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Seeing in the Dark with Spitzer

NASA Space Placeby Patrick Barry and Tony Phillips

Artist’s rendering of brown dwarf OTS44 with its rotating planetary disk. (Click for larger image.)
Have you ever gotten up in the middle of the night, walked to the bathroom and, in the darkness, tripped over your dog? A tip from the world of high-tech espionage: next time use night-vision goggles.

Night vision goggles detect heat in the form of infrared radiation—a "color" normally invisible to the human eye. Wearing a pair you can see sleeping dogs, or anything that’s warm, in complete darkness.

This same trick works in the darkness of space. Much of the exciting action in the cosmos is too dark for ordinary telescopes to see. For example, stars are born in the heart of dark interstellar clouds. While the stars themselves are bright, their birth-clouds are dense, practically impenetrable. The workings of star birth are thus hidden.

That's why NASA launched the Spitzer Space Telescope into orbit in 2003. Like a giant set of infrared goggles, Spitzer allows scientists to peer into the darkness of space and see, for example, stars and planets being born. Dogs or dog stars: infrared radiation reveals both.

There is one problem, though, for astronomers. "Infrared telescopes on the ground can't see very well," explains Michelle Thaller, an astronomer at the California Institute of Technology. "Earth's atmosphere blocks most infrared light from above. It was important to put Spitzer into space where it can get a clear view of the cosmos."

The clear view provided by Spitzer recently allowed scientists to make a remarkable discovery: They found planets coalescing out of a disk of gas and dust that was circling—not a star—but a "failed star" not much bigger than a planet! Planets orbiting a giant planet?
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Last Basics of Astronomy Classes for Summer 2005

Education OutreachThe Arkansas Oklahoma Astronomical Society announces the summer schedule for classes in our Basics of Astronomy. These classes will be held at the club's Coleman Observatory located 8 miles NW of Van Buren, AR, on Tuesday OR Thursday evenings.

Update Notice: The July classes are filling up and begin July 5th and 7th. To attend the July classes, prospective students must PRE-register and payment must be received by July 2nd. Please call for more information on the July classes. Click on Coleman Observatory (in the Main Menu) for a map to the site.

These classes will be 5 weeks in length and class begins at 6:00 pm on the night of the student's choosing. There is a limit of 10 people to each class size, and there must be an adult attending with any students of at least 7 years of age and up to 17 years of age.

These classes will be the last offered until next summer, so make certain to contact us as soon as possible if you'd like to attend. These classes will begin on either Tuesday, July 5th, or Thursday, July 7th, and again will run for 5 weeks through August 2nd and August 4th. Students must PRE-register for these second classes and payment must be received through Coleman Observatory by July 2.

This will be the first time that books will be used for these Basics of Astronomy classes. Two wonderful books are available from DK publishers and will be included in the price of the class. The books are "Children's Night Sky Atlas" (96 pgs) and "Universe" (64 pgs), both by Eyewitness books. Don't let the 'Children' in the title fool you. Every adult will appreciate these classy stellar images and constellation figure overlays. They are simply the best way to show which stars belong to which constellation that I've ever seen. These books complement each other very well with the "Atlas" constellation images and star-fields helping you learn to identify by seeing, along with clear representations of the different types of telescopes and how to use them, the motions of the stars and planets, and MUCH more. The "Universe" gets more involved in the mechanics of astronomy by revealing how professional astronomers use major observatory telescopes to study the light from distant stars and galaxies by the process of spectroscopy.

NEW - The course Outline can be dowloaded from this URL: http://www.aoas.org/filemgmt/singlefile.php?lid=28.
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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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Hope for the Hubble?

NASA Space PlaceBy Richard Tresch Fienberg

NASA's new chief, Michael D. Griffin, has told the Hubble servicing team at the Goddard Space Flight Center in Maryland to resume preparations for a possible shuttle flight to upgrade the orbiting observatory. Although a decision on returning astronauts to Hubble won't be made until after at least two successful shuttle missions to the International Space Station, the telescope's prospects look better now than they have at any time since Griffin's predecessor, Sean O'Keefe, abruptly canceled Hubble servicing in January 2004 — a decision that outraged astronomers, key members of Congress, and the public.

At his Senate confirmation hearing in early April, Griffin said he would consider reauthorizing a Hubble house call once the shuttle was flying again. But after just two weeks on the job he called a press conference to announce a two-month slip in the first post-Columbia launch, from mid-May to mid-July. This means that the second of two "return-to-flight" missions won't occur before September. By then there may not be enough time to mount a servicing mission that would reach Hubble before its electronics give out. So, said Griffin, "what we're going to be doing is getting the...folks at Goddard started on the work that they would have to do if a servicing flight can yet be done."

Griffin reiterated that a robotic servicing mission, once offered as a less risky alternative to a shuttle flight, is no longer under consideration. Robotic servicing "is just not feasible within the time and the money that we have to allow for it," said Griffin. "So that's off the table."

Astronauts have serviced Hubble four times between 1993 and 2002, replacing failed components and installing new instruments. If they do it again, they'll have three main goals. One is to extend the spacecraft's operational lifetime by replacing its onboard gyroscopes and batteries. Another is to upgrade the telescope's scientific capabilities by installing a new camera and spectrograph. The third and most important task is to attach a retrorocket module that will steer Hubble to a harmless splashdown in the Pacific Ocean at the end of its mission early in the next decade. If the shuttle's return to flight doesn't go as planned, or if something else happens to preclude servicing Hubble, NASA probably will instead fly a limited robotic mission just to attach the deorbit module.
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Starting an Online Observing Log

General NewsIt seems amateur astronomers who are just beginning to observe face a number of challenges, but maybe none is as monumental as the task to learn HOW to observe effectively. I decided maybe there was something I could do about that, since I have spent a great deal of time bumping my head as I cruise the stars.

Since last summer, I’ve been keeping a Messier log in my home computer using the logsheets provided on the AOAS Web site. I like those sheets, but I somehow always manage to procrastinate when it comes to logging my finds. I decided it would be easier if my logsheets were available at work and elsewhere instead of just at home. The only way to accomplish this task was to keep my observing log online.

Then I realized that the effect of this project would be twofold – first, I would have access to my observing log from any computer, but second and more importantly, other novices can read about my experiences and get help. Maybe someone else is thinking about finding Ceres. I have done it. They can read my site and find out how to accomplish this. I can also share helpful sites and lead people to the AOAS site, so my log also becomes a public relations tool.
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New Moon Found in Saturn's Rings

Lunar & Planetary
The international Cassini spacecraft has spied a tiny new moon hidden in a gap in Saturn's outer ring, scientists said.

The moon was spotted earlier this month in the center of the Keeler gap, making waves in the gap edges as it orbits. Tentatively called S/2005 S1, the moon measures four miles across and is about 85,000 miles from the center of Saturn.

More observations are needed to determine the shape of the moon's orbit, but preliminary findings show it is in the middle of the gap, Joseph Spitale, a planetary scientist at the Space Science Institute in Boulder, Colo., said Tuesday.

S/2005 S1 is the second moon known to exist within Saturn's shimmering rings. The other is Pan, which orbits in the Encke gap. All of Saturn's other known moons are outside the main ring system.

The $3.3 billion Cassini mission, funded by NASA and the European and Italian space agencies, was launched in 1997 and took seven years to reach Saturn.

Cassini/Huygens Home Page

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Question about water and space

Lunar & PlanetaryHey everybody. I gave presentations to my daughters 4th grade science classes yesterday and as usual, the kids never fail to amaze me with their level of knowledge and the questions that they ask. I had talked briefly about the presence of ice in comets and in the rings of Saturn. I was then asked where the water comes from to which I had no answer. Can anybody tell me how water is created and does any reside in the innerstellar world of space? They also asked what the effect to earth would be if Jupiter blew up and what color would Uranus be if it wasn't blue. There were numerous extremely good questions and although I could answer most, I will need to study up on the finer details of the planets. I was lucky enough to do a little research before hand and know that Jupiter is now up to 63 moons. I had a great time and the kids seamed to really enjoy it as well. The 50 minutes for each class passed by in an instant. One class, I was only a 4th of the way thru my presentation and the teacher informed that there were only 10 minutes left. Well, lunch break is over but if anybody can help me out, I would appreciate any contributions to the water questions.

Answers as best I can give them.........by Bob Moody

Water exists by the combination of the elements that make it up, namely, one atom of oxygen bound to two atoms of hydrogen. We know that hydrogen is the most abundant element in the universe, and we believe we understand that oxygen came about as a result of the deaths of so-called "first-generation stars". These are stars which were made up almost exclusively of hydrogen and helium, with a thin sprinkling of lithium. These three were the original elements from the creation of the universe, and everything on the Periodic Table of Elements above these three elements have come about as the result of large first-generation stars which went supernova and literally "cooked up" the heavier elements during those supernova explosions. It takes titanic explosions with super-hot temperatures to forge the heavy elements.

Click "Read more" for the rest of this explanation.....
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First Planet Outside Solar System Observed


LOS ANGELES - New images taken of an object five times the mass of Jupiter confirm that it is a giant planet closely orbiting a distant star, an international team of astronomers reported. The team of European and American astronomers said this is the first time a planet outside of our solar system has been directly observed — a claim other scientists have also made.

The team first spotted the object last year as a faint reddish speck of light circling a dim brown dwarf — or failed star — 225 light-years away from Earth near the constellation Hydra. At the time, scientists guessed the faint light was a planet, but said further observation was needed.

The discovery touched off a debate over whether the object was actually a planet or a background star. Since the mid-1990s, scientists have discovered more than 130 of these so-called extrasolar planets by indirect means, but observing them directly has proved difficult.

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The Backyard Astronomer's Guide - Answers Galore

Book ReviewsThe Backyard Astronomer's Guide - By Terence Dickinson & Alan Dyer - Firefly Books 2002

There are only a very few books that get me excited, that make me want to read every word, and that I would recommend to anyone and everyone.The Backyard Astronomer's Guide is one I'll refer to and recommend often for probably the next 20 years or more.

I usually don't recommend a book as highly as I'm going to recommend this book. If you are an amateur astronomer, of ANY level of experience or expertise, you will find and learn things from this book that you never knew before, and you're also likely to find better explanations, illustrations and/or tables for most of the other things that you have seen before.

Terence Dickinson and Alan Dyer are both well known authors and writers, and their collaboration on this book is likely to cause The Backyard Astronomer's Guide to be regarded as a classic for a long time to come. At the turn of almost every page, I have been either knocked out by the imagery or illustrations, or I've marveled at the way the clear and concise, even poetic text, takes me to some deeper level of understanding on so many different subjects. It even gave me an image of our solar system's orientation as it relates to the plane of our Milky Way galaxy that I've never seen represented before. I'd wondered what our orientation was on so many occasions over the last 20 years, and in this book, I finally found it! In the plane of our galaxy, we are about 2/3 of the way out from the center to the outer edge. Our solar system's plane is tilted at about 65 to 70 degrees perpendicular to the plane of the galaxy. That's why we see the Milky Way appear differently in the summer versus winter, and it's also why the direction of the Milky Way runs N-S directly overhead at midnight on the first day of summer versus the E-W direction overhead at midnight on the first day of winter.

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Asian Tsunami Seen from Space

NASA Space Placeby Patrick L. Barry

This December 26, 2004, MISR image of the southern tip of Sri Lanka was taken several hours after the first tsunami wave hit the island. It was taken with MISR’s 46° forward-looking camera.
When JPL research scientist Michael Garay first heard the news that a tsunami had struck southern Asia, he felt the same shock and sadness over the tremendous loss of human life that most people certainly felt. Later, though, he began to wonder: were these waves big enough to see from space?

So he decided to check. At JPL, Garay analyzes data from MISR—the Multi-angle Imaging SpectroRadiometer instrument aboard NASA's Terra satellite. He scoured MISR images from the day of the tsunami, looking for signs of the waves near the coasts of India, Sri Lanka, Indonesia, and Thailand.

Looking at an image of the southern tip of Sri Lanka taken by one of MISR's angled cameras, he spotted the distinct shape of waves made visible by the glint of reflected sunlight. They look a bit like normal waves, except for their scale: These waves were more than a kilometer wide!

Most satellites have cameras that point straight down. From that angle, waves are hard to see. But MISR is unique in having nine cameras, each viewing Earth at a different angle. “We could see the waves because MISR's forward-looking camera caught the reflected sunlight just right,” Garay explains.

In another set of images, MISR’s cameras caught the white foam of tsunami waves breaking off the coast of India. By looking at various angles as the Terra satellite passed over the area, MISR’s cameras snapped seven shots of the breaking waves, each about a minute apart. This gave scientists a unique time-lapse view of the motion of the waves, providing valuable data such as the location, speed, and direction of the breaking waves.

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