Monday, January 23, 2012

Weekly SkyWatcher's Forecast: January 22-28-2012

Greetings, fellow SkyWatchers! Are you ready for another week of what can be seen in the night sky? Then get out your telescopes and binoculars and let's begin...

Monday, January 22 - Tonight we're going in search of a Herschel 400 object. Wait until Orion has well risen.. Our mark will triangulate with Xi and Nu and point back in the direction of Betelgeuse. It's name? Collinder 83.. It is believed that it may have been observed by Hodierna before 1654, but its discovery is credited to William Herschel in 1784 and cataloged by him as H VIII.24. It hangs out in space some 3600 light-years away and most catalogs refer to it as NGC 2169 (Right Ascension: 6 : 08.4 - Declination: +13 : 57). At a rough magnitude of 6, it is very well suited to even smaller binoculars. Although diffuse nebulosity accompanies this 50 million year old cluster, even a small telescope should be able to resolve out its 30 or so stellar members. But no matter which optics you chose to look at this cluster with, one bright asterism will stand out - the number ‘37’ written in stars. Enjoy and write down your observations!

Tuesday, January 23 - Tonight is New Moon and I ask you to once again take out your telescopes and explore a region with me - M78 (Right Ascension: 5 : 46.7 - Declination: +00 : 03). It is for the very sake of amateur astronomy that I ask you to do this... And here is why.

On January 23, 2004, a young backyard astronomer named Jay McNeil was checking out his new 3" telescope by taking some long exposures of M78. Little did Jay know at the time, but he was about to make a huge discovery! When he later developed his photographs, there was a nebulous patch there that had no designation. When he reported his findings to the professionals, they confirmed it had no official designation and that Jay had stumbled onto something quite unique! It is believed that Jay's discovery was a variable accretion disc around a newborn star - IRAS 05436-0007. Little is known about the region, but it seems that it had been caught in a photo once in the past but never studied. Even the Digital Sky Surveys had no record of it!

Although Jay's discovery might not be bright enough tonight to be seen just south of M78, it is a variable and circumstance plays a big role in any observation. Before you think that being a backyard astronomer has no real importance to science - remember a teenager in a Kentucky backyard with a 3" telescope... Catching what professionals had missed!

Wednesday, January 24 - Today is the birthday of American solar astronomer Harold Babcock. Born in 1882, Babcock proposed in 1961 that the sunspot cycle was a result of the Sun's differential rotation and magnetic field. Would you like to have a look at the Sun? Although solar observing is best done with a proper filter, it is perfectly safe to use the "projection method”.

First off, NEVER look at the Sun directly with the eye or with any unfiltered optical device, such as binoculars or a telescope! We're not joking when we say this will blind you. Exposed film, mylar, and smoked glass are also UNSAFE. But don't be afraid, because we're here to tell you how you, too, can enjoy the Sun. A safe way to observe sunspots is to "project” an image of the Sun through a telescope or binoculars onto a screen. This can be a simple as cardboard, a paper plate, a wall or whatever you have handy. If you're using a telescope, be sure that finderscope is securely covered. If you'd like to try binoculars, just keep the cover on one of the two tubes. By using the shadow method, you will see a bright circle of light on your makeshift screen. This is the solar disc. Adjust the focus by moving the distance of the screen from your scope or binoculars until it is about the size of a small plate. If the image is blurry, use your manual focus until the edges of the disc become sharp. Even though it might take a little practice, you'll soon become proficient at this method and you'll be able to see a surprising amount of detail in and around sunspot areas. Happy and SAFE viewing to you all!

Today in 1986, the United States Voyager 2 was the first spacecraft to fly by Uranus, providing us on Earth some of the most outstanding photographs and information on the planet to date. After 10,382 days of successful operation, Voyager 2 still continues on towards the stars carrying a phonograph record of "The Sounds of Earth”.

Thursday, January 25 - Today is the birthday of Joseph Louis Lagrange. Born in 1736, this French mathematician made important contributions to the field of celestial mechanics. For now, let us return to Orion and have a much closer look at the blue/white giant - Beta Orionis.

The seventh brightest star in the sky is known by the name Rigel. Very little is known about its true distance from Earth, but it is widely accepted that it is around 900 light-years away. This white-hot star has a surface temperature of about 12,000 degrees Kelvin and is thousands of times more powerful than our own Sun. If it were as close to us as Sirius, it would shine with a light as bright as 20% of the full Moon! But look closely at the brilliant star... Intermediate sized telescopes under good conditions will find a 6.7 magnitude blue companion. Although it is not always an easy double star, you'll find it on the list for many challenges. But, chances are, we'll never see the C star that accompanies the B!

Even if you just view Rigel with your eyes tonight, marvel at this young and powerful star. When the light you see left this star, the Crusades had began...the Vikings were sailing to discover America...the Mayan Empire was beginning to crumble...paper was a new concept...and the very numbers we use today were just beginning to catch on!

Friday, January 26 - Today in 1962, the US space program launched a lunar probe named Ranger 3. Its mission was to image the Moon right up until impact, land a seismometer, study gamma rays and report on surface reflectivity of radar... But, it didn't happen. Two days after launch, the ill-fated Ranger 3 was on a runaway course towards the lunar surface when it received a reverse command and lost contact with Earth. As a result, it overshot its mark by 36,800 kilometers and still remains in heliocentric orbit.

Be out early tonight to catch the slender crescent Moon as we begin our journey designed to acquaint you with specific craters. Around midway on the terminator – the border between night and day - you will spot a conspicuous old crater called Langrenus. Named for Belgian engineer and mathematician Michel Florent van Langren, this handsome old crater stretches out over 132 kilometers in diameter. Look closely at its walls, they rise above the surface by 1981 meters and the deepest part of the floor drops down below 4937 meters - deeper than Mount Cotacachi in Ecuador is tall. Is the Sun rising over its brilliant east wall? If so, look closely and see if you can spot Langrenus' central mountain peak rising up 1950 meters. Then get out your skis, because that's as high as the base elevation in Jackson Hole, Wyoming!

If the timing is right, look along the terminator in the southern quadrant for ancient old crater Furnerius. Named for the French Jesuit mathematician George Furner, this crater spans approximately 125 kilometers and is a Lunar Club challenge. Power up and look for two interior craters. The smaller is crater A and it spans a little less than 15 kilometers and drops to a depth of over 1000 meters. The larger crater C is about 20 kilometers in diameter, but goes far deeper, to more than 1400 meters. That's about as deep as a coral will grow under the Earth's oceans! Although it has no central peak, its walls have been broken numerous times by many smaller impacts. Look at a rather large one just north of central on the crater floor. If skies are stable, power up and search for a rima extending from the northern edge. Shallower and less impressive than other craters, Furnerius will fade to obscurity as the Moon waxes. This flooded old crater has no central peak, but a much younger crater has punched a hole in its lava-filled floor. Look for the long "crack" extending from Furnerius' north shore to crater rim. Perhaps it was caused by the impact? Sharp-eyed observers with good conditions and high power will also spot a multitude of small craters within and along Furnerius' walls. For binocular viewers, try spotting crater Stevinus to the north and Fraunhofer to the south. .Keep in mind as you observe that our own Earth has been pummeled just as badly as its satellite. Can you imagine how differently Furnerius would look if decorated by forests and lakes?

Saturday, January 27 - On this day in 1967, tragedy struck at Pad 34. During a training exercise atop a Saturn 1B rocket, astronauts Command Pilot Virgil I. Grissom, Senior Pilot Ed White, and Pilot Roger B. Chaffee gave their lives to further human exploration of space as fire swept through their module. Named Apollo One, stop for a moment tonight to remember these brave souls. "They gave their lives in service to their country in the ongoing exploration of humankind's final frontier. Remember them not for how they died but for those ideals for which they lived.” (From the memorial on Launch Complex 34.)

During the early evening hours, take the time to view the northeast quadrant of the Moon and identify the emerging Mare Crisium. The "Sea of Crises” stretches out about 400 by 500 kilometers - an area about the size of the state of Washington. Mare Crisium is not only unique for its lack of connection with any other maria, but it is home to a gravitational anomaly called a mascon. This "mass concentration” might possibly be the fragments of the asteroid or comet whose impact with the lunar surface created the basin buried beneath the lava flow. The mascon creates an area of high gravity and causes changes in orbits of lunar probes. This excess gravity has even been known to cause low orbiting lunar satellites to either crash land or be flung out into space!

Sunday, January 28 - Today take the time to honor shuttle commander Dick Scobee, pilot Mike Smith, astronauts Ellison Onizuka, Judy Resnik, Ron McNair and Greg Jarvis, and teacher Christa McAuliffe. They were the crew onboard the Challenger when it exploded on this day in 1986. "We will never forget them, nor the last time we saw them, this morning, as they prepared for the journey and waved goodbye and slipped the surly bonds of Earth to touch the face of God.” (President Ronald Reagan) Godspeed...

Today also celebrates the birth of Johannes Hevelius (1611) who published the first detailed maps of the Moon. This evening let's honor our brave crew and Hevelius as we have a deeper look at crater Posidonius. Located on the north-eastern shore of Mare Serenitatis, this huge, old, mountain-walled plain in considered a class V crater. Spanning 84 by 98 kilometers, you can plainly see where Posidonius is shallow - dropping only 2590 meters below the surface. Tonight it will resemble a bright, elliptical pancake on the surface, but we'll return to study it later in the year.

Now that's you're a bit more familiar with the landscape, let's try working on some harder targets. For a telescopic and binocular challenge, step further south to visit one of the oldest features left on the visible lunar side. Start by identifying two prominent craters in the southeast quadrant - Metius and Fabricus. While viewing the area around them, note that Fabricus' walls actually intrude on Metius - pointing to a younger age of formation. Around Fabricus, but not including Metius, is the boundary of a mountain-walled plain extending into the terminator. High power will reveal many breaks in its hexagonal walls surrounding a floor marred by many smaller craters and fine fissures. This is Jannsen. Look for three prominent interior craters, as well as an ancient rima falling near the shadow's edge. It may not seem exciting, but remember Jannsen could go back to the time when the Moon first formed - more than four billion years ago!

Written by Tammy Plotner. If you liked this article, then you'll love the Night Sky Companion 2012!

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