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Icy Skies, Moons, And A Stellar Nursery

By Dave Grosvold

The Moon and Saturn at 12:00 AM CST Jan 6, 2010
With the colder weather and snow this time of year, astronomical observing is usually limited to fairly short sessions. Although the cold is hard on the observer, it is also hard on the equipment. So, naked-eye targets are ideal for winter observing. At midnight on Tuesday evening, the Moon rises very close to bright, pale yellow Saturn, and will be far below the Red Planet (Mars) in the sky. This week, the Moon enters Last Quarter at 4:39 AM CST on Thursday morning, so it won’t be quite as bright as it was on New Year’s Eve.

Saturnian Moons, 4:00 AM CST, Jan 7, 2010.
With the aid of a small telescope, you may also be able to see Titan, Saturn’s largest moon in the early morning hours if the sky is clear. At about 3:30 AM all this week,Saturn is high enough in the sky to rise above the “muck,” which is what astronomers call the thicker part of the atmosphere that we must look through when objects are close to the horizon. A view in a small scope will show Titan off to the right at about 2 o’clock. The image shown here will be reversed in the telescope’s field of view.

Early January is also a great time to observe the Great Orion Nebula, as it is in an ideal position by about 10:00 PM on these cold winter nights. The constellation of Orion rides high in the South-Southeast in late evening all week this week, and the Great Nebula is a special treat for anyone with a good pair of binoculars or small telescope. Orion is recognizable by his belt and sword.
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End 2009 With A Blue Moon

Fantasy image of a Blue Moon
Blue Moon Endings

The Full Moon on Thursday, December 31st marks a rare ending this year. There are normally 12 full lunar cycles in a year, but some years have 13. The thirteenth moon is sometimes known as the Blue Moon. Although different definitions place the blue moon at different times of the year, at least one definition places it at the end of the year.

A March 1946 article in Sky and Telescope magazine by James Hugh Pruett misinterpreted the 1937 Farmer’s Almanac to mean that the second full moon in a calendar month was called the Blue Moon. This “misinterpreted” definition of a Blue Moon has come into widespread use in recent years after it was revived on the January 31, 1980 installment of the popular radio program StarDate.

There are several other astronomical definitions for a “Blue Moon”, but the two cited above make this coming Thursday’s Full Moon a Blue Moon. By either definition, this only happens every few years. Just remember — it’s referred to as a blue moon, but the Moon won’t look blue — it will look the same as any other full moon.

In any event, it’s an appropriate way to punctuate not only the end of 2009, but the end of the only decade in a thousand years where we’ll refer to the year as “something-thousand-something” rather than the more common “nineteen- or twenty-something-something.” I guess a situation like that only happens “once in a very blue moon...”

Sky view looking east at 9:30 PM on Jan 2, 2010
The Wandering Stars

Planet, in Greek, means wanderer. These objects are so named because they appear to move from night to night against the fixed background of the stars. A feast of planets is visible in the evening sky this week, even with the glare of the Full Moon.

Jupiter, known as the King of Planets, will be visible as a bright object low in the southwest just after sunset. Jupiter sets in the west by about 9:00 PM, and will only be visible in the evening sky for another month or so. After that, it sinks below the horizon before sunset - too early to be seen for observers in our part of the world. Binoculars or small telescopes will reveal Ganymede, Callisto, Io, and Europa, the four brightest moons of Jupiter. Observing these at different hours of the night and on subsequent nights will show obvious movement with respect to each other and Jupiter. So far, scientists have discovered over sixty three moons orbiting the giant planet.

Neptune is approximately 1-1/2° lower toward the western horizon than Jupiter, and is much harder to spot. A small telescope will reveal it as an obvious disk with a blue-green cast, rather than as a point source. You can measure 1° on the sky by the width of your pinkie finger held at arm’s length. Neptune will set only about 6 minutes earlier than Jupiter.

Saturn presents a great observing target for those who might be awake in the early morning hours. Saturn’s rings are at just 4° from edge-on right now, so the planet looks much like a “spike in a ball” in small telescopes. The ring angle will open somewhat in 2010. Saturn will be rising in the east just before midnight, and will be appear to be a bright object with a slightly yellow cast. Small telescopes will reveal the rings and perhaps up to six of Saturn’s brightest moons — Titan, Hyperion, Rhea, Dione, Tethys, and Mimas. These will be stretched out along the same plane as the ring system. Of all the moons in the Solar System, Titan is unique in that it is the only one that has an atmosphere. Saturn has over sixty-one known moons.

Mars rises big and bright at about 8:00 PM and should be visible all night. Mars is in one of it’s close approaches (or opposition) to Earth during the month of January, and should be easy to observe. Small telescopes should show enough detail to see the markings or “canali” that lead early observers to believe there was an active civilization on the Red Planet. These markings were first observed by Giovanni Schiaparelli during the opposition of 1877, and he dubbed them canali, which is Italian for canals or channels. Improved astronomical observations in the early 20th century proved this to be false. Look for Mars in the east as a brilliant object with a ruddy hue. On Saturday, Jan 2nd, Mars and the Moon will rise together about 7° apart in the eastern sky. For reference, 7° of sky is about the width of four fingers held at arm’s length.
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How Dark Is It, Really?

You can download a very high-resolution version of this North America map as a zipped file here (2MB).
Over the past few months as we've begun investigating various possible sites for the relocation of Coleman Observatory, we've had several discussions about whether the potential locations had adequately dark skies or not. The best way to determine this, of course, is to spend quite a bit of time at each location at night, and evaluate the sky conditions.

To be accurate, this would normally need to be done over several week-long stretches during every major season of the year, to be sure that the evaluation included the diversity of weather that could be expected at each site, as well as how things like seeing and transparency at that specific location will impact the quality of the dark sky. The demands in terms of time and energy make it impractical for AOAS to undertake such an intensive evaluation of every possible site. So what can we do?

There are several sources of information regarding the general brightness of artificial lighting in North America. One of the best is the World Atlas of Artificial Night Sky Brightness. This is an excellent resource which can give a fairly good idea of the level of sky glow and light pollution for any location on the globe. There are a number of high-resolution individual maps that show the brightness intensity bases on a color code established to match the Bortle Dark Sky Scale. The Bortle Scale was originally created and published by John E. Bortle in an article in Sky and Telescope magazine in February, 2001. The Bortle scale is based on nine classes of dark sky, with Class 1 being the best, or black on the atlas maps, and Class 9 or white on the atlas maps.

There are very few areas of Class 1 (black) quality dark skies left in the continental United States, and none of them are in Arkansas or Eastern Oklahoma. In fact there are but a very few Class 2 (grey) places left in Arkansas and Eastern Oklahoma. The best we can probably expect is Class 3. However, how do we know for sure if a selected site is Class 3, 4, or even worse? Even the highest resolution maps from the World Atlas of Artificial Night Sky Brightness leaves us with quite a bit of doubt regarding specific locations because there just isn't enough information on the maps to make more than a general guess about the exact location of a site.
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New Partnership with KHBS 40/29

Drew Michaels will help draw visitors to our AOAS.ORG website every time he uses one of our "Astronomy from your Backyard" topics in his weather casts. Mutual online links will help both of us, and we say a big THANKS for asking us to assist in this effort, Drew!
We were recently contacted by Drew Michaels, Chief Meteorologist of TV 40/29, about starting a collaboration concerning some way to help folks who watch Drew's nightly weather forecasts and who have then occasionally called him with questions involving astronomy. He knew that AOAS could provide his viewers answers, and so, our idea for "Astronomy from your Backyard" was born. I write up simple instructions for viewers of 40/29, or for visitors to our website to see as well, which gives some simple steps for anyone who wants to try and witness, or experience any number of different objects and/or concepts associated with astronomy. I'll try to keep it simple for those who have never considered any of our topics before. For anyone who wants to know a little more about any given topic, Drew will mention our website every time he uses one of our topics, and then visitors to our site can find a somewhat more detailed description or definition of whatever that evening's topic happens to be in the "Astronomy from your Backyard" forum section. The use of the topics in Drew's weather casts will be non-regular, but should usually be aired up to two-or-three times each month. It should be a win-win situation for us both, by getting AOAS mentioned more frequently than we've ever been mentioned before, and by helping 40/29 viewers with their questions about "those pretty little things in the night sky".


We have now posted a permanent clickable link to a smaller image of this picture on our home page, and likewise, there is now a clickable link to AOAS from the 40/29 Weather page as well, just click on our logo and voila, your on our home page. It'll be a quick and easy way to learn about threatening weather when its in the area, and have you heard about the 40/29 Interactive Radar? It gives you, the viewer, the ability to USE the radar images yourself! You can zoom in to your town, or even down to your block with street level mapping to see just what the radar is seeing in near real time with a fast internet connection. Pretty cool stuff, there!

I hope we have entered into something here that will be a long-term effort and is mutually beneficial to both AOAS as well as to 40/29. I urge everyone to click on the link located on our home page, and then be sure to visit the Interactive Radar to try it out for yourself. We also look forward to everyone who takes the opportunity to come to our site and learn just a little bit about how to find, or how to identify, or just how to sit back and watch the universe as it passes overhead every clear night. ENJOY, EVERYONE!
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Wishing on Falling Stars

Backyard AstronomyThe usually productive Geminid meteor shower reaches its peak each year on the evening of December 13 & 14. In 2006 this is the middle of the week. Geminid meteors are occasionally bright, relatively slow compared to other showers during the autumn months, and best of all, they will restore your faith in meteor showers, at least, as long as the clouds stay away!

UPDATE: 12/14/06
The Geminids did NOT disappoint this year! AOAS members in attendance at Coleman Observatory were treated to rates of at least 90/hr, and the rates could have been as high as 110/hr. Along with the pleasantly warm temperatures, an exceptionally clear and steady sky, and lots of viewing the universe with our 14" computerized telescope, we all enjoyed ourselves, some until nearly 2:30am. We won't likely see another meteor shower this good again for a while, so if you missed this one, you missed a really good one!

Look to the ENE horizon at about 8:00pm on Wednesday, December 13, 2006. Orion will be to the SE of Gemini, and about as high above the horizon. Kick back in a lounge chair or in a thick, warm sleeping bag and just stare at as large of an area of sky as you can take in. Expect to see 50 meteors every hour originating out of the area near Castor early on. Rates will increase to 70/hr and may occasionally reach 90/hr as Gemini rises to near the zenith around 1:00am on Dec 14.
November 12, 1833 was just another day, but that night brought the end of the world! On that evening the greatest meteor STORM in human history occurred with an estimated fall-rate of up to 300,000 PER HOUR! Every place that witnessed the spectacle saw people fearing that the end of the world was at hand. This gigantic event was witnessed from Europe across the North Atlantic and well into the middle of North America, and it is said to be solely responsible for the birth of modern meteor science.

The 1833 outburst of activity was from the Leonid meteor shower. The Leonids fall from an area in the "head" of the constellation Leo every November 17-18. Even the east coast of the US saw rates of fall in 1833 on the order of a few thousand per hour, and needless to say, most people who witnessed that event would never be the same again. Many were convinced that what they were seeing was a direct effect from the Hand of God.

At the time, science had only recently begun to accept the notion that meteorites were pieces of rock and metal that fell to Earth from outer space. It simply seemed too counter-intuitive to be true, at least as far as most people were concerned, and there were some influential individuals in that group. One such person, a scientist who was also our second president of the United States, Thomas Jefferson, supposedly remarked after a recent fall of a small stone meteorite in Connecticut, "I'd [sooner] believe that two Yankee professors would lie than [accept] that stones would fall from heaven."

One of three images I took of the Leonid meteor shower of November 18, 1998, the night of 100 fireballs! This one ended in a "terminal burst" which is when a meteor briefly fades away and then suddenly bursts into light as it is completely consumed by the frictional heating with air molecules. Can you see the faint red horizontal streak of color near the trees? That's a "train" of still glowing air molecules left over from another recent bright fireball only minutes before I took this image.
This statement is believed to simply be folklore, but it reflects the feelings of the majority of laypeople and even most scientists of the day. Sometime around that same period in history, the connection between meteors and comets was also established. Those who studied the orbital motions of comets recognized that the thousands of meteors which fell in 1833's Leonid storm bore a remarkably close resemblance to the orbittal path of comet Temple-Tuttle. And, it just so happened that the comet was making its normal 33-year periodic visit to the inner solar system at around the same time. The Leonids sometimes produce HUGE meteor storms about every 33 years when Temple-Tuttle returns. Suddenly, here was the connection between meteors and comets right in the face of all who understood orbital mechanics based on mathematical formulae. Now we knew...annual meteor showers originated with the passages of comets through the inner solar system.

Meteors from ALL showers are simply that dusty material shed from their cometary parent-bodies as they pass through the inner solar system.
Earth's orbit takes us once around the Sun each year. If a comet has passed through the area where our orbit lies, we pass through dust particles left behind from that comet. We pass through the dust trails of several past comets every year.
I apologize for my drawing above, but without it I'd be forced to try and help you envision where the Geminid meteor shower comes from with mere words.

COMETS 101

A basic understanding of comets is needed here, and we must start with the elemental make-up of the comet itself. Comets are chunks of frozen water-ice and a wide mix of frozen gasses, as well as millions of tons of small pieces of dust and metal fragments. A typical comet is usually about the size of a large city, but some are thought to be up to many dozen miles in diameter. The general description of comets being huge "dirty snowballs" is absolutely accurate, and yet they are some of the smaller members of our solar system. Their apparent size is covered in the "read more" area.

Sometimes comets are set in motion from their origination point 10-billion miles away, towards the general direction of our Sun by a passing star or a gravity wave. Once this occurs, nothing can stop it, and the (frequently) odd-shaped comet nucleus will begin to form a dusty and gaseous halo around itself as the volatile frozen gasses are heated by the Sun's energy as the comet draws nearer. The Sun's solar wind is always blowing outward in all directions, and this energy causes the dust and gas to be swept backward away from the comet's head causing the characteristic "head-and-tail" appearance. No matter which direction the comet is moving, the energy from the solar wind ALWAYS forces the tail to point away from the Sun. A comet's tail points away from the Sun when the comet is inbound, and then the head actually follows the tail after it rounds the Sun and once again moves outbound through the middle-to-outer solar system.

Click read more for the rest of this story.

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Waiting for the Stars

Backyard Astronomy
Image by Bob Moody; Canon PowerShot A10 thru a 12.5" Dobsonian
For years I would occasionally find myself out in the night air, scurrying around to get some extremely important bit of nothing done, never once looking up to see the night sky. Always my eyes would be looking down to the Earth so I wouldn't stumble or fall in the darkness that made up my world.

Then one night as I walked out into the night I did happen to look up just as the full moon appeared from behind a passing cloud, lighting up the place where I stood in it's cool, white glow. The sight was an awesome thing to behold for a then ten-year-old boy, so I just kept looking up. Soon I noticed the moon was not the only thing in the heavens, but just one of the thousands of objects that overwhelmed my senses. Funny how a child discovers his or her world in an instant of wonderous recognition.

It's also funny how you can go through your days always doing the same things in the same old ways until something changes your awareness. From then on, nothing is ever the same again as you begin your quest for knowledge and understanding of this universe we all share. Essentially, that's what happened to me on that moonlit night. It was then I began to realize that there is so much more to living than merely the day to day routines we all find ourselves in. Our lives always seem to get into a groove, or rut as it were, and that rut just keeps getting deeper until one day we stop looking down. It's at that point, when we start to look up, that we realize how deep that rut really is, and how easy it is to climb out of it if we just keep looking up.

So now I have a thought for all of you who find yourselves looking down into the rut. The next time you go out at night, be a child again, and stop where you are, stand still for a moment, and look up. If you do this every time you wander under the night sky, you'll be surprised at how quickly you'll find yourself actually waiting throughout the daylight hours for the stars to come into view each night!

Enjoy the view

Ed Wemmerus, Vice-President AOAS - 2006
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Start an Astronomical League observing program tonight!

Backyard AstronomySent by - John Jardine Goss

Secretary, Astronomical League

After finally finding some time under the stars, have you ever thought, "What should I observe? There's so much up there!"



The Astronomical League offers nearly 30 observing programs to help in just that situation. Some are designed for the novice such as Constellation Hunters, Universe Sampler, and Lunar Clubs. Other programs, including the Messier, Urban, and Planetary Observer Clubs, are better suited for intermediate observers. More experience deep sky hunters can hone their skills with the tougher selections of the Herschel, Arp Peculiar Galaxies, and Galaxy Groups and Clusters Clubs. Truly, there is a program for everyone!

Upon completion of each club, the observer is presented a certificate suitable for framing and a nifty lapel pin. These lists are a low stress way to enjoy the many wonders of the night sky.

Check out which program is right for you! Visit the League Observing pages here
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My Quest for a Messier Certificate by Jon Stone

Backyard AstronomyJon Stone (TexasJagsFan) came to AOAS in January 2005 and immediately wanted to join our club. As we were observing at Coleman Observatory over the weekend of April 1st and 2nd, I watched as he worked on his Messier list, something that only a few other AOAS members have begun to do. Upon asking him to write a story about his efforts at earning his Messier Certificate, he quickly agreed and we began working on this story, he writing and me editing. Jon's enthusiasm and excitement will hopefully inspire those members who've already started their lists to finish them, but it might also encourage others who haven't started a list to begin their own. I have no doubt that Jon will earn his Honorary Messier Certificate on time as described below. Bob

A few years ago when I bought a 2.4" Meade telescope from Wal-Mart, I began using it to observe the moon, and sometimes look at things across a lake that we lived on. Later we moved to Amarillo, TX where I knew someone with the astronomy club there. He showed me several of Messier's objects, and also told me about a list of these objects and a logsheet that you could fill in and send off for a certificate when you had found all 110 of Messier's objects. So, I started the list with my telescope but I was disappointed that I couldn't find any galaxies. Later I was told that I might not be able to find any galaxies in the telescope I started with, and I gave up.

AOAS member Jon Stone at Coleman Observatory with his 8" Celestron Dob in April 2005.
It would be about a year before I would live someplace where there was another local astronomy club. That's when we moved to Van Buren. I attended the January 2005 meeting of the Arkansas Oklahoma Astronomical Society intending on joining where I met Bob Moody and others. I believe it was Bob that I was talking to about wanting to get a bigger telescope. He showed me an ad for Astronomics from where I would eventually buy an 8 inch Celestron Dobsonian. I then decided I could start my Messier list again.

Currently, I have found 23 of the 110 Messier objects, since I re-started on 3/27. Those 23 objects are: M1, M3, M13, M35, M36, M37, M38, M41, M42, M43, M44, M45, M51, M57, M65, M66, M67, M78, M81, M82, M97, M104, and M109.

I started the list on 3/27 by finding M42, Orion's Nebula, and the most recent object that I found on 4/2 were the galaxies M81/82.
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How to Find an Asteroid

Backyard Astronomy
Asteroid 1/Ceres - The first asteroid discovered, Ceres shows its best face to date in this Hubble Space Telescope Near-Infrared image. At nearly 600 miles in diameter, not even Hubble can see much detail, yet it's obvious that Ceres is spherical. Marcus Blair's observation and description of Ceres appearing as a small "disk" is an accurate description. - Bob Moody
We’ve had great, clear skies the last couple of nights, so I’ve been doing a lot of observing. On Monday night, despite the nearly half moon, I spotted several Messier objects to add to my log. All of this is made much easier by my Meade ETX 90 scope with the “go to” feature. It’s becoming second-nature to set up this scope and have it locked on and accurate within a few minutes. The only trade-off is the lack of aperture, but a true beginner like me can greatly benefit from the go-to function.

Despite what some might say, having a go-to scope is not cheapening the experience for me, but is enriching it. I struggled for years to find things in the sky. Now, I am able to find them, but best of all, I learn and remember their positions. For example, once I finally locate M82 with the ETX, I will be able to find it next time without the go-to feature because I know (a) what it looks like and (b) where to find it.

Monday night I decided to try something entirely different, so I was scrolling through the AutoStar controller’s memory banks of thousands of objects. I came across the “Asteroids” category and wondered whether I could find one. I knew Ceres is the largest known asteroid, so I told the scope to go to it.

The scope slewed to an area containing several star-like objects. Nothing was obviously an asteroid. I looked at the area with different magnifications and finally decided the brightest object in the field was Ceres, but I wasn’t sure.
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The Sky's "NEW" Star - Comet C/2004 Q2 Machholz

Backyard AstronomyComets come, and comets go. Comet C/2004 Q2 (Machholz) is the current "star" of the evening sky.

AOAS member Mike Holloway's image of Comet C/2004 Q2 Machholz from Van Buren, AR.
Comet C/2004 Q2 Machholz is a rarity in comets these days. It wasn't discovered by an automated search program. Instead, it was discovered by amateur astronomer Don Machholz of California. Machholz was performing a "sweep" for comets in an area closer to our Sun than what an automated army of asteroid detection programs usually searches. Mr. Machholz noticed a faint "fuzzy" last August 2004, and then properly notified the appropriate entities for reporting comets and was given credit for his sole discovery of this comet that now bears his name. This is one of several areas where amateur astronomers are still able to make discoveries and observations that are welcomed by the professional astronomical community.

Holloway's Comet Machholz and the "Pleiades" cluster taken Jan 7, 2005
Members of the Arkansas Oklahoma Astronomical Society's Executive Committee were meeting at the Society's Coleman Observatory on Saturday, January 8th. After the meeting had adjourned around 7:30, members stepped outside to use their "double-barreled BIG GUN", the 20 X 100 binoculars that the club purchased last summer. The comet was located about 1-2 degrees west (above) the Pleiades star cluster in the constellation Taurus. The Pleiades are also referred to as the "Seven Sisters". Comet Machholz was a relatively easily seen "smudge" of light near the cluster with the naked eye, but through the big binoculars the comet filled the field of view to overflowing. The core of the comet's head was nearly stellar in appearence and the tails were spread away from the head down (east) and north (left) of the nucleus.

Anyone with binoculars or a small telescope may find this new comet by first locating the Pleiades on any clear night shortly after darkness has fallen. Face east and look nearly straight overhead for the Pleiades. Trace a line to your left towards the "pole star", Polaris, and scan with your eyes or any optical aid in and along that line between Polaris and the Pleiades. The comet will be an easily seen, large, greyish-green haze in any telescope or binoculars, and from dark skies (away from city lights) it may be located with your eyes as a small and faint spot along that trajectory. The comet will continue moving towards Polaris at about 1-2 degrees per day over the next several weeks and will remain a beautiful object for probably 2-3 more months.

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