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Wednesday, October 17 2018 @ 09:03 am EDT

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Goodbye, Old Friend: Hubble Mission May End

General NewsThe White House under George W. Bush has announced that the Hubble Space Telescope will be allowed to die a sooner-than-expected fiery death. The announcement has been made that the planned robotic servicing mission scheduled for 2006 will be scrapped due to its estimated overall cost of some $1 billion. Without a servicing mission Hubble will fall back to Earth in the next few years.

The venerable Hubble Space Telescope has earned its place in history many times over. But perhaps more importantly, it has earned a place in the hearts of the American public. Hubble is our telescope, bought and paid for with American tax dollars, and loved as no science instrument has ever been loved. The American people should have some say in whether this decision shall be the final word for the gallant Hubble. The National Aeronautics and Space Administration is, after all, funded by the American taxpayer. They, work for you.

News of this decision has been greeted with deep concern by scientists. Quoting Holland Ford, an astronomer for John Hopkins University in a story by Robert Roy Britt of Space.Com, “I sure hope it’s wrong….[this] means that a lot of excellent science that could be done will not be done.” Britt spoke with Ford by telephone Friday, January 21. “It will be a great loss for science. It will also be a great loss for the way in which Hubble communicates science through [it’s] images to people around the world,” Ford added. In the same Space.com article, the American Astronomical Society’s deputy executive director, Kevin Marvel, stated that rumors of Hubble’s demise had been circulating for several days. Thousands of astronomers represented by the American Astronomical Society, “[will] work to try and make sure that some sort of servicing [mission] is made available for Hubble,” said Marvel in his telephone interview with Britt.

Click "read more" for the rest of this story.
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AURORA WATCH: AURORAS MAY STILL BE POSSIBLE JANUARY 18 THRU 20

SolarA - STRONG - Coronal Mass Ejection (CME) has been detected and reportedly headed towards Earth. Power companies and airlines have been warned again of strong auroral and solar storm activity from January 16 through January 20.

UPDATE: SECOND CME POSSIBLY STRONGER

UPDATE 2: THEY KEEP COMING!! A *3rd* and possibly the strongest yet CME has been observed bringing even more solar particles towards Earth. There have also been 3 extremely powerful solar flares associated with each of these CME's. The sunspot region below (Region 10720) is also capable of producing even more events until it passes beyond the western solar limb in 4-5 days.The SOHO link below will show the current position of region 10720, and auroras are still possible through early morning hours of January 20.


Watch for auroras in the northern parts of Arkansas and Oklahoma from tonight through the morning of Thursday January 20th. The chances are still HIGH that an aurora WILL be visible any of these dates. TWO CME's have been detected and now a 3rd with even more significant amounts of solar particles still headed towards Earth. There are NO dangerous effects from these CME's, but they are responsible for the occasional auroras we see in mid-latitude regions of the world as well as electrical grid disruptions.

Anyone may attempt to capture this auroral activity with any camera which can be set to "manual" and which will accept a cable release. Use 400 speed film or faster...camera on a tripod w/cable release...expose for 15 seconds up to 1-2 minutes with shorter times for brighter portions of an aurora (15-45 sec)...watch for yellow or orange bands extending upwards which MAY show some "curtain" effect I.E. waving as if in a breeze.


See "A Solar Connection to the Aurora of November 7, 2004"

Watch for any "skyglow" on the northern horizon as if there were a LARGE city just beyond your view. This will appear as a greenish-white band near the northern horizon. Watch for any reddish-orangish or yellowish "glow" blending with the upper fringes of this greenish horizonal "glow". DRESS WARMLY to be able to watch as long as possible.

Auroral activity comes in "waves", meaning that the activity can change dramatically over a very short period of time. What might not be more than a greenish glow at the northern horizon can suddenly flare up to reveal huge areas of reddish to orangish color, and may on rare occasions turn bright green or blue. The activity is expected to be fairly high during this event through Thursday Jan 20, with the best activity Tuesday, Wednesday and/or Thursday nights.

This event is expected to reach as far south as the mid-US, but there is at least a 50-50 chance of an aurora.

Clarification: Moonlight this evening MAY hinder the intensity of any visible auroral activity. Likewise, observers from within city limits may also see little if any auroral activity. If viewing from within city limits, try and find a shadowed area away from most street lights. Better views will be had after moonset around 2:30am Tuesday and around 4:45 am Thursday.

For more on the Solar activity that spawned this activity, go to:http://sohowww.nascom.nasa.gov/

For information on auroral activity and solar flares, go to:http://www.spacew.com/

Solar image from Solar and Heliospheric Observatory (SOHO) MIDI Continuum image from January 16.

Aurora image by AOAS astrophotographer Mike Holloway of the Aurora of Nov 7, 2004 from north of Van Buren.

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Huygens Base – A Successful Landing on another World

The world today marvels at the first ever images of the surface of Saturn’s largest moon, Titan. Bigger than the planets Mercury or Pluto, Titan has long been known to have a very thick atmosphere composed of organic compounds and deadly gases. With the January 14, 2005 landing of the Huygens probe on the surface of Titan, mankind will have only just begun to scratch the surface of the secrets this mysterious world holds.

The Huygens probe rode piggyback aboard the Cassini spacecraft for seven long years until it was released to drift on its own towards Titan on Christmas Eve, 2004. The probe was gently pushed and spun simultaneously away from Cassini to provide more stability for that moment when it would enter the outer layers of Titan’s atmosphere in the early morning hours (local time) of January 14, 2005. A huge radio telescope at Greenbank, West Virginia picked up a faint signal from the compact-car-sized probe at around 4:37AM announcing the successful emergence of the probe's transmission antenna. This antenna could only have been extended if the heat shield and parachute system were working properly, thereby indicating that the mission had begun as planned.

As the probe continued down through the nearly 100-mile-thick atmosphere, two more parachutes would be deployed at specific times and altitudes to allow Huygens to “sniff”, “feel”, “hear” and “see” what the composition of Titan’s atmosphere actually was. All of the instruments operated as planned except for one data relay channel, and at around 7:00AM local time the probe touched down on Titan as planned.

The Cassini spacecraft pointed itself towards the surface of Titan to pick up the weak signals from Huygens, and then relayed those signals back to NASA’s Deep Space Network, a system of large radio telescopes stationed around the Earth to allow nearly continuous reception of data from the Huygens and Cassini team. After the 1hr 7minute trip from Titan at the speed of light, the radio transmissions were relayed from the DSN to the European Space Agency’s control facilities at Darmstadt, Germany. The raw images were processed only slightly and were then quickly released to a waiting world of scientists and curious onlookers eager to see for themselves what the surface of this forbidding world looked like. The defective data channel resulted in only 350 images being returned instead of 700 that could have been returned, but these images still give a most intriguing look at the hidden surface of Titan.
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Stardust Up Close

NASA Space Placeby Patrick L. Barry and Dr. Tony Phillips

The Stardust spacecraft used a grid holding aerogel to capture dust particles from comet Wild 2. In this test, high velocity dust particles are stopped unharmed at the end of cone shaped tracks in a sample of aerogel.
Like discarded lumber and broken bricks around a construction site, comets scattered at the edge of our solar system are left-over bits from the "construction" of our solar system.

Studying comets, then, can help scientists understand how our solar system formed, and how it gave rise to a life-bearing planet like Earth.

But comets have long been frustratingly out of reach -- until recently. In January 2004 NASA's Stardust probe made a fly-by of the comet Wild 2 (pronounced "vilt"). This fly-by captured some of the best images and data on comets yet ... and the most surprising.

Scientists had thought that comets were basically "rubble piles" of ice and dust -- leftover "construction materials" held together by the comet's feeble gravity. But that's not what Stardust found. Photos of Wild 2 reveal a bizarre landscape of odd-shaped craters, tall cliffs, and overhangs. The comet looks like an alien world in miniature, not construction debris. To support these shapes against the pull of gravity, the comet must have a different consistency than scientists thought:

"Now we think the comet's surface might have a texture like freeze-dried ice cream, so-called 'astronaut ice cream': It's solid and can assume odd, gravity-defying shapes, but it's basically soft and crumbles easily," says Donald Brownlee of the University of Washington, principal investigator for Stardust.

Scientists are currently assembling a 3-D computer model of this surface from the photos that Stardust took. Those photos show the sunlit side of the comet from many angles, so its 3-dimensional shape can be inferred by analyzing the images. The result will be a "virtual comet" that scientists can examine from any angle. They can even perform a virtual fly-by. Using this 3-D model to study the comet's shape in detail, the scientists will learn a lot about the material from which the comet is made: how strong or dense or brittle it is, for example.
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Antennas, Designed by Darwin

NASA Space Placeby Patrick L. Barry

Enlarge Photo
Who in their right mind would design this bizarre-looking antenna? Actually, nobody did. It evolved.

Taking a cue from nature, NASA engineers used a kind of "artificial evolution" to find this design. The result may look odd, but it works very well.

"The evolutionary process improves the design of antennas, just as evolution in nature leads to fitter plants and animals," says Jason Lohn, leader of the Evolvable Systems Group at NASA's Ames Research Center.

The improvement comes from Darwin's idea of natural selection: only the fittest members of a generation survive to produce offspring. Over many generations, traits that hinder survival are weeded out, while beneficial traits become more common. "In the end," he says, "you have the design equivalent of a shark, honed over countless generations to be well adapted to its environment and tasks."

Evolutionary computation, as it's called, applies this principle to hardware design. It's particularly useful for tackling problems that are difficult to solve by hand--like the design of new antennas.

Designing a new antenna for NASA's Space Technology 5 (ST-5) mission was the challenge facing Lohn's group. ST-5 will explore how TV-sized "nano-satellites" can perform the tasks of much larger, conventional satellites at a cheaper cost. Antennas on these satellites must be smaller than usual, yet capable of doing everything that a bigger antenna can do.

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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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Near-Earth Asteroid 2004 MN4 Reaches Highest Score To Date On Hazard Scale

Lunar & PlanetaryDon Yeomans, Steve Chesley and Paul Chodas
NASA's Near Earth Object Program Office
December 23, 2004


A recently rediscovered 400-meter Near-Earth Asteroid (NEA) is predicted to pass near the Earth on 13 April 2029. The flyby distance is uncertain and an Earth impact cannot yet be ruled out. The odds of impact, presently around 1 in 300, are unusual enough to merit special monitoring by astronomers, but should not be of public concern. These odds are likely to change on a day-to-day basis as new data are received. In all likelihood, the possibility of impact will eventually be eliminated as the asteroid continues to be tracked by astronomers around the world.
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Awaiting the Huygens Probe Landing on Titan

European Space Agency releases the first image of Titan's surface on January 14, 2005. This image reveals "stubby channels running through an apparent shoreline into a "sea" or "lake" on the surface". Image was taken at an altitude of some 10 miles. (ESA Photo)
The Cassini/Huygens spacecraft will arguably begin the most significant portion of its long mission to the Ring World this Friday, Christmas Eve. The world will watch as the European Space Agency's Huygens probe will separate from the NASA Cassini mothership to begin a fall that will end with the touchdown of Huygens on the surface of Saturn's largest moon Titan on January 14th.

UPDATE 1: 12.25.04 Huygens has been successfully released and is on its way, alone, towards Titan.

UPDATE 2: TOUCHDOWN ON TITAN THIS MORNING, JAN 14TH! The Huygens probe will begin its journey into the outer layers of Titan's atmosphere at approximately 4:20 AM. The journey will take nearly 3 hours before the probe reaches the surface. The MORNING NEWS SHOWS should be carrying this event, and possibly carrying it LIVE!

"BONNE CHANCE", HUYGENS!!!

UPDATE 3: From the Robert C. Byrd Radio Telescope in Green Bank, West Virginia. "The 'carrier signal' has been detected and Huygens has entered the atmosphere of Titan, 11:37 Central European Time (4:37am CST)" !!!

SUCCESS! HUYGENS PROBE LANDS SAFELY; SENDS A "SCIENTIFIC BOUNTY OF INFORMATION"!!!

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Galactic Surprise

NASA Space Placeby Patrick L. Barry and Dr. Tony Phillips

M81 is 10 million light years away. The image on the left was made from GALEX data and shows UV light from hot, new stars. These star forming regions are not detectable in the visible light image on the right (McGraw-Hill Observatory, Kitt Peak, Arizona, Greg Bothum, Univ. of Oregon.)
Open an old astronomy textbook. The basic sketch you'll find there of galaxy formation is fairly simple: a vast cloud of diffuse hydrogen and helium gas condenses under gravity, and dense spots in the cloud collapse to form stars. Voila! A galaxy.

But real galaxies are much more complex than that. A galaxy is a swirling "soup" of billions of stars and roaming black holes, scattered clouds of gas and dust, random flashes of star birth and exploding supernovas, and an unseen and mysterious substance called "dark matter." Over time, all these ingredients mix and interact—pulling and compressing and colliding—and somehow that interplay leads to the galaxies we see today. No wonder it's such a hard problem to solve!

Just over one year into its three-year mission, GALEX is already shedding some new light on the problem.

"Some of the discoveries GALEX has made will change our understanding of how galaxies develop and when, where, and why stars form in galaxies," says Peter Friedman, a researcher at Caltech and Project Scientist for GALEX.

This small space telescope, called the Galaxy Evolution Explorer (GALEX for short), makes its discoveries by taking pictures of millions of galaxies scattered over the whole sky. Some of these galaxies are close by (at least by astronomical standards of "close"), while others are as much as 10 billion light-years away. Because light takes time to travel through space, we see these distant galaxies as they appeared billions of years ago. Comparing young galaxies from the distant past with older, modern galaxies will teach scientists about how galaxies change over time.
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A Solar Connection to the Aurora of November 7, 2004

The colorful aurora of Sunday, November 7, 2004, was widely seen in the Ft Smith/Van Buren area. Here are some current pictures of our Sun and the sunspot group responsible for this latest dance of "Fire in the Sky".

The colorful red and green aurora that lit up the skies over northwestern Arkansas last Sunday evening was caused by a huge blast of energized particles originating from the Sun a few days before. These high energy particles are produced by our Sun and exhaled in a sort of cosmic hiccup that sends the particles screaming away from the Sun in whatever direction the area that produced those particles happened to be facing when the exhalation occurred. This time, the area on the Sun which produced this aurora was pointed directly at Earth.

Aurorae are not uncommon. Energized particles from the Sun are streaming away from the solar surface all the time. The Earth's magnet field that protects us from harmful cosmic radiation, also acts to funnel the normal flow of solar material from our Sun and concentrate it into our atmosphere near the north and south polar regions. Hence the more widely known terms "Aurora Borealis", or Northern Lights, and "Aurora Australis", or Southern Lights. Thousands of people flock to areas of the world at high northerly or southerly latitudes on cruise ships or by air travel to places like Anchorage, Alaska, specifically to see these awesomely beautiful curtains of colorful light in the sky.

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