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Stardust Comet Particles Tell Tales of Fire and Ice

Lunar & PlanetaryThe wonderfully successful Stardust mission to retrieve cometary and interstellar dust grains is now beginning to reveal to scientists the secrets it was sent to find. It re-entered Earth's atmosphere at a near-record speed of almost 30,000 mph on January 15, 2006, with the pristine dust particles of comet Wild 2 (pronounced 'Vilt 2') as well as other particles gathered from between the planets on its way to the comet safely packed away deep inside.

Once it had landed at the Dugway Proving Grounds in Utah, it was recovered, transported to a special lab at a NASA facility in Houston, and research is now underway on the first of these exciting never-before-seen-particles.
Brilliantly illuminating the countryside over the Pacific Northwest and Northern Nevada and Utah, Stardust announces its return to Earth after a spectacularly successful cometary material return mission.

Early reports from Stardust mission scientists reveals that there are materials found within the dust grains gathered from Comet Wild 2 that had to have formed in very high-temperature conditions, namely, the mineral olivine. This was totally unexpected as Stardust Principal Investigator Donald Brownlee of University of Washington at Seatlle explains."The interesting thing is we are finding these high-temperature minerals in materials from the coldest place in the solar system." Most AOAS club members will remember some of the meteorites that I've brought to club meetings from time-to-time, and olivine is a common ingredient in meteorites and in many Earth minerals. Another well-known name in meteoritical research is Michael Zolinsky who happens to be the curator and a co-investigator on the Stardust team says, "[finding] high-temperature minerals...supports a particular model where strong bipolar jets coming out of the early sun propelled material formed near to the sun outward to the outer reaches of the solar system."

Tiny fragment of the high-temperature mineral olivine found as one of the comet dust grains imbedded within the aerogel material on the Stardust mission.
Olivine is one of the most common minerals in the universe. It's the primary ingredient in the green beach sands found on some Hawaiian beaches, and they are, of course, formed from volcanoes. Quite surprising to find such a mineral within cometary dust.

While olivine is a component of iron and magnesium, as well as other elements, the olivine in the dust taken from the Wild 2 samples is also rich in calcium, aluminum, and titanium.

The remarkable material which performed the task of capturing these dust grains and interstellar particles is called Aerogel, and is about 1000 times less dense than glass. To look at it, one can easily see where it gets the nickname "solid blue smoke".

Click "read more" for an image of Aerogel, more images of cometary particles, and links to websites to learn more about Stardust
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Mt Magazine and Amateur Astronomy

General NewsArkansas' highest point is Mt. Magazine at an altitude above sea level of 2,753 feet. With a new multi-million dollar lodge and cabins set to open (hopefully) on May 1st, and their Grand Re-Opening for the public on May 20th, amateur astronomers are working with the Park Rangers there to help make the park more astronomy-friendly for all! Visit their Mt Magazine website here for more information.

Arkansas' premier state park and lodge will open to the public on May 1st and the re-opening on May 20th. This image is from the front yard of Cabin 13 (soon to be re-numbered 14) This was a three-bedroom cabin where two or three amateurs might stay to share the costs.
It's a popular misconception, but you hear it all the time...."Mt Magazine is the highest point between the Rocky Mountains and the Appalachians". While there are several specific points on a map that are slightly higher between America's two major mountain ranges, Mt. Magazine is unique. It's the highest point in AR, its surrounded by natural beauty, and it's accessible to amateur astronomers who want a great observing site.

On February 16th, AOAS Education Director Dr. Chuck Larson and myself attended a meeting with Wade Van Arsdale of the Little Rock area. Wade is a member of the Central Arkansas Astronomical Society (CAAS) and serves the club on their board. We met to discuss how Mt Magazine might better be suited to cater to amateur astronomers. The meeting was very good and we heard some encouraging words from the Park Interpreter about how some upcoming improvements at the park might indeed be helpful to amateur astronomers. Their Park Interpreter, Don Simons, took us all around for a guided tour of the entire park specifically to talk about how amateur astronomy could be better enjoyed at the park. He also made the suggestion that we might want to attend their Grand Re-Opening set for May 20th. I suggested that we might use some telescopes to do a little solar observing right in front of the Visitor's Center that day and he liked the idea.
From left to right, Dr. Chuck Larson, Bob Moody, and Wade Van Arsdale.

The President of CAAS, Stacy Edwards, has started a YahooGroup! page to help all Arkansas amateur astronomers meet and discuss all things astronomical. This is an excellent idea, and I hope that if you are an amateur astronomer wanting to see more cooperation happen right here at home, then you should definitely join this group yourself. I've met some other amateurs in our immediate area, but there might be a couple of hundred or more in the entire state and we all can use this YahooGroups! site to organize some cooperative events here close to home. That'd be a good way to begin planning some type of state-wide effort at holding a large star party somewhere in the state. An alternative to that might be to help any events that are already planned to become bigger and better. The ArkLaTex star party at Nashville, AR would be one example. It wouldn't be beyond what several clubs could do together to host something that's 2-4 days in length and with numerous speakers and a large number of vendors. These are the types of things that can be accomplished with the new Arkansas_Astronomy YahooGroups! web page, and even more over time.

Click read more for more images and the rest of this story.

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Micro-sats with Macro-potential

NASA Space PlaceBy Patrick L. Barry

The Space Technology 5 mission will test crucial micro-satellite technologies.
Future space telescopes might not consist of a single satellite such as Hubble, but a constellation of dozens or even hundreds of small satellites, or "micro-sats," operating in unison.

Such a swarm of little satellites could act as one enormous telescope with a mirror as large as the entire constellation, just as arrays of Earth-bound radio telescopes do. It could also last for a long time, because damage to one micro-sat wouldn't ruin the whole space telescope; the rest of the swarm could continue as if nothing had happened.

And that's just one example of the cool things that micro-sats could do. Plus, micro-sats are simply smaller and lighter than normal satellites, so they're much cheaper to launch into space.

In February, NASA plans to launch its first experimental micro-sat mission, called Space Technology 5. As part of the New Millennium Program, ST5 will test out the crucial technologies needed for micro-sats—such as miniature thrust and guidance systems—so that future missions can use those technologies dependably.

Measuring only 53 centimeters (20 inches) across and weighing a mere 25 kilograms (55 pounds), each of the three micro-sats for ST5 resembles a small television in size and weight. Normal satellites can be as large and heavy as a school bus.

"ST5 will also gather scientific data, helping scientists explore Earth's magnetic field and space weather," says James Slavin, Project Scientist for ST5.

Slavin suggests some other potential uses for micro-sats:
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Snowstorm on Pluto

NASA Space Placeby Dr. Tony Phillips

This artist's rendering shows how Pluto and two of its possible three moons might look from the surface of the third moon. Credit: NASA/ESA and G. Bacon (STSci)
There's a nip in the air. Outside it's beginning to snow, the first fall of winter. A few delicate flakes tumble from the sky, innocently enough, but this is no mere flurry…

Soon the air is choked with snow, falling so fast and hard it seems to pull the sky down with it. Indeed, that's what happens. Weeks later when the storm finally ends the entire atmosphere is gone. Every molecule of air on your planet has frozen and fallen to the ground…

That was a snowstorm—on Pluto.

Once every year on Pluto (1 Pluto-year = 248 Earth-years), around the beginning of winter, it gets so cold that the atmosphere freezes. Air on Pluto is made mainly of nitrogen with a smattering of methane and other compounds. When the temperature dips to about 32°K (-240°C), these molecules crystallize and the atmosphere comes down.

"The collapse can happen quite suddenly," says Alan Stern of the Southwest Research Institute. "Snow begins to fall, the surface reflects more sunlight, forcing quicker cooling, accelerating the snowfall. It can all be over in a few weeks or months."

Researchers believe this will happen sometime during the next 10 to 20 years. Pluto is receding from the warmth of the Sun, carried outward by its 25% elliptical orbit. Winter is coming.

So is New Horizons. Stern is lead scientist for the robotic probe, which left Earth in January bound for Pluto. In 2015 New Horizons will become the first spacecraft to visit that distant planet. The question is, will it arrive before the snowstorm?
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"Stars in the Parks" 2006 Kicks Off

Education OutreachAOAS' annual "Stars in the Parks" public observing nights kicked off on Saturday, February 4th, at Carol Ann Cross Park in Ft Smith. Eight more events are planned at the same location for the rest of 2006 through September. Our next "Stars in the Parks" public night is set for March 4th, and all public observing events begin at dusk.

ALL our events this year will be held on the FIRST SATURDAY of the month through September 2, EXCEPT for our last one which will be held on September 30. (That's TWO events in September!) Come join us to see what we can show you of our mysterious universe!

Visitors and members of AOAS view Saturn, the moon and much more at the kick-off of "Stars in the Parks" 2006 on February 4th. Member Richard Portman of Ft Smith adjusts his 8" Dobsonian telescope while viewing craters on the moon.

A new observing season has kicked off on February 4th at Carol Ann Cross Park in Ft Smith. Through our collaboration with the Ft Smith Parks Department's "Friends of the Parks" program, AOAS holds public observing nights at one of their facilities, and we receive use of one of their meeting rooms to hold our bi-monthly meetings. The collaboration works well for both entities and we enjoy the opportunity to hold several public nights each year at Carol Ann Cross Park.

Our February 4th event had eleven AOAS members with 8 telescopes set up for public viewing. The crowd was a little sparse, possibly due to the crisp air temperature, but the 25-30 people who DID join us were all well pleased with the views of Saturn, our moon, and a very small and distant planet Mars.

Click read more for the rest of this story; learn how to capture stellar objects with your digital camera
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Searching for the Invisible

NASA Space Placeby Diane K. Fisher

This giant dish antenna is about the size of a soccer field! It is part of NASA's Deep Space Network and is used to send and receive messages from its robotic space explorers.
Three blind flies land on an elephant. Each crawls over his part of the elephant and describes what he touches. The first one explores the trunk and says, "This creature is a wrinkled snake." The second one walks around on an ear and says, "This isn't a creature at all. It's a pancake." The third one hikes up and down the tail and says, "You are both crazy. This is nothing but a skinny rope hanging down from the sky."

If we are lucky enough to see the whole elephant at once, we understand how magnificent this animal really is.

So it is with astronomy. If we have only our poor eyes to look at the night, we see only a tiny part of the Universe. There is so much more to it than our eyes can see!

The light we see is but a tiny part of the light all around us. Therefore, humans have invented special telescopes that can see these different kinds of light. Using these new telescopes, both from the ground and from space, we have begun to see the entire elephant… er, Universe.

One kind of light we can't see is radio waves. We have learned to make our own radio waves for sending TV, radio, and cell phone signals through the air. Radio waves also come from stars (including our Sun), planets, clouds of gas in space, black holes, and other strange objects in space.

The telescopes that see radio waves don't look anything like the telescopes that see visible light. Radio telescopes are large dish-like antennas that can point to different parts of the sky. In addition to radio wave astronomy, NASA also uses this type of antennas—equipped with transmitters—to communicate with its unmanned spacecraft out there exploring the solar system.
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Whirlwind Disaster - Activity for Kids!

NASA Space PlaceWhere do these monster storms we call hurricanes come from? Why do they always form near the equator and only during certain times of the year? How do they come to be so organized and so destructive? You can find answers to these questions and play an exciting hurricane word game called "Whirlwind Disaster" at the SciJinks Weather Laboratory Web site. SciJinks targets young people of middle school age. It is a joint effort of the National Aeronautics and Space Administration (NASA) and the National Oceanic and Atmospheric Administration (NOAA). The new "How does a hurricane form?" page and accompanying interactive game can be found in the How & Why menu on the SciJinks Weather Laboratory home page, http://scijinks.gov.
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Green Bank Star Quest III

General NewsI received an e-mail From Devin Matlick of the NRAO at Green Bank West Virginia recently. The e-mail announced the upcoming Green Bank Star Quest III event, whic is a three-day event combining Radio and Visual Astronomy. This sounds very exciting and could be one of the better choices this year. Check out the details in our Events Calendar!
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Hayabusa - The Japanese Asteroid Sample Return Mission

Lunar & PlanetaryUPDATE: Japan's "Falcon" Wounded! Mission in Jeopardy!

Hayabusa (Japanese for Falcon) has encountered serious problems and the mission is in jeopardy. For an explanation of what the situation currently is, the Planetary Society article HERE is available for review.

A little known mission to return a sample of an asteroid to scientists on Earth has been underway for the past few years. Launched on May 9, 2003, the spacecraft's name is Hayabusa, and its mission is to rendezvous with asteroid Itokawa,

"Rubble-pile" Earth-Crossing Asteroid Itokawa.
land a very small robot craft named Minerva on its surface, scoop up a sample of asteroidal material, bring that back to Hayabusa, and eventually return it to Earth. Until the last two weeks, everything had gone pretty much as planned, but trouble now threatens to push back the return date for when the sample will be returned to Earth.

Asteroid Ida and its tiny moon Dactyl from the Galileo spacecraft's flyby in the early 1990's.
The Japan Aerospace Exploration Agency's (JAXA) Institute of Space and Astronautical Science (ISAS) spacecraft "Hayabusa" was launched on May 9, 2003 and arrived at its destination on September 12, 2005. Asteroid Itokawa has turned out to be what's known as a rubble-pile asteroid, an amalgam of rocks, rubble and dust held together by its miniscule mutual gravitational attraction. It just "looks" so much different from the other asteroids that we have images of, such as asteroid Ida below, instead of a large object with a solid looking surface spotted with anywhere from several dozen to several thousands of impact craters from other objects striking it. Itokawa is as rough as a cob with only a few spots of smooth surface area.

The smooth area seen in the image above is where the tiny (1 lb.) Minerva lander touched down for a sample of the asteroid's material for return to Earth.

While Hayabusa has been parked in orbit near Itokawa since September 12, the spacecraft has been experiencing some troubles in the past few weeks. Scientists all but lost contact with the craft 3 weeks ago, but are slowly regaining communications. The craft made its way to Itokawa by way of a newly developed Ion engine, and if the re-establishment of all communications and functions continues, the Ion engine will soon be re-ignited to allow Hayabusa to begin its return voyage to Earth. JAXA's website has all the latest information by clicking the Hayabusa info column here.

Click read more for the rest of this story.
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Stardust Spacecraft to Return January 15, 2006

Lunar & PlanetaryOn the evening of January 15, 2006, at about 4:00 am Arkansas time, a brilliant fireball will begin its passage over the Pacific NW on its way towards a landing in Utah. For people all over that area of the United States, the fireball will be a rare and wonderful site for about a minute. But for NASA scientists working on the Stardust mission, it will be "Welcome home, stranger" as the spacecraft's return module hits Earth's atmosphere at a higher speed than any other manmade object in history. It will be an anxious time until the little 100 lb. object slows itself enough to first release the drogue, and then the main parachutes, that will allow it to land unharmed in the Dugway Proving Grounds in the Utah desert.


UPDATE: Jan 1, 2006
Amateurs are asked to participate in watching, and recording, the re-entry of the Stardust return canister as it lights up the Pacific NorthWest. This following info comes from Night Sky Network.

Stardust Reentry Observing Opportunity and Call for Amateur Astronomer Participation

Stardust is the first U.S. space mission dedicated solely to the exploration of a comet, and the first robotic mission designed to return extraterrestrial material from outside the orbit of the Moon. Additionally, the Stardust spacecraft will bring back samples of interstellar dust, including recently discovered dust streaming into our Solar System from the direction of Sagittarius. Stardust is on its way back home, due to arrive as a visible "meteor" on January 15 starting at around 2 am PDT (3 am MDT). The "meteor" will be visible from several Western states, and especially good in Nevada and Utah. The capsule will actually make landfall in Utah, southwest of Salt Lake. The peak optical brightness is anticipated at minus 7.8. It will be hard to miss if you're in the right place.

Amateur astronomers are invited to participate in the mission! If you are interested in participating, the team is looking for video, still and even visual observation reports. If you are interested there is an observation form and list of observers here: http://reentry.arc.nasa.gov/registrationobserver.html
To learn more about participating in this event, go to the press release at: http://stardust.jpl.nasa.gov/science/feature002.html

The Stardust spacecraft is almost home now after a nearly 3 billion mile journey. Onboard are pristine samples of interstellar dust grains, and the first ever samples of particles returned from a comet.
NASA's Stardust spacecraft will have traveled some 2.89 billion miles by the time it returns its precious cargo to Earth on January 15, 2006. It successfully encountered periodic Comet 81P/Wild 2 (pronounced 'Vilt 2') in early January of 2004, when it opened its collector grid to allow microscopic particles of cometary dust to be captured in a special material known as Aerogel. This material is 99.8 percent air, and is some of the most highly efficient insulating material ever produced. Insulation is not its intended use, though, because it does an exceedingly good job at safely capturing and holding tiny particles only a few microns across which can impact at speeds of 10,000 mph or more.

Periodic Comet 81/P Wild 2
Stardust was the fourth of NASA's revolutionary missions designed to be cheaper, faster, better. The prime focus of the mission was to capture and return material from a comet, but it also used its unique aerogel material to capture unaltered interstellar dust grains from two different areas of its orbital path through the solar system. Scientists will be interested in finally knowing how unaltered interstellar dust grains compare to the micrometeorite particles that are collected regularly. These tiny objects, only a few microns in diameter, have experienced heating as they hit our atmosphere and are rapidly decelerated enough to eventually float down through the upper atmosphere to the ground.

But it is the cometary material that is of prime interest to NASA scientists, and especially to Dr. Donald Brownlee, principal investigator of the Stardust mission. Brownlee regularly studies the micrometeorites that are scooped up by ultra high-flying U-2 aircraft. These are part of the normal "daily delivery" of meteoritic material that enters the earth's atmosphere and gently rains down across the entire surface of the Earth. Believe it or not, we have all eaten meteoritic materials in the crops which are grown in the farm lands around the world. This material is in cabbage and lettuce and all other crops with large leaves, where the material falls onto the leaves and is then washed down by raindrops into the space between the leaves which is where it can be found when we eat the crop. Umm, tasty!

Click read more for the rest of this story.

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