with another meteor shower, a bit of history and even the upcoming solstice! Come on outside and join us... Because here's what's up!
Friday, December 16 - Tonight we’ll try our skills at observing an interesting variable star. RT (star 48) Aurigae is a bright Cepheid that is located roughly halfway between Epsilon Geminorum and Theta Aurigae. This perfect example of a pulsating star follows a precise timetable of 3.728 days and fluxes by close to one magnitude. Located 1600 light-years away, RT was first discovered in 1905 by T. H. Astbury of the British Astronomical Association. Like all Cepheids, it expands and contracts rhythmically - for reasons science is not completely sure of. Yet, we do know that it takes about 1.5 days for it to expand to its largest and brightest and 2.5 days for it to contract, cool, and dim.
Saturday, December 17 - Want a challenging double this evening? Then let's have a look at Theta Aurigae located on the east side of the pentagonal shape of this constellation. Located about 110 light-years away, 2.7 magnitude Theta is a four star system, whose members range in magnitude from 2.7 to 10.7. Suited even to a small telescope, the brightest member - Theta B - is itself a binary at magnitude 7.2, and was first recorded by Otto Struve in 1871. The pair moves quite slowly, and may take as long as 800 years to orbit each other at their separation of about 110 AU. The furthest member of this system was also noted by Struve as far back as 1852, but it is not a true member - the separation only occurring thanks to Theta's own proper motion. While you are there, be sure to note Theta's unusual color. While it will appear "white," look closely at the diffraction caused by our own atmosphere which acts much like a prism... You'll notice a lot more purple and blue around this star than many others of the same spectral type. Why? Theta is a silicon star!
Sunday, December 18 - Tonight let's head for Alpha Persei (Mirfak). While there's nothing particularly interesting about this 570 light-year distant star, what is incredible is the field in which it resides! Take a look at lowest power with a rich field telescope or binoculars and be prepared to be blown away... This is the Alpha Persei moving group - a fantastic field of main sequence stars that contains a little over 100 members. Even though it will take 90,000 years before any perceptible change is seen in this bright collection, they are happily moving at a pace of about 16 kilometers per second towards Beta Tauri! Enjoy this fine group also known as Melotte 20...
Monday, December 19 - Tonight is the peak of the Delta Arietid meteor shower. While most showers are best after midnight, this is an early evening shower that must be viewed before the radiant sets. The fall rate is modest - about 12 per hour. Today marks the founding of Mt. Wilson Solar Observatory. It officially opened its doors in 1904. We also celebrate the birth of Walter S. Adams on this date. Born in 1876, Adams was the astronomer at Mt. Wilson who revealed the nature of Sirius B, the first known white dwarf star. Sirius B was first seen by Alvan Clark in 1862 and most recently, the Hubble Space Telescope precisely measured the mass of B for the first time.
While Sirius is far too low at an early hour to study its white dwarf, we can have a look at a similar star when we view Omicron 2 Eridani located roughly a handspan west of Rigel. As the southernmost of the Omicron pair, it is sometimes known as 40 Eridani, and you'll find it to be an interesting multiple star system that's very worthy of your time. Discovered by William Herschel in 1783, this 16 light-year distant system is the eighth nearest of the unaided visible stars. Well spaced from the primary, the companion star is also a double for high powers and will reveal a red dwarf discovered by Otto Struve. Now, look closely at the 9th magnitude B star. This is the only white dwarf that can be considered "easy" for the backyard telescope. Its diameter is only about twice the size of Earth and its mass is about that of our Sun. Power up and locate the 11th magnitude companion - for it's one of the least massive stars known! And this white dwarf may be the smallest stellar object visible in an amateur telescope - it would be like spotting a tennis ball...on the Moon!
Tuesday, December 20 -While we're out tonight, let's have a look at one of the best known double stars in the night - Gamma Arietis (RA 01 53 31.81 Dec +19 17 37.9). Also known as Mesarthim, this combined magnitude 4 beauty was unintentionally discovered in 1664 by Robert Hooke who was following a comet. While no real change has been spotted in the more than 343 years since that time, there has been a slight difference detected in the components' radial velocities. Roughly 160 light-years away, you'll enjoy this almost matched-magnitude pair of white stars - but look carefully: in 1878, S. W. Burnham found a third star nearby that might not be a physical member, but is also a double!
Wednesday, December 21 - Up early? Fantastic! In the pre-dawn hours of this morning, I have a treat for you - the Ursid meteor shower! Cruising around the Sun about every thirteen and a half years, Comet 8P/Tuttle sheds a little skin. Although it never passes inside of Earth's orbit, some six years later we pass through its debris stream. Not so unusual? Then think again, because it takes as much as six centuries before the meteoroid trail is affected enough by Jupiter's gravitation to deflect the stream into our atmosphere. With little interference from the Moon while watching this circumpolar meteor shower, the hours before dawn could see activity of up to 12 per hour. By keeping watch on the constellation of Ursa Major, you just might spot one of these slow moving, 600 year old travelers that make their path only halfway between us and Selene!
Today marks Winter Solstice - for the northern hemisphere, the shortest day and the longest night of the year - and the point when the Sun is furthest south. Now is a wonderful time to demonstrate for yourself our own movements by choosing a "solstice marker." Anything from a fence post to a stick in the ground will suffice! Simply measure the shadow when the Sun reaches the zenith and repeat your experiment in the weeks ahead and watch as the shadow grows shorter...and the days grow longer!
Thursday, December 22 - Tonight we’ll look at a tremendous star as we head 150 light-years away to Menkar... Better known as Alpha Ceti, you'll find this nearly second magnitude giant orange beauty just west of Orion's "bow" (RA 03 02 16.77 Dec +04 05 23.0). With even a small telescope, you will also see 5th magnitude 93 Ceti in the eyepiece as well! Although they are not a true physical pair (the blue 93 is 350 light-years further away), they make a wonderful color contrast which is well worth your time. Just think... If 93 were as close as Menkar, it would be 250% brighter. But up the magnification and see if you can spot another true double in the field!
Until next week? May all your journeys be at light speed...
Monday, December 12, 2011
Product Spotlight - The Celestron Green Laser Finderscope Kit
Written by Tammy Plotner
Now here's a product that's simple, easy-to-use and really adds to your relaxing observing nights. If you're like I am, you have a star chart imprinted in your head, but sometimes it's hard to aim your telescope at exactly where it needs to be. Sure, a red dot finder is nice, so are ones with an illuminated reticle. But there are times when I just can't get my head at the right angle to see through them - or the guide stars I need to use aren't bright enough to show up well. An optical finderscope has been my best companion over the years, but even with this time-honored method, I can run up against some problems - like too many stars in the field of view! Of course, I can always rely on setting circles or a computer program, but that's not what I want. What I want is to be able to point my telescope to a certain area in the sky - just like pointing my finger at exactly where I know something is at.
Enter the Celestron Green Laser Finderscope...
Just like using the green laser to point out certain stars, this clever device takes the place of your finderscope and delivers with point and shoot ease. When you take the time to line it up accurately, it will give you back amazingly accurate results. For example, if you know where M11 is located, just switch on the laser, put the beam on the mark and you're there. Not only does this aid you in pointing your telescope, but others around you can utilize your finding beam... from smaller telescopes using an optical finder, to someone using binoculars.
The Celestron Green Laser Finderscope is small, neat and clean. It's not any larger than your average supplied finderscope and close to the same weight. It comes with a supplied bracket that fits almost any standard dovetail mount and one for your SCT, too. What's more, it can be detached and handheld for those moments when you need it. And yes, the "Off/On" switch is a little stiff, but it's worth it as a safety precaution. The battery life is about the same as a red dot finder and it is bright enough to cut through most situations. All in all, it's a fine product at a modest investment - and one that will make your observing nights - and aiming your telescope - a lot more pleasant!
You can get a Celestron Green Laser Finderscope at OPT today!
Now here's a product that's simple, easy-to-use and really adds to your relaxing observing nights. If you're like I am, you have a star chart imprinted in your head, but sometimes it's hard to aim your telescope at exactly where it needs to be. Sure, a red dot finder is nice, so are ones with an illuminated reticle. But there are times when I just can't get my head at the right angle to see through them - or the guide stars I need to use aren't bright enough to show up well. An optical finderscope has been my best companion over the years, but even with this time-honored method, I can run up against some problems - like too many stars in the field of view! Of course, I can always rely on setting circles or a computer program, but that's not what I want. What I want is to be able to point my telescope to a certain area in the sky - just like pointing my finger at exactly where I know something is at.
Enter the Celestron Green Laser Finderscope...
Just like using the green laser to point out certain stars, this clever device takes the place of your finderscope and delivers with point and shoot ease. When you take the time to line it up accurately, it will give you back amazingly accurate results. For example, if you know where M11 is located, just switch on the laser, put the beam on the mark and you're there. Not only does this aid you in pointing your telescope, but others around you can utilize your finding beam... from smaller telescopes using an optical finder, to someone using binoculars.
The Celestron Green Laser Finderscope is small, neat and clean. It's not any larger than your average supplied finderscope and close to the same weight. It comes with a supplied bracket that fits almost any standard dovetail mount and one for your SCT, too. What's more, it can be detached and handheld for those moments when you need it. And yes, the "Off/On" switch is a little stiff, but it's worth it as a safety precaution. The battery life is about the same as a red dot finder and it is bright enough to cut through most situations. All in all, it's a fine product at a modest investment - and one that will make your observing nights - and aiming your telescope - a lot more pleasant!
You can get a Celestron Green Laser Finderscope at OPT today!
Friday, December 9, 2011
Weekly SkyWatcher's Forecast - December 9-15, 2011
Written by Tammy Plotner
Are you prepared for a great week of astronomy observations? Then you're going to enjoy meteors showers, a lunar eclipse, astronomy history, colorful stars and much, much more! When you're ready, let's head out to the backyard...
Friday, December 9 - If you are out stargazing, look for the peak of the Monocerid meteor shower. Its fall rate is around one per hour and its radiant point is near Gemini. While the bright Moon will interfere with this faint shower, you never know when you might catch a “shooter”!
Tonight is Full Moon and it has been given names such as the “Cold Moon” or “Long Nights Moon.” This is the time of winter cold and nights have become long and dark. In some cultures, this is also called the “Moon before Yule.” No matter what it’s called, early winter nights are indeed long and cold. Look for Luna moving high across the sky, opposite the now low Sun.
Saturday, December 10 - For Central and West Coast observers, don’t forget this is eclipse morning! Be sure to check our previous blog entry for more information!
On this date in 1863, Annie Jump Cannon was born. She was a United States astronomer who created the modern system for classifying stars by their spectra. Why not celebrate this achievement by coming along with me and viewing some very specific stars that have unusual visual spectral qualities! Let's grab a star chart, brush up on our Greek letters and start first with Mu Cephei.
Nicknamed the "Garnet Star," this is perhaps one of the reddest stars visible to the unaided eye. At around 1200 light-years away, this spectral type M2 star will show a delightful blue/purple "flash." If you still don't perceive color, try comparing Mu to its bright neighbor Alpha, a spectral type A7, or "white," star. Perhaps you'd like something a bit more off the beaten path? Then head for S Cephei about halfway between Kappa and Gamma toward the pole. Its intense shade of red makes this magnitude 10 star an incredibly worthwhile hunt.
To see an example of a B spectrum star, look no further than the Pleiades... All the components are blue white. Want to taste an "orange?" Then look again at Aldeberan, or Alpha Tauri, and say hello to a K spectrum star. Now that I have your curiosity aroused, would you like to see what our own Sun would look like? Then choose Alpha Aurigae, better known as Capella, and discover a spectral class G star that's only 160 times brighter than the one that holds our solar system together! If you're enjoying the game, then have a look at a star with one of the most unusual spectra of all - Theta Aurigae. Theta is actually a B class, or a blue/white, but instead of having strong lines in the helium, it has an abnormal concentration of silicon, making this incredibly unusual double star seem to glitter like a "black diamond."
Still no luck in seeing color? Don't worry. It does take a bit of practice! The cones in our eyes are the color receptors and when we go out in the dark, the color-blind rods take over. By intensifying the starlight with either a telescope or binoculars, we can usually excite the cones in our dark-adapted eyes to pick up on color.
Tonight is also the peak of the Sigma Hydrid meteor stream. Its radiant is near the head of the Serpent and the fall rate is also 12 per hour - but these are fast! I wish I could take away the Moon “shine” for you, but you just might spot one despite the light!
Sunday, December 11 - Today in 1961, OSCAR-1 was launched. The project started in 1960; the name stands for Orbital Satellite Carrying Amateur Radio. OSCAR-1 operated in orbit for 22 days, transmitting a signal in Morse Code - the simple greeting "Hi." The success of the mission helped to promote interest in amateur radio which still continues to this day!
Tonight before the Moon interferes with fainter studies, let's head far north for one of the oldest galactic clusters in our visible sky - NGC 188.
Hovering near Polaris (RA 00 44.5 Dec +85 20) this circumpolar open cluster also goes by other names: Collinder 1 and Melotte 2. Discovered by John Herschel on November 3, 1831, this 8th magnitude collection of faint stars will require a telescope to resolve its 120 members. At one time, it was believed to be as old as 24 billion years, later updated to 12 billion; but it is now considered to be around 5 billion years old. No matter how old it may truly be, it is one of the time-honored great studies and is also number one on the Caldwell list!
Monday, December 12 - Today in 1920, the first stellar diameter was measured by Francis Pease with an interferometer at Mt. Wilson. His target? Betelgeuse!
Tonight will being be one of the most hauntingly beautiful and most mysterious displays of celestial fireworks all year - the Geminid meteor shower. First noted in 1862 by Robert P. Greg in England, and B. V. Marsh and Prof. Alex C. Twining of the United States in independent studies, the annual appearance of the Geminid stream was weak initially, producing no more than a few per hour, but it has grown in intensity during the last century and a half. By 1877 astronomers realized a new annual shower was occurring with an hourly rate of about 14. At the turn of the century, it had increased to over 20, and by the 1930s up to 70 per hour. Only eight years ago observers recorded an outstanding 110 per hour during a moonless night... And, unfortunately, the Moon will soon interfere with observations. But no worries! We have a while yet to watch. Let’s talk…
So why are the Geminids such a mystery? Most meteor showers are historic - documented and recorded for hundred of years - and we know them as being cometary debris. When astronomers first began looking for the Geminids' parent comet, they found none. It wasn't until October 11, 1983 that Simon Green and John K. Davies, using data from NASA's Infrared Astronomical Satellite, detected an orbital object (confirmed the next night by Charles Kowal) that matched the Geminid meteoroid stream. But this was no comet, it was an asteroid.
Originally designated as 1983 TB, but later renamed 3200 Phaethon, this apparently rocky solar system member has a highly elliptical orbit that places it within 0.15 AU of the Sun about every year and half. But asteroids can't fragment like a comet - or can they? The original hypothesis was that since Phaethon's orbit passes through the asteroid belt, it may have collided with other asteroids creating rocky debris. This sounded good, but the more we studied the more we realized the meteoroid "path" occurred when Phaethon neared the Sun. So now our asteroid is behaving like a comet, yet it doesn't develop a tail.
So what exactly is this "thing?" Well, we do know that 3200 Phaethon orbits like a comet, yet has the spectral signature of an asteroid. By studying photographs of the meteor showers, scientists have determined that the meteors are denser than cometary material and not as dense as asteroid fragments. This leads us to believe that Phaethon is probably an extinct comet that has gathered a thick layer of interplanetary dust during its travels, yet retains the ice-like nucleus. Until we are able to take physical samples of this "mystery," we may never fully understand what Phaethon is, but we can fully appreciate the annual display it produces!
Thanks to the wide path of the stream, folks the world over get an opportunity to enjoy the show. The traditional peak time is tonight as soon as the constellation of Gemini appears around mid-evening. The radiant for the shower is right around bright star Castor, but meteors can originate from many points in the sky. From around 2 am tonight until dawn (when our local sky window is aimed directly into the stream) it's possible to see about one "shooting star" every 30 seconds. The most successful of observing nights are ones where you are comfortable, so be sure to use a reclining chair or pad the ground while looking up. Please get away from light sources when possible - it will triple the amount of meteors you see. Enjoy the incredible and mysterious Geminids!
Tuesday, December 13 - Today was a very busy day in astronomy history. Tycho Brahe was born in 1546. Brahe was a Danish pre-telescopic astronomer who established the first modern observatory in 1582 and gave Kepler his first job in the field. In 1962, Mariner 2 made a flyby of Venus and became the first successful interplanetary probe.
With some time before before Moonrise, let’s journey to a sparse portion of the Milky Way now high in the north just after skydark. Start by locating the two circumpolar constellations Cepheus and Cassiopeia and split the distance between Beta Cassiopeiae and Delta Cephei. Notice the stepping stones of 5th and 6th magnitude stars connecting them. Halfway between our two marker stars, go due south half a fist’s width. This brings us to a region of some 5 degrees in diameter devoid of stars brighter than magnitude 6.5. Sweep the area with binoculars or a telescope. Any suggestions as to why a 20 square degree area of the Milky Way would be so deficient in visible stars? Think obscure…
Wednesday, December 14 - Today in 1970, the Soviet spacecraft Venera 7 registered a first as it made a successful soft landing on Venus, and so went into the history books as the first craft to land on another planet.
Now let's travel 398 light-years away as we have a look at AR Aurigae - the centermost star in a brilliant collection. It is about one-third the distance from southern Beta to northern Alpha (Capella). AR is an eclipsing binary which consists of two main sequence white dwarf stars. About every 4.1 days, this pair will make a slight magnitude drop. While both are chemically peculiar, neither fills its Roche Lobe - meaning they are not stripping material from each other to cause these unusual abundances. Recent studies have shown the possibility of a third, unseen companion! But even binoculars will see that AR resides in a great field of stars and is worth a little of your time...
Thursday, December 15 - Today we celebrate the birthday of Edward Emerson (E. E.) Barnard. Born in 1857, Barnard was an American observational astronomer and an absolute legend. He led a very colorful life in astronomy, and his sharp skills have led to a multitude of discoveries. His life was a very fascinating one: Barnard was often known to simply set the scope on one point in the sky and just watch for new objects as the field moved! Tonight let's take a look at a bright star that has Barnard's touch, as we explore Beta Aurigae - Menkalinan.
First identified as a spectroscopic binary by A. Maury in 1890, Beta itself is part of a moving group of stars that includes Sirius, and is an Algol-type variable. While you won't see changes as dramatic as those of the "Demon Star," it has a precise drop of 0.09 magnitude every 3.96 days. This system contains almost identical stars which are more than two and a half times the size of our Sun, but they orbit each other at a distance of less than 0.1 AU! While Menkalinan's 10th magnitude optical companion was first spotted by Sir William Herschel in 1783, only E. E. Barnard noticed the 14th magnitude true tertiary to this incredible multiple system!
Until next week, ask for the Moon, but keep on reaching for the stars! ~Tammy
Are you prepared for a great week of astronomy observations? Then you're going to enjoy meteors showers, a lunar eclipse, astronomy history, colorful stars and much, much more! When you're ready, let's head out to the backyard...
Friday, December 9 - If you are out stargazing, look for the peak of the Monocerid meteor shower. Its fall rate is around one per hour and its radiant point is near Gemini. While the bright Moon will interfere with this faint shower, you never know when you might catch a “shooter”!
Tonight is Full Moon and it has been given names such as the “Cold Moon” or “Long Nights Moon.” This is the time of winter cold and nights have become long and dark. In some cultures, this is also called the “Moon before Yule.” No matter what it’s called, early winter nights are indeed long and cold. Look for Luna moving high across the sky, opposite the now low Sun.
Saturday, December 10 - For Central and West Coast observers, don’t forget this is eclipse morning! Be sure to check our previous blog entry for more information!
On this date in 1863, Annie Jump Cannon was born. She was a United States astronomer who created the modern system for classifying stars by their spectra. Why not celebrate this achievement by coming along with me and viewing some very specific stars that have unusual visual spectral qualities! Let's grab a star chart, brush up on our Greek letters and start first with Mu Cephei.
Nicknamed the "Garnet Star," this is perhaps one of the reddest stars visible to the unaided eye. At around 1200 light-years away, this spectral type M2 star will show a delightful blue/purple "flash." If you still don't perceive color, try comparing Mu to its bright neighbor Alpha, a spectral type A7, or "white," star. Perhaps you'd like something a bit more off the beaten path? Then head for S Cephei about halfway between Kappa and Gamma toward the pole. Its intense shade of red makes this magnitude 10 star an incredibly worthwhile hunt.
To see an example of a B spectrum star, look no further than the Pleiades... All the components are blue white. Want to taste an "orange?" Then look again at Aldeberan, or Alpha Tauri, and say hello to a K spectrum star. Now that I have your curiosity aroused, would you like to see what our own Sun would look like? Then choose Alpha Aurigae, better known as Capella, and discover a spectral class G star that's only 160 times brighter than the one that holds our solar system together! If you're enjoying the game, then have a look at a star with one of the most unusual spectra of all - Theta Aurigae. Theta is actually a B class, or a blue/white, but instead of having strong lines in the helium, it has an abnormal concentration of silicon, making this incredibly unusual double star seem to glitter like a "black diamond."
Still no luck in seeing color? Don't worry. It does take a bit of practice! The cones in our eyes are the color receptors and when we go out in the dark, the color-blind rods take over. By intensifying the starlight with either a telescope or binoculars, we can usually excite the cones in our dark-adapted eyes to pick up on color.
Tonight is also the peak of the Sigma Hydrid meteor stream. Its radiant is near the head of the Serpent and the fall rate is also 12 per hour - but these are fast! I wish I could take away the Moon “shine” for you, but you just might spot one despite the light!
Sunday, December 11 - Today in 1961, OSCAR-1 was launched. The project started in 1960; the name stands for Orbital Satellite Carrying Amateur Radio. OSCAR-1 operated in orbit for 22 days, transmitting a signal in Morse Code - the simple greeting "Hi." The success of the mission helped to promote interest in amateur radio which still continues to this day!
Tonight before the Moon interferes with fainter studies, let's head far north for one of the oldest galactic clusters in our visible sky - NGC 188.
Hovering near Polaris (RA 00 44.5 Dec +85 20) this circumpolar open cluster also goes by other names: Collinder 1 and Melotte 2. Discovered by John Herschel on November 3, 1831, this 8th magnitude collection of faint stars will require a telescope to resolve its 120 members. At one time, it was believed to be as old as 24 billion years, later updated to 12 billion; but it is now considered to be around 5 billion years old. No matter how old it may truly be, it is one of the time-honored great studies and is also number one on the Caldwell list!
Monday, December 12 - Today in 1920, the first stellar diameter was measured by Francis Pease with an interferometer at Mt. Wilson. His target? Betelgeuse!
Tonight will being be one of the most hauntingly beautiful and most mysterious displays of celestial fireworks all year - the Geminid meteor shower. First noted in 1862 by Robert P. Greg in England, and B. V. Marsh and Prof. Alex C. Twining of the United States in independent studies, the annual appearance of the Geminid stream was weak initially, producing no more than a few per hour, but it has grown in intensity during the last century and a half. By 1877 astronomers realized a new annual shower was occurring with an hourly rate of about 14. At the turn of the century, it had increased to over 20, and by the 1930s up to 70 per hour. Only eight years ago observers recorded an outstanding 110 per hour during a moonless night... And, unfortunately, the Moon will soon interfere with observations. But no worries! We have a while yet to watch. Let’s talk…
So why are the Geminids such a mystery? Most meteor showers are historic - documented and recorded for hundred of years - and we know them as being cometary debris. When astronomers first began looking for the Geminids' parent comet, they found none. It wasn't until October 11, 1983 that Simon Green and John K. Davies, using data from NASA's Infrared Astronomical Satellite, detected an orbital object (confirmed the next night by Charles Kowal) that matched the Geminid meteoroid stream. But this was no comet, it was an asteroid.
Originally designated as 1983 TB, but later renamed 3200 Phaethon, this apparently rocky solar system member has a highly elliptical orbit that places it within 0.15 AU of the Sun about every year and half. But asteroids can't fragment like a comet - or can they? The original hypothesis was that since Phaethon's orbit passes through the asteroid belt, it may have collided with other asteroids creating rocky debris. This sounded good, but the more we studied the more we realized the meteoroid "path" occurred when Phaethon neared the Sun. So now our asteroid is behaving like a comet, yet it doesn't develop a tail.
So what exactly is this "thing?" Well, we do know that 3200 Phaethon orbits like a comet, yet has the spectral signature of an asteroid. By studying photographs of the meteor showers, scientists have determined that the meteors are denser than cometary material and not as dense as asteroid fragments. This leads us to believe that Phaethon is probably an extinct comet that has gathered a thick layer of interplanetary dust during its travels, yet retains the ice-like nucleus. Until we are able to take physical samples of this "mystery," we may never fully understand what Phaethon is, but we can fully appreciate the annual display it produces!
Thanks to the wide path of the stream, folks the world over get an opportunity to enjoy the show. The traditional peak time is tonight as soon as the constellation of Gemini appears around mid-evening. The radiant for the shower is right around bright star Castor, but meteors can originate from many points in the sky. From around 2 am tonight until dawn (when our local sky window is aimed directly into the stream) it's possible to see about one "shooting star" every 30 seconds. The most successful of observing nights are ones where you are comfortable, so be sure to use a reclining chair or pad the ground while looking up. Please get away from light sources when possible - it will triple the amount of meteors you see. Enjoy the incredible and mysterious Geminids!
Tuesday, December 13 - Today was a very busy day in astronomy history. Tycho Brahe was born in 1546. Brahe was a Danish pre-telescopic astronomer who established the first modern observatory in 1582 and gave Kepler his first job in the field. In 1962, Mariner 2 made a flyby of Venus and became the first successful interplanetary probe.
With some time before before Moonrise, let’s journey to a sparse portion of the Milky Way now high in the north just after skydark. Start by locating the two circumpolar constellations Cepheus and Cassiopeia and split the distance between Beta Cassiopeiae and Delta Cephei. Notice the stepping stones of 5th and 6th magnitude stars connecting them. Halfway between our two marker stars, go due south half a fist’s width. This brings us to a region of some 5 degrees in diameter devoid of stars brighter than magnitude 6.5. Sweep the area with binoculars or a telescope. Any suggestions as to why a 20 square degree area of the Milky Way would be so deficient in visible stars? Think obscure…
Wednesday, December 14 - Today in 1970, the Soviet spacecraft Venera 7 registered a first as it made a successful soft landing on Venus, and so went into the history books as the first craft to land on another planet.
Now let's travel 398 light-years away as we have a look at AR Aurigae - the centermost star in a brilliant collection. It is about one-third the distance from southern Beta to northern Alpha (Capella). AR is an eclipsing binary which consists of two main sequence white dwarf stars. About every 4.1 days, this pair will make a slight magnitude drop. While both are chemically peculiar, neither fills its Roche Lobe - meaning they are not stripping material from each other to cause these unusual abundances. Recent studies have shown the possibility of a third, unseen companion! But even binoculars will see that AR resides in a great field of stars and is worth a little of your time...
Thursday, December 15 - Today we celebrate the birthday of Edward Emerson (E. E.) Barnard. Born in 1857, Barnard was an American observational astronomer and an absolute legend. He led a very colorful life in astronomy, and his sharp skills have led to a multitude of discoveries. His life was a very fascinating one: Barnard was often known to simply set the scope on one point in the sky and just watch for new objects as the field moved! Tonight let's take a look at a bright star that has Barnard's touch, as we explore Beta Aurigae - Menkalinan.
First identified as a spectroscopic binary by A. Maury in 1890, Beta itself is part of a moving group of stars that includes Sirius, and is an Algol-type variable. While you won't see changes as dramatic as those of the "Demon Star," it has a precise drop of 0.09 magnitude every 3.96 days. This system contains almost identical stars which are more than two and a half times the size of our Sun, but they orbit each other at a distance of less than 0.1 AU! While Menkalinan's 10th magnitude optical companion was first spotted by Sir William Herschel in 1783, only E. E. Barnard noticed the 14th magnitude true tertiary to this incredible multiple system!
Until next week, ask for the Moon, but keep on reaching for the stars! ~Tammy
Thursday, December 8, 2011
Total Lunar Eclipse - Saturday, December 10, 2011
Written by Tammy Plotner
Are you ready for some good, old-fashioned observing fun? Although you might not want to get up early, it's going to be worth your time. This Saturday, December 10, 2011, marks the last total lunar eclipse event for the western portion of the Americas until 2014. While a solar eclipse event has a very small footprint where it is visible, a lunar eclipse has a wide and wonderful path that encompasses a huge amount of viewers. “We’re all looking at this together,” says Sky & Telescope senior editor Alan MacRobert.
If you live in the eastern portion of the Americas, sorry... You'll miss out on this one. In the Central time zone, the Moon will be setting while it is partially eclipsed. However, beginning in a line that takes in Arizona and the Dakotas you'll be treated to the beginning of the lunar eclipse, totality, and it will set as it is beginning to come out of eclipse. If you live in the western portion of the US or Canada? Lucky you! You'll get to enjoy the Moon as it goes through the initial states of eclipse, see totality and even might catch the phases as it slips out of Earth's shadow again - just as the Sun begins to rise. For Skywatchers in Hawaii, Australia, and East Asia, you'll have it better. Seen from there, the whole eclipse happens high in a dark sky from start to finish. For Europe and Africa, the eclipsed Moon will be lower in the east during or after twilight on the evening of the 10th.
When exactly does the event begin? The lunar eclipse will be total from 6:05 to 6:57 a.m. Pacific Standard Time. The partial stage of the eclipse begins more than an hour earlier, at 4:45 a.m. PST. Be sure to watch the southern lunar edge, too. Because the Moon will be skimming by the southern edge of the Earth's shadow, it will remain slightly brighter and add to the dimensional effect you'll see. Enjoy the coppery colors from the refracted sunlight! The Moon won't be black - but it will most certainly be a very photogenic experience.
“That red light on the Moon during a lunar eclipse comes from all the sunrises and sunsets around the Earth at the time,” explains Sky & Telescope editor in chief Robert Naeye. “If you were an astronaut standing on the Moon and looking up, the whole picture would be clear. The Sun would be covered up by a dark Earth that was ringed all around with a thin, brilliant band of sunset- and sunrise-colored light -- bright enough to dimly illuminate the lunar landscape around you.”
May clear skies be yours!
Original News Source: Sky and Telescope News Release. Image Credits: Sky and Telescope. Be sure to visit Universe Today for the best in space news!
Are you ready for some good, old-fashioned observing fun? Although you might not want to get up early, it's going to be worth your time. This Saturday, December 10, 2011, marks the last total lunar eclipse event for the western portion of the Americas until 2014. While a solar eclipse event has a very small footprint where it is visible, a lunar eclipse has a wide and wonderful path that encompasses a huge amount of viewers. “We’re all looking at this together,” says Sky & Telescope senior editor Alan MacRobert.
If you live in the eastern portion of the Americas, sorry... You'll miss out on this one. In the Central time zone, the Moon will be setting while it is partially eclipsed. However, beginning in a line that takes in Arizona and the Dakotas you'll be treated to the beginning of the lunar eclipse, totality, and it will set as it is beginning to come out of eclipse. If you live in the western portion of the US or Canada? Lucky you! You'll get to enjoy the Moon as it goes through the initial states of eclipse, see totality and even might catch the phases as it slips out of Earth's shadow again - just as the Sun begins to rise. For Skywatchers in Hawaii, Australia, and East Asia, you'll have it better. Seen from there, the whole eclipse happens high in a dark sky from start to finish. For Europe and Africa, the eclipsed Moon will be lower in the east during or after twilight on the evening of the 10th.When exactly does the event begin? The lunar eclipse will be total from 6:05 to 6:57 a.m. Pacific Standard Time. The partial stage of the eclipse begins more than an hour earlier, at 4:45 a.m. PST. Be sure to watch the southern lunar edge, too. Because the Moon will be skimming by the southern edge of the Earth's shadow, it will remain slightly brighter and add to the dimensional effect you'll see. Enjoy the coppery colors from the refracted sunlight! The Moon won't be black - but it will most certainly be a very photogenic experience.
“That red light on the Moon during a lunar eclipse comes from all the sunrises and sunsets around the Earth at the time,” explains Sky & Telescope editor in chief Robert Naeye. “If you were an astronaut standing on the Moon and looking up, the whole picture would be clear. The Sun would be covered up by a dark Earth that was ringed all around with a thin, brilliant band of sunset- and sunrise-colored light -- bright enough to dimly illuminate the lunar landscape around you.”
May clear skies be yours!
Original News Source: Sky and Telescope News Release. Image Credits: Sky and Telescope. Be sure to visit Universe Today for the best in space news!
Wednesday, December 7, 2011
Staking Out Vampire Stars
Written by Tammy Plotner
How do you peer into the dark heart of a vampire star? Try combining four telescopes! At ESO’s Paranal Observatory they created a virtual telescope 130 metres across with vision 50 times sharper than the NASA/ESA Hubble Space Telescope and observed a very unusual event... the transfer of mass from one star to another. While you might assume this to be a violent action, it turns out that it's a gradual drain. Apparently SS Leporis stands for "super slow".
“We can now combine light from four VLT telescopes and create super-sharp images much more quickly than before,” says Nicolas Blind (IPAG, Grenoble, France), who is the lead author on the paper presenting the results, “The images are so sharp that we can not only watch the stars orbiting around each other, but also measure the size of the larger of the two stars.”
This stellar duo, cataloged as SS Leporis, are only separated by slightly more than one AU and have an orbital period of 260 days. Of the two, the more massive and cooler member expands to a size of about Mercury's orbit. It's this very action of being pushed closer that draws the hot companion to feed on its host - consuming almost half of its mass. Weird? You bet.
“We knew that this double star was unusual, and that material was flowing from one star to the other,” says co-author Henri Boffin, from ESO. “What we found, however, is that the way in which the mass transfer most likely took place is completely different from previous models of the process. The ‘bite’ of the vampire star is very gentle but highly effective.”
The technique of combining telescopes gives us an incredibly candid image - one which shows us the larger star isn't quite as large as surmised. Rather than clarifying the picture, it complicates. Just how did a red giant lose matter to its companion? Researchers are guessing rather than streaming material from one star to another, that stellar winds may have released mass - only to be collected by the companion vampire star.
“These observations have demonstrated the new snapshot imaging capability of the Very Large Telescope Interferometer. They pave the way for many further fascinating studies of interacting double stars,” concludes co-author Jean-Philippe Berger.
Where's van Helsing when you need him?
Original Story Source: ESO Press Release For Further Reading: An Incisive Look At The Symbiotic Star SS Leoporis. Image Credit: Credit: ESO/PIONIER/IPAG
How do you peer into the dark heart of a vampire star? Try combining four telescopes! At ESO’s Paranal Observatory they created a virtual telescope 130 metres across with vision 50 times sharper than the NASA/ESA Hubble Space Telescope and observed a very unusual event... the transfer of mass from one star to another. While you might assume this to be a violent action, it turns out that it's a gradual drain. Apparently SS Leporis stands for "super slow".
“We can now combine light from four VLT telescopes and create super-sharp images much more quickly than before,” says Nicolas Blind (IPAG, Grenoble, France), who is the lead author on the paper presenting the results, “The images are so sharp that we can not only watch the stars orbiting around each other, but also measure the size of the larger of the two stars.”
This stellar duo, cataloged as SS Leporis, are only separated by slightly more than one AU and have an orbital period of 260 days. Of the two, the more massive and cooler member expands to a size of about Mercury's orbit. It's this very action of being pushed closer that draws the hot companion to feed on its host - consuming almost half of its mass. Weird? You bet.
“We knew that this double star was unusual, and that material was flowing from one star to the other,” says co-author Henri Boffin, from ESO. “What we found, however, is that the way in which the mass transfer most likely took place is completely different from previous models of the process. The ‘bite’ of the vampire star is very gentle but highly effective.”
The technique of combining telescopes gives us an incredibly candid image - one which shows us the larger star isn't quite as large as surmised. Rather than clarifying the picture, it complicates. Just how did a red giant lose matter to its companion? Researchers are guessing rather than streaming material from one star to another, that stellar winds may have released mass - only to be collected by the companion vampire star.
“These observations have demonstrated the new snapshot imaging capability of the Very Large Telescope Interferometer. They pave the way for many further fascinating studies of interacting double stars,” concludes co-author Jean-Philippe Berger.
Where's van Helsing when you need him?
Original Story Source: ESO Press Release For Further Reading: An Incisive Look At The Symbiotic Star SS Leoporis. Image Credit: Credit: ESO/PIONIER/IPAG
Monday, December 5, 2011
Product Spotlight - Celestron Digital Weather Stations
Written by Tammy Plotner
Interested in the weather? Want to monitor observing conditions in your location? Do you like fun, science-oriented equipment? Then you need to check out the Celestron Digital Weather Stations for your home, office, cabin, observatory, or other location. These handy - and affordable - gadgets come loaded with features which are not only useful, but educational as well. Curious? Then read on...
For those who make astronomical observations, we know there's a lot of information that needs to be included in a report and how many times have you wished you could get it all in one easy place? Now you can with the Celestron Compact Weather Station....
This ingenious little device measures only 3.1" x 1.8" x 5.6" (79mm x 46mm x 142mm) and weighs just 5 ounces. One look at the display screen of the Celestron Compact Weather Station and you'll instantly know the moon phase, time, date, temperature displays indoor and outdoor in either F or C, humidity both indoors and out and cloud cover. Other features include a weather forecast, digital quartz alarm clock with snooze, alert for minimum and maximum indoor temperature... and even a calendar that displays month, day, day of week!
For astrophotographers and astronomers, there's nothing more important than having all your weather information and so much more handy before a night's observing. Why clutter up your work space with several gadgets when you can have them all in one neat, compact unit? Check out all the features of the Celestron Compact Barometric Weather Station! The Celestron Compact Barometric Weather Station offers up a temperature sensor that displays indoor and outdoor in either F or C, a built-in hygrometer that gives you a readout of indoor humidity, and built-in barometer which provides indication of current weather and atmospheric pressure. But that's not all...
Time is important and the built-in quartz clock provides accuracy along with an alarm and snooze feature. The internal calendar displays month, day, day of week - along with moon phase and tide information. There's even an alert feature for minimum and maximum for indoor and outdoor temperature!
The Celestron Deluxe Weather Station simply rocks. In just this little unit you'll get all the information you need, such as indoor and outdoor temperature and humidity, weather forecast, wind chill, speed, gust and direction, ice alert, dewpoint, heat index and more. It even provides rainfall and rainfall history! The built-in hygrometer provides you with accurate information on humidity both indoors and out, while the internal barometer on the Celestron Deluxe Weather Station gives a weather forecast indication of current weather along with atmospheric pressure display. You'll even know the Heat Index - the combined effects of temperature and humidity - as well as the Dew Point - the saturation of the air to get condensation. But the features don't stop there... When the wind blows, you'll know Wind Speed and Direction - information received from supplied Anemometer... Wind Gust - average gusts and alarm function... and even Wind Chill - combination of temperature and wind speed and has alarm function. The digital quartz clock will provide accurate time and even has alarm and snooze functions for those long nights!
The Celestron 4 Color LCD Weather Station is more than information... It's an eye-catching work of art! The 4-color LCD displays information like temperatures and humidity both indoors and out in bright, vibrant colors. You'll enjoy a Weather Forecast indication of current weather with built-in barometer, as well as a Heat Index (the combined effects of temperature and humidity and Dew Point (measures saturation of the air to get condensation). But that's not all.... The Celestron 4 Color LCD Weather Station also has a built-in digital quartz, snooze-equipped alarm clock for accurate time and a calendar which displays month, day, day of week. What's more, the Celestron Color Weather Station tells you the moon phase, too! The Celestron 4 Color LCD Weather Station is not only pretty to look at, but compact as well - measuring only 2.8" x 2.5" x 8.4" (71mm x 64mm x 213mm) and weighing in at 10 ounces. There's even an AC Adapter included! What are you waiting for? It would look great in your observatory!
The very best part about all of the Celestron Digital Weather Stations is Celestron quality and affordability. We're not talking about a cheap toy here... These are rugged little pieces of scientific equipment that are meant to "weather" the conditions they need to perform under - and do it inexpensively. The Celestron Digital Weather Stations have a starting point of $20 ranging through $90. Not only are these weather stations a very cool conversation piece, but the functionality for an observatory puts them at the head of the class. You won't be disappointed in the investment.
Interested in the weather? Want to monitor observing conditions in your location? Do you like fun, science-oriented equipment? Then you need to check out the Celestron Digital Weather Stations for your home, office, cabin, observatory, or other location. These handy - and affordable - gadgets come loaded with features which are not only useful, but educational as well. Curious? Then read on...
For those who make astronomical observations, we know there's a lot of information that needs to be included in a report and how many times have you wished you could get it all in one easy place? Now you can with the Celestron Compact Weather Station....
This ingenious little device measures only 3.1" x 1.8" x 5.6" (79mm x 46mm x 142mm) and weighs just 5 ounces. One look at the display screen of the Celestron Compact Weather Station and you'll instantly know the moon phase, time, date, temperature displays indoor and outdoor in either F or C, humidity both indoors and out and cloud cover. Other features include a weather forecast, digital quartz alarm clock with snooze, alert for minimum and maximum indoor temperature... and even a calendar that displays month, day, day of week!
For astrophotographers and astronomers, there's nothing more important than having all your weather information and so much more handy before a night's observing. Why clutter up your work space with several gadgets when you can have them all in one neat, compact unit? Check out all the features of the Celestron Compact Barometric Weather Station! The Celestron Compact Barometric Weather Station offers up a temperature sensor that displays indoor and outdoor in either F or C, a built-in hygrometer that gives you a readout of indoor humidity, and built-in barometer which provides indication of current weather and atmospheric pressure. But that's not all...
Time is important and the built-in quartz clock provides accuracy along with an alarm and snooze feature. The internal calendar displays month, day, day of week - along with moon phase and tide information. There's even an alert feature for minimum and maximum for indoor and outdoor temperature!
The Celestron Deluxe Weather Station simply rocks. In just this little unit you'll get all the information you need, such as indoor and outdoor temperature and humidity, weather forecast, wind chill, speed, gust and direction, ice alert, dewpoint, heat index and more. It even provides rainfall and rainfall history! The built-in hygrometer provides you with accurate information on humidity both indoors and out, while the internal barometer on the Celestron Deluxe Weather Station gives a weather forecast indication of current weather along with atmospheric pressure display. You'll even know the Heat Index - the combined effects of temperature and humidity - as well as the Dew Point - the saturation of the air to get condensation. But the features don't stop there... When the wind blows, you'll know Wind Speed and Direction - information received from supplied Anemometer... Wind Gust - average gusts and alarm function... and even Wind Chill - combination of temperature and wind speed and has alarm function. The digital quartz clock will provide accurate time and even has alarm and snooze functions for those long nights!The Celestron 4 Color LCD Weather Station is more than information... It's an eye-catching work of art! The 4-color LCD displays information like temperatures and humidity both indoors and out in bright, vibrant colors. You'll enjoy a Weather Forecast indication of current weather with built-in barometer, as well as a Heat Index (the combined effects of temperature and humidity and Dew Point (measures saturation of the air to get condensation). But that's not all.... The Celestron 4 Color LCD Weather Station also has a built-in digital quartz, snooze-equipped alarm clock for accurate time and a calendar which displays month, day, day of week. What's more, the Celestron Color Weather Station tells you the moon phase, too! The Celestron 4 Color LCD Weather Station is not only pretty to look at, but compact as well - measuring only 2.8" x 2.5" x 8.4" (71mm x 64mm x 213mm) and weighing in at 10 ounces. There's even an AC Adapter included! What are you waiting for? It would look great in your observatory!The very best part about all of the Celestron Digital Weather Stations is Celestron quality and affordability. We're not talking about a cheap toy here... These are rugged little pieces of scientific equipment that are meant to "weather" the conditions they need to perform under - and do it inexpensively. The Celestron Digital Weather Stations have a starting point of $20 ranging through $90. Not only are these weather stations a very cool conversation piece, but the functionality for an observatory puts them at the head of the class. You won't be disappointed in the investment.
Friday, December 2, 2011
Weekly SkyWatcher's Forecast - December 3-9, 2011
Written by Tammy Plotner
Friday, December 3 - Today in 1971, the Soviet Mars 3 became the first spacecraft to make a soft landing on the red planet, and two years later on this same date the Pioneer 10 mission became the first spacecraft to fly by Jupiter. One year later on this same date? Pioneer 11 did the same thing!
Tonight is a wonderful chance for binoculars and small telescopes to study the Moon. Craters Aristotle and Eudoxus to the north will be easily apparent, along with the Caucasus and Apennine mountain range. Are you looking for a slight telescopic lunar challenge? Then look no further than the Valles Alpes. More commonly known as the “Alpine Valley” this deep gash cut across the northern surface will be easily visible and the lighting conditions will be just right to explore its 1.6 km to 20.9 km (1-13 mile) wide and 177 km (110 mile) long expanse.
Now let's familiarize ourselves with the vague constellation of Fornax. Its three brightest stars form a shallow V just south of the Cetus/Eridanus border and span less than a handwidth of sky. Although it's on the low side for northern observers, there is a wealth of sky objects in this area.
Try having a look at the easternmost star - 40-light-year distant Alpha. At magnitude 4, it is not easy, but what you'll find there is quite beautiful. For binoculars, you'll see a delightful cluster of stars around this long-term binary - but telescopes will enjoy it as a great golden double star! First measured by John Herschel in 1835, the distance between the pair has narrowed and widened over the last 172 years and it is suspected its orbital period may be 314 years. While the 7th magnitude secondary can be spotted with a small scope - watch out - because it may also be a variable which drops by as much as a full magnitude!
Saturday, December 4 - Today in 1978, the Pioneer/Venus Orbiter became the first spacecraft to orbit Venus. And in 1996, the Mars Pathfinder mission was launched!
Tonight one of the most sought-after and unusual features will be visible to small telescopes in the southern half of the Moon near the terminator – Rupes Recta! Also known as “The Straight Wall”, this 130 km (75 mile) long, 366 meter (1200 ft.) high feature slopes upward with the steepest angle on the lunar surface at 41 degrees. It will be a challenge under these lighting conditions, but look for triple ring craters Ptolemy, Alphonsus and Arzachel to guide you. The “Straight Wall” will appear as a very thin line stretching across the edge of Mare Nubium.
A star for all seasons is Polaris. Take the opportunity to see what magnification gives the best view of its 8.9 magnitude companion. This one can be tough for small scopes during Full Moon, so try for the right magnification to balance things like sky contrast and image scale. This teaches lots of lessons that really make a difference in resolving even more desperate disparates!
Sunday, December 5 - Let’s begin this evening with some lunar exploration as crater Copernicus becomes visible to even the most modest of optical aids. Small binoculars will see Copernicus as a bright “ring” about midway along the lunar dividing line of light and dark called the “terminator”. Telescopes will reveal its 97 km (60 mile) expanse and 120 meter (1200 ft.) central peak to perfection. Copernicus holds special appeal as it’s the aftermath of a huge meteoric impact! At 3800 meters (12,600 feet) deep, its walls are around 22 km (14 miles) thick and over the next few days, the impact ray system extending from this tremendous crater will become wonderfully apparent.
Now let’s have a look at a splendid set of colors – 1 Arietis. Because this pair is faint, you will need to apply “stellar geometry” to track it down. To find it, start with Alpha and Beta and form a right triangle whose third point is less than a finger-width northwest of Beta. Center the scope at moderate powers on that locale, then use the finder to pick out the nearest 6th magnitude star – 1 Arietis. Look for a 7.8 magnitude green companion south-southeast of the 5.8 magnitude white primary.
Monday, December 6 - It’s a “Moon Gazer’s” night as our nearest astronomical neighbor continues to light up the night sky. Even from 383,000 km (238,000 miles) away! Don’t put away your telescopes and binoculars thinking there will be nothing to view, because one of the most “romantic” features on the lunar surface will be highlighted tonight.
The Sinus Iridium is one of the most fascinating and calming areas on the Moon. At around 241 km (150 miles) in diameter and ringed by the Juras Mountains, it’s known as the quiet name of “The Bay of Rainbows” but was formed by a cataclysm. Science speculates that a minor planet around 201 km (125 miles) in diameter once impacted our forming Moon with a glancing strike and the result of that impact caused “waves” of material to wash up to a “shoreline” forming this delightful C-shaped lunar feature. The effect of looking at a bay is stunning as the smooth inner sands show soft waves called “rilles”, broken only by a few small, impact craters. The picture is complete as Promentoriums Heraclides and LaPlace tower above the surface at 1800 meters (5900 ft.) and 3000 meters (9900 feet) respectively and appear as distant “lighthouses” set on either tip of Sinus Iridum’s opening.
For northern observers clamoring for brighter stellar action, look no further tonight than the incredible "Double Cluster" about four fingerwidths southeast of Delta Cassiopeiae. At a dark sky site, this incredible pair is easily located visually and stunning in any size binoculars and telescopes.
As part of the constellation of Perseus, this double delight is around 7000 light-years away and less than 100 light-years separates the pair. While open clusters in this area are not really a rarity, what makes the "Double Cluster" so inviting is the large amount of bright stars within each of them. Well known since the very beginnings of astronomy, take the time to have a close look at both Chi (NGC 884) and H Persei very carefully. Note how many colorful stars you see, and the vast array of double, multiple and variable systems!
Tuesday, December 7 - Today is the birthday of Gerard Kuiper. Born 1905, Kuiper was a Dutch-born American planetary scientist who discovered moons of both Uranus and Neptune. He was the first to know that Titan had an atmosphere, and he studied the origins of comets and the solar system.
Take the time tonight to once again return to the Moon and explore with binoculars or telescopes the area to the south around another easy and delightful lunar feature, the crater Gassendi. At around 110 km (70 miles) in diameter and 2010 meters (6600 feet) deep, this ancient crater contains a triple mountain peak in its center. As one of the most “perfect circles” on the Moon, the south wall of Gassendi has been eroded by lava flows over a 48 km (30 mile) expanse and offers a great amount of details to telescopic observers on its ridge and rille covered floor. For those observing with binoculars? Gassendi’s bright ring stands on the north shore of Mare Humorum… An area about the size of the state of Arkansas!
Wednesday, December 8 - Today in history (1908) marks "first light" for the 60" Hale Telescope at Mt. Wilson Observatory. Not only was it the largest telescope of the time, but it ended up being one of the most productive of all. Almost 100 years later, the 60" Hale is still in service as a public outreach instrument.
The waxing Moon will dominate the early evening skies, but tonight is an excellent opportunity for binoculars and telescopes to explore crater Tycho. Named for Danish astronomer, Tycho Brahe, this fantastic impact crater will be very impressive in even the most modest of optical aids. Spanning 85 km (56 miles), this lunar feature is very prominent and unmistakable in the southern hemisphere of the Moon. Tycho’s highly conspicuous ray systems support its impact crater theory and span hundreds of kilometers across the lunar surface. Tycho is also one of the youngest of the major features at an astounding age of only 50 million years old!
On January 9, 1968 Surveyor 7 (the last lunar robot of its kind) landed quietly on Tycho’s slopes at sunrise. Because previous Surveyor missions had provided the Apollo program with all the data necessary to their goals, Surveyor 7′s presence was scientific only. Two weeks later, when the Sun set on the landing site, Surveyor 7 had provided over 21,000 photographs, determined physical and chemical properties associated with the Southern Highland area and recorded the laser beams aimed toward it from two separate Earth observatories.
Thursday, December 9 - Southern Hemisphere viewers, you're in luck for a meteor shower. This is the maximum of the Puppid-Velid meteor shower. With an average fall rate of about 10 per hour, this particular meteor shower could also be visible to those far enough south to see the constellation of Puppis. Very little is known about this shower except that the streams and radiants are very tightly bound together. Since studies of the Puppid-Velids are just beginning, why not take the opportunity to watch? Viewing will be possible all night long and although most of the meteors are faint, this one is known to produce an occasional fireball.
Tonight the very gibbous Moon will command the skies and give unaided observers an opportunity to use their imaginations. Since the dawn of mankind, we have been gazing at the Moon and seeing fanciful shapes in the lunar features. Tonight as the Moon rises is your chance to catch “The Rabbit In The Moon”. The “Rabbit” is a compilation of all the dark maria. The Oceanus Procellarum forms the “ear” while the Mare Humorum makes the “nose”. The “body” is Mare Ibrium and the “front legs” appear to be Mare Nubium. Mare Serentatis is the “backside” and the picture is complete where Mare Tranquilitatus and Mare Fecunditatis shape the “hind legs” with Crisium as the “tail”.
See the Moon with an open mind and open eyes — and find the “Rabbit”!
For telescopes and binoculars, the lunar surface will provide a bright but superior view of crater Grimaldi. Named for Italian physicist and astronomer, Francesco Grimaldi, this deep grey oval is one of the darkest albedo features on the Moon – only reflecting about 6% of the light. Approximately 430 km (140-145 miles) long, it’s easy to spot along the terminator and just slightly south of the center of the lunar limb. Tonight is the best time to view its mountained walls, for they will disappear and Grimaldi will take on the appearance of a small mare in the light of the full Moon.
Until next week, may all your journeys be at light speed! ~Tammy
Friday, December 3 - Today in 1971, the Soviet Mars 3 became the first spacecraft to make a soft landing on the red planet, and two years later on this same date the Pioneer 10 mission became the first spacecraft to fly by Jupiter. One year later on this same date? Pioneer 11 did the same thing!
Tonight is a wonderful chance for binoculars and small telescopes to study the Moon. Craters Aristotle and Eudoxus to the north will be easily apparent, along with the Caucasus and Apennine mountain range. Are you looking for a slight telescopic lunar challenge? Then look no further than the Valles Alpes. More commonly known as the “Alpine Valley” this deep gash cut across the northern surface will be easily visible and the lighting conditions will be just right to explore its 1.6 km to 20.9 km (1-13 mile) wide and 177 km (110 mile) long expanse.
Now let's familiarize ourselves with the vague constellation of Fornax. Its three brightest stars form a shallow V just south of the Cetus/Eridanus border and span less than a handwidth of sky. Although it's on the low side for northern observers, there is a wealth of sky objects in this area.
Try having a look at the easternmost star - 40-light-year distant Alpha. At magnitude 4, it is not easy, but what you'll find there is quite beautiful. For binoculars, you'll see a delightful cluster of stars around this long-term binary - but telescopes will enjoy it as a great golden double star! First measured by John Herschel in 1835, the distance between the pair has narrowed and widened over the last 172 years and it is suspected its orbital period may be 314 years. While the 7th magnitude secondary can be spotted with a small scope - watch out - because it may also be a variable which drops by as much as a full magnitude!
Saturday, December 4 - Today in 1978, the Pioneer/Venus Orbiter became the first spacecraft to orbit Venus. And in 1996, the Mars Pathfinder mission was launched!
Tonight one of the most sought-after and unusual features will be visible to small telescopes in the southern half of the Moon near the terminator – Rupes Recta! Also known as “The Straight Wall”, this 130 km (75 mile) long, 366 meter (1200 ft.) high feature slopes upward with the steepest angle on the lunar surface at 41 degrees. It will be a challenge under these lighting conditions, but look for triple ring craters Ptolemy, Alphonsus and Arzachel to guide you. The “Straight Wall” will appear as a very thin line stretching across the edge of Mare Nubium.
A star for all seasons is Polaris. Take the opportunity to see what magnification gives the best view of its 8.9 magnitude companion. This one can be tough for small scopes during Full Moon, so try for the right magnification to balance things like sky contrast and image scale. This teaches lots of lessons that really make a difference in resolving even more desperate disparates!
Sunday, December 5 - Let’s begin this evening with some lunar exploration as crater Copernicus becomes visible to even the most modest of optical aids. Small binoculars will see Copernicus as a bright “ring” about midway along the lunar dividing line of light and dark called the “terminator”. Telescopes will reveal its 97 km (60 mile) expanse and 120 meter (1200 ft.) central peak to perfection. Copernicus holds special appeal as it’s the aftermath of a huge meteoric impact! At 3800 meters (12,600 feet) deep, its walls are around 22 km (14 miles) thick and over the next few days, the impact ray system extending from this tremendous crater will become wonderfully apparent.
Now let’s have a look at a splendid set of colors – 1 Arietis. Because this pair is faint, you will need to apply “stellar geometry” to track it down. To find it, start with Alpha and Beta and form a right triangle whose third point is less than a finger-width northwest of Beta. Center the scope at moderate powers on that locale, then use the finder to pick out the nearest 6th magnitude star – 1 Arietis. Look for a 7.8 magnitude green companion south-southeast of the 5.8 magnitude white primary.
Monday, December 6 - It’s a “Moon Gazer’s” night as our nearest astronomical neighbor continues to light up the night sky. Even from 383,000 km (238,000 miles) away! Don’t put away your telescopes and binoculars thinking there will be nothing to view, because one of the most “romantic” features on the lunar surface will be highlighted tonight.
The Sinus Iridium is one of the most fascinating and calming areas on the Moon. At around 241 km (150 miles) in diameter and ringed by the Juras Mountains, it’s known as the quiet name of “The Bay of Rainbows” but was formed by a cataclysm. Science speculates that a minor planet around 201 km (125 miles) in diameter once impacted our forming Moon with a glancing strike and the result of that impact caused “waves” of material to wash up to a “shoreline” forming this delightful C-shaped lunar feature. The effect of looking at a bay is stunning as the smooth inner sands show soft waves called “rilles”, broken only by a few small, impact craters. The picture is complete as Promentoriums Heraclides and LaPlace tower above the surface at 1800 meters (5900 ft.) and 3000 meters (9900 feet) respectively and appear as distant “lighthouses” set on either tip of Sinus Iridum’s opening.
For northern observers clamoring for brighter stellar action, look no further tonight than the incredible "Double Cluster" about four fingerwidths southeast of Delta Cassiopeiae. At a dark sky site, this incredible pair is easily located visually and stunning in any size binoculars and telescopes.
As part of the constellation of Perseus, this double delight is around 7000 light-years away and less than 100 light-years separates the pair. While open clusters in this area are not really a rarity, what makes the "Double Cluster" so inviting is the large amount of bright stars within each of them. Well known since the very beginnings of astronomy, take the time to have a close look at both Chi (NGC 884) and H Persei very carefully. Note how many colorful stars you see, and the vast array of double, multiple and variable systems!
Tuesday, December 7 - Today is the birthday of Gerard Kuiper. Born 1905, Kuiper was a Dutch-born American planetary scientist who discovered moons of both Uranus and Neptune. He was the first to know that Titan had an atmosphere, and he studied the origins of comets and the solar system.
Take the time tonight to once again return to the Moon and explore with binoculars or telescopes the area to the south around another easy and delightful lunar feature, the crater Gassendi. At around 110 km (70 miles) in diameter and 2010 meters (6600 feet) deep, this ancient crater contains a triple mountain peak in its center. As one of the most “perfect circles” on the Moon, the south wall of Gassendi has been eroded by lava flows over a 48 km (30 mile) expanse and offers a great amount of details to telescopic observers on its ridge and rille covered floor. For those observing with binoculars? Gassendi’s bright ring stands on the north shore of Mare Humorum… An area about the size of the state of Arkansas!
Wednesday, December 8 - Today in history (1908) marks "first light" for the 60" Hale Telescope at Mt. Wilson Observatory. Not only was it the largest telescope of the time, but it ended up being one of the most productive of all. Almost 100 years later, the 60" Hale is still in service as a public outreach instrument.
The waxing Moon will dominate the early evening skies, but tonight is an excellent opportunity for binoculars and telescopes to explore crater Tycho. Named for Danish astronomer, Tycho Brahe, this fantastic impact crater will be very impressive in even the most modest of optical aids. Spanning 85 km (56 miles), this lunar feature is very prominent and unmistakable in the southern hemisphere of the Moon. Tycho’s highly conspicuous ray systems support its impact crater theory and span hundreds of kilometers across the lunar surface. Tycho is also one of the youngest of the major features at an astounding age of only 50 million years old!
On January 9, 1968 Surveyor 7 (the last lunar robot of its kind) landed quietly on Tycho’s slopes at sunrise. Because previous Surveyor missions had provided the Apollo program with all the data necessary to their goals, Surveyor 7′s presence was scientific only. Two weeks later, when the Sun set on the landing site, Surveyor 7 had provided over 21,000 photographs, determined physical and chemical properties associated with the Southern Highland area and recorded the laser beams aimed toward it from two separate Earth observatories.
Thursday, December 9 - Southern Hemisphere viewers, you're in luck for a meteor shower. This is the maximum of the Puppid-Velid meteor shower. With an average fall rate of about 10 per hour, this particular meteor shower could also be visible to those far enough south to see the constellation of Puppis. Very little is known about this shower except that the streams and radiants are very tightly bound together. Since studies of the Puppid-Velids are just beginning, why not take the opportunity to watch? Viewing will be possible all night long and although most of the meteors are faint, this one is known to produce an occasional fireball.
Tonight the very gibbous Moon will command the skies and give unaided observers an opportunity to use their imaginations. Since the dawn of mankind, we have been gazing at the Moon and seeing fanciful shapes in the lunar features. Tonight as the Moon rises is your chance to catch “The Rabbit In The Moon”. The “Rabbit” is a compilation of all the dark maria. The Oceanus Procellarum forms the “ear” while the Mare Humorum makes the “nose”. The “body” is Mare Ibrium and the “front legs” appear to be Mare Nubium. Mare Serentatis is the “backside” and the picture is complete where Mare Tranquilitatus and Mare Fecunditatis shape the “hind legs” with Crisium as the “tail”.
See the Moon with an open mind and open eyes — and find the “Rabbit”!
For telescopes and binoculars, the lunar surface will provide a bright but superior view of crater Grimaldi. Named for Italian physicist and astronomer, Francesco Grimaldi, this deep grey oval is one of the darkest albedo features on the Moon – only reflecting about 6% of the light. Approximately 430 km (140-145 miles) long, it’s easy to spot along the terminator and just slightly south of the center of the lunar limb. Tonight is the best time to view its mountained walls, for they will disappear and Grimaldi will take on the appearance of a small mare in the light of the full Moon.
Until next week, may all your journeys be at light speed! ~Tammy
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