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Saturday, September 23 2017 @ 03:33 am EDT

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Universe is actually stranger than fiction

General News
Galactic center of the Milky Way from the Spitzer Space Telescope. Photo courtesy NASA/JPL

Science fiction, that is. Scientists revealed last week that there are more strange things in the universe than most had supposed even as recently as five years ago. At last week's annual meeting of U.S. astronomers, research findings were announced that described such oddities as “rogue” black holes that wander the Milky Way galaxy.

As mentioned in an Associated Press article on the Earthlink News website,  scientists describe “baby blue dwarfs” and a giant glob of “dark matter” in a supercluster of galaxies, with forces so great that they have had to invent a new vocabulary to describe the kind of violent behavior associated with these cramped-together galaxies. They refer to such terms as “slow strangulation” and “stripping” as events that unfold when these galaxies collide.

Other phenomena include a massive gas cloud 1 million times as massive as the Sun that is rushing toward the Milky Way at a high rate of speed. of course, since it is 47 quadrillion miles away, the collision with our galaxy won't happen for a another 40 million years.

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Ultraviolet Surprise

NASA Space Placeby Patrick L. Barry and Tony Phillips

Astronomers looking at new ultraviolet images from the Galaxy Evolution Explorer spacecraft were surprised to discover a 13-light-year long tail on Mira, a star that has been extensively studied for 400 years.
How would you like to visit a universe full of exotic stars and weird galaxies the likes of which astronomers on Earth have never seen before?

Now you can. Just point your web browser to galex.stsci.edu and start exploring.

That's the address of the Galaxy Evolution Explorer image archive, a survey of the whole sky at ultraviolet wavelengths that can't be seen from the ground. Earth's atmosphere blocks far-ultraviolet light, so the only way to see the ultraviolet sky is by using a space telescope such as NASA's Galaxy Evolution Explorer.

About 65% of the images from the all-sky survey haven't been closely examined by astronomers yet, so there are plenty of surprises waiting to be uncovered.

“The Galaxy Evolution Explorer produces so much data that, beyond basic quality control, we just don't have time to look at it all,” says Mark Seibert, an astronomy postdoc at the Observatories of the Carnegie Institution of Washington in Pasadena, California.

This fresh view of the sky has already revealed striking and unexpected features of familiar celestial objects. Mira is a good example. Occasionally visible to the naked eye, Mira is a pulsating star monitored carefully by astronomers for more than 400 years. Yet until Galaxy Evolution Explorer recently examined Mira, no one would have guessed its secret: Mira possesses a comet-like tail 13 light-years long.

“Mira shows us that even well-observed stars can surprise us if we look at them in a different way and at different frequencies,” Seibert says.

Another example: In April, scientists announced that galaxies such as NGC 1512 have giant ultraviolet spiral arms extending three times farther out into space than the arms that can be seen by visible-light telescopes. It would be like looking at your pet dog through an ultraviolet telescope and discovering his ears are really three times longer than you thought!

The images from the ultraviolet space telescope are ideal for hunting new phenomena. The telescope's small, 20-inch primary mirror (not much bigger than a typical backyard telescope) offers a wide field of view. Each image covers 1.2 degrees of sky — lots of territory for the unexpected.

If someone combing the archives does find something of interest, Seibert advises that she or he should first search astronomy journals to see whether the phenomenon has been observed before. If it hasn't, email a member of the Galaxy Evolution Explorer science team and let them know, Seibert says.

So what are you waiting for? Fire up your web browser and let the discoveries begin!

This article was provided by the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration.
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Going My Way?

NASA Space Placeby Diane K. Fisher

NASA's New Millennium Program selects breakthrough technologies that will be of the greatest use to future space and Earth science missions and that are perceived to be risky to the first user.
Not many endeavors require that you plan the mode of transportation before you even know what it is you are transporting. But weighing the physics and economics of getting any sort of cargo to space is a major part of designing a space mission.

It's one of the first issues that NASA's New Millennium Program (NMP) considers when planning a new mission. NMP has the forward-looking job to identify promising new technologies for space exploration. It then helps to mature the technology so it will be available to space missions of the future. If the technology cannot be tested adequately on Earth, the last part of this process is to actually send the technology into space. With carefully documented test results, future mission planners can confidently incorporate the new technology into their designs.

But where to begin? On call from the start, Linda Herrell is the New Millennium Program Architect. Given a list of proposed technologies, she has the job of figuring out the feasibility of wrapping a mission around them.

“We might be considering six or more technologies, anything from solar panels to imagers to masts for solar sails to more intelligent software. Of those, we may choose four. My job is to answer the question — can the selected technology be transported to and operated in space within the constraints of a low-cost technology validation project?”

Along with the list of possible mission payloads (the technologies), Linda also has a list of spacecraft to put them on, as well as a list of launch vehicle parameters. All she has to do is try them out in every possible combination (of which there are thousands) and see what might work.

“Fortunately, we have a software tool to help with this analysis,” says Linda. When it comes down to it, her job is primarily to figure out how to get the technologies into space.

“Sometimes, it's like figuring out how to get across town when you don't have your own car. You have to get creative.”

She keeps a database of all possible options, including riding piggyback on another spacecraft, hitching a ride on a launch vehicle as a secondary payload, or sharing a launch vehicle with other NASA, Department of Defense, or even commercial payloads.

Her assessment is but one of a gazillion factors to be considered in planning a mission, but it is indeed one of the very first “details” that forms the foundation for the rest of the mission.

Find out some of the technologies that NMP has already validated or is considering at nmp.nasa.gov/TECHNOLOGY/innovative-tech.html. Kids will enjoy watching Linda's cartoon alter-ego talk about her job at spaceplace.nasa.gov/en/kids/live .

This article was provided by the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration.
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Earth Impact Craters

Lunar & Planetary
Barringer Meteor Crater, Arizona, USA
When we look at Earth's Moon, as well as NASA photos of Mars, Mercury, the moons of the outer planets, and asteroids such as Eros, the most obvious surface features are impact craters.

From our backyards, even with the smallest of optics, we can readily observe many thousands of craters on the Moon's surface. These craters range from the size of city blocks to several hundred miles in diameter. The age of the Moon has been estimated to be approximately 4 billion years, based on the lunar samples brought back by the Apollo astronauts. Throughout the lunar life span the Moon has been a cosmic target by millions of rocks and pieces of ice — from a size smaller than a grain of sand to asteroids many miles in diameter.

But has the Earth been hit? Of course, the answer is YES.

It's well known that there is a constant fall of debris entering the atmosphere of our planet every day, with most particles as fine as dust, but some are as large as a basketball. From time to time, larger chunks enter our atmosphere and are large enough to survive the plunge. These actually strike the surface of the Earth.

Recently, one such meteorite made worldwide news, after it struck in northern South America. Luckily, there were no casualties, and the damage was limited to a small crater. There are almost monthly reports of meteorites, fire balls, or bolides. A bolide is a bright meteor that usually burns up in the atmosphere, but on rare occasions, they do strike the Earth's surface.
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The Red (Hot?) Planet

NASA Space Placeby Patrick L. Barry

Just as changing cloud patterns on Earth were identified using Earth Observing-1's Advanced Land Imager along with ScienceCraft software, the THEMIS instrument with ScienceCraft on the Mars Odyssey spacecraft can avoid transmitting useless images.
Click image for larger view.
Don't let Mars's cold, quiet demeanor fool you. For much of its history, the Red Planet has been a fiery world.

Dozens of volcanoes that dot the planet's surface stand as monuments to the eruptions that once reddened Mars's skies with plumes of glowing lava. But the planet has settled down in its old age, and these volcanoes have been dormant for hundreds of millions of years.

Or have they? Some evidence indicates that lava may have flowed on Mars much more recently. Images of the Martian surface taken by orbiting probes show regions of solidified lava with surprisingly few impact craters, suggesting that the volcanic rock is perhaps only a million years old.

If so, could molten lava still occasionally flow on the surface of Mars today?

With the help of some artificial intelligence software, a heat-sensing instrument currently orbiting Mars aboard NASA's Mars Odyssey spacecraft could be just the tool for finding active lava flows.

"Discovering such flows would be a phenomenally exciting scientific finding," says Steve Chien, supervisor of the Artificial Intelligence Group at JPL. For example, volcanic activity could provide a source of heat, thus making it more likely that Martian microbes might be living in the frosty soil.

The instrument, called THEMIS (for Thermal Emission Imaging System), can "see" the heat emissions of the Martian surface in high resolution — each pixel in a THEMIS image represents only 100 meters on the ground. But THEMIS produces about five times more data than it can transmit back to Earth.

Scientists usually know ahead of time which THEMIS data they want to keep, but they can't plan ahead for unexpected events like lava flows. So Chien and his colleagues are customizing artificial intelligence software called ScienceCraft to empower THEMIS to identify important data on its own.

This decision-making ability of the ScienceCraft software was first tested in Earth orbit aboard a satellite called Earth Observing-1 by NASA's New Millennium Program. Earth Observing-1 had already completed its primary mission, and the ScienceCraft experiment was part of the New Millennium Program’s Space Technology 6 mission.

On Odyssey, ScienceCraft will look for anomalous hotspots on the cold, night side of Mars and flag that data as important. "Then the satellite can look at it more closely on the next orbit," Chien explains.

Finding lava is considered a long shot, but since THEMIS is on all the time, "it makes sense to look," Chien says. Or better yet, have ScienceCraft look for you — it’s the intelligent thing to do.

To learn more about the Autonomous ScienceCraft software and see an animation of how it works, visit http://ase.jpl.nasa.gov.

This article was provided by the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration.
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A Missile in Your Eye

NASA Space Place
This three-color composite image from the computed tomographic imaging spectrometer shows the oxygenation of the blood in the arteries and veins of a human retina. (Arteries appear red, veins appear yellow.)
Click image for larger view.
Satellite technology designed to catch ballistic missile launches may soon help doctors monitor the health of people's eyes.

For the last 15 years, Greg Bearman and his colleagues at JPL have been working on a novel design for a spectrometer, a special kind of camera often used on satellites and spacecraft. Rather than snapping a simple picture, spectrometers measure the spectrum of wavelengths in the light coming from a scene. From that information, scientists can learn things about the physical properties of objects in the photo, be they stars or distant planets or vegetation on Earth's surface.

In this case, however, the challenge was to capture snapshots of short-lived events — like missile launches! The team of JPL scientists designed the new spectrometer, called a computed tomographic imaging spectrometer (CTIS), in collaboration with the Ballistic Missile Defense Organization as a way to detect missiles by the spectral signatures of their exhaust.

But now the scientists are pointing CTIS at another fast-moving scene: the retina of an eye.

Blood flowing through the retina has a different spectral signature when it is rich in oxygen than when it is oxygen deprived. So eye doctors can use a spectrometer to look for low oxygen in the retina — an indicator of disease. However, because the eye is constantly moving, images produced by conventional spectrometers would have motion blurring that is difficult to correct.

The spectrometer that Bearman helped to develop is different: It can capture the whole retina and its spectral information in a single snapshot as quick as 3 milliseconds. “We needed something fast,” says Bearman, and this spectrometer is “missile-quick.”

CTIS is even relatively cheap to build, consisting of standard camera lenses and a custom, etched, transparent sheet called a grating. “With the exception of the grating, we bought everything on Amazon,“ he says.

The grating was custom-designed at JPL. It has a pattern of microscopic steps on its surface that split incoming light into 25 separate images arranged in a 5 by 5 grid. The center image in the grid shows the scene undistorted, but colors in the surrounding images are slightly “smeared” apart, as if the light had passed through a prism. This separation of colors reveals the light's spectrum for each pixel in the image.

”We're conducting clinical trials now,” says Bearman. If all goes well, anti-missile technology may soon be catching eye problems before they have a chance to get off the ground.

Information about other NASA-developed technologies with spin-off applications can be found at http://www.sti.nasa.gov/tto .

This article was provided by the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration.
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Cosmic Cockroaches

NASA Space PlaceBy Dr. Tony Phillips

Using the IR spectrometer on the Spitzer Space Telescope, scientists found organic molecules in supernova remnant N132D.
Click image for larger view.
Cockroaches are supposed to be tough, able to survive anything from a good stomping to a nuclear blast. But roaches are wimps compared to a little molecule that has recently caught the eye of biologists and astronomers — the polycyclic aromatic hydrocarbon.

Polycyclic aromatic hydrocarbons (PAHs for short) are ring-shaped molecules made of carbon and hydrogen. “They're all around us,” says Achim Tappe of the Harvard Center for Astrophysics. “PAHs are present in mineral oils, coal, tar, tobacco smoke and automobile exhaust.” Aromatic, ring-shaped molecules structurally akin to PAHs are found in DNA itself!

That's why Tappe's recent discovery may be so important. “PAHs are so tough, they can survive a supernova.”

The story begins a few thousand years ago when a massive star in the Large Magellanic Cloud exploded, blasting nearby star systems and interstellar clouds with hot gas and deadly radiation. The expanding shell, still visible from Earth after all these years and catalogued by astronomers as “N132D,” spans 80 light years and has swept up some 600 Suns worth of mass.

Last year “we observed N132D using NASA's Spitzer Space Telescope,” says Tappe. Spitzer is an infrared (IR) telescope, and it has a spectrometer onboard sensitive to the IR emissions of PAHs. One look at N132D revealed “PAHs all around the supernova's expanding shell. They appear to be swept up by a shock wave of 8 million degree gas. This is causing some damage to the molecules, but many of the PAHs are surviving.”

Astronomers have long known that PAHs are abundant not only on Earth but throughout the cosmos — they've been found in comet dust, meteorites and many cold interstellar clouds—but who knew they were so tough? “This is our first evidence that PAHs can withstand a supernova blast,” he says.

Their ability to survive may be key to life on Earth. Many astronomers are convinced that a supernova exploded in our corner of the galaxy 4-to-5 billion years ago just as the solar system was coalescing from primitive interstellar gas. In one scenario of life's origins, PAHs survived and made their way to our planet. It turns out that stacks of PAHs can form in water — think primordial seas — and provide a scaffold for nucleic acids with architectural properties akin to RNA and DNA. PAHs may be just tough enough for genesis.

Cockroaches, eat your hearts out.

Find out about other Spitzer discoveries at www.spitzer.caltech.edu.

This article was provided by the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration.
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Safe Green Laser Pointer Usage

General NewsBy Leonard Lynch

In the past, there has been a lot of discussion in the news regarding green laser pointers. They are a great tool for amateur astronomers, however, there is great concern by the government that a terrorist might attempt to cause an aircraft to crash by spotting one with a laser. This seemed ridiculous to me for a number of reasons, but because laser pointers are so commonly used by the amateur astronomy community, I wanted to understand the facts better before I purchased one. The following is what I found:

The laser pointers commonly used by amateur astronomers are green, continuous wave lasers emitting light centered at 532nm wavelength. They are required by the FDA to have a warning or danger sticker on them that indicates the class of the device, which in turn depends on the maximum output of the device. The FDA regulates the devices because of their potential to cause eye injury. Most amateur laser pointers are either Class II (output <= 1mW) or Class IIIA (output <= 5mW) devices. Even though the industry is required to label their products as described, random tests have shown that some devices exceed their labeled output. Accordingly, studies described below apply to correct output levels.

The FDA has studied and published reports on laser exposure to the human eye and associated injury. These studies show that tissue damage may occur when the eye is exposed to a Class IIIA 5mW green laser at a distance of 10 feet or less. This fact alone should cause astronomers to understand how carefully these lasers should be handled. Even though eye tissue damage is a serious matter, it is not the critical issue with the FAA. Instead, they are concerned with glare, flash-blindness and after-images when an aircrew is exposed to laser light. The FAA has studied how much exposure affects aircrew and the degree to which exposure can be tolerated in relation to where the aircraft is in its takeoff or approach pattern.
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Omit Needless Bytes!

NASA Space Placeby Patrick Barry and Tony Phillips

This artist's concept shows the New Horizons spacecraft during its planned encounter with Pluto and its moon, Charon. The spacecraft is currently using the Beacon Monitor system on its way to Pluto. Credit: Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute (JHUAPL/SwRI)
Click image for larger view.
Now is an exciting time for space enthusiasts. In the history of the Space Age, there have never been so many missions “out there” at once. NASA has, for example, robots on Mars, satellites orbiting Mars, a spacecraft circling Saturn, probes en route to Pluto and Mercury — and four spacecraft, the two Voyagers and the two Pioneers, are exiting the solar system altogether.

It's wonderful, but it is also creating a challenge.

The Deep Space Network that NASA uses to communicate with distant probes is becoming overtaxed. Status reports and data transmissions are coming in from all over the solar system — and there's only so much time to listen. Expanding the network would be expensive, so it would be nice if these probes could learn to communicate with greater brevity. But how?

Solving problems like this is why NASA created the New Millennium Program (NMP). The goal of NMP is to flight-test experimental hardware and software for future space missions. In 1998, for instance, NMP launched an experimental spacecraft called Deep Space 1 that carried a suite of new technologies, including a new kind of communication system known as Beacon Monitor.

The system leverages the fact that for most of a probe's long voyage to a distant planet or asteroid or comet, it's not doing very much. There's little to report. During that time, mission scientists usually only need to know whether the spacecraft is in good health.

“If you don't need to transmit a full data stream, if you only need some basic state information, then you can use a much simpler transmission system,” notes Henry Hotz, an engineer at NASA's Jet Propulsion Laboratory who worked on Beacon Monitor for Deep Space 1. So instead of beaming back complete data about the spacecraft's operation, Beacon Monitor uses sophisticated software in the probe's onboard computer to boil that data down to a single “diagnosis.” It then uses a low-power antenna to transmit that diagnosis as one of four simple radio tones, signifying “all clear,” “need some attention whenever you can,” “need attention soon,” or “I'm in big trouble — need attention right now!”

“These simple tones are much easier to detect from Earth than complex data streams, so the mission needs far less of the network's valuable time and bandwidth,” says Hotz. After being tested on Deep Space 1, Beacon Monitor was approved for the New Horizons mission, currently on its way to Pluto, beaming back a simple beacon as it goes.

Discover more about Beacon Monitor technology, as well as other technologies, on the NMP Technology Validation Reports page, http://nmp-techval-reports.jpl.nasa.gov.

This article was provided by the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration.
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And the WINNER IS - MELANTHA SPRAYBERRY

General NewsWe have pulled the winning ticket for our Telescope Raffle, and the winner is, Melantha Sprayberry and family of Van Buren, AR. I made the call to her just one minute after the ticket was drawn by Entertainment Fort Smith editor Tessa Freeman who graciously agreed to be our official "ticket picker" for the evening. Now, we'll go about teaching the Sprayberry family all we can about how to use their new 6" telescope,
Melantha and husband John Sprayberry of Van Buren pose with their brand new 6" telescope on their porch on Friday, July 13th. What a lucky Friday the 13th it's been for them!
and how to use it to find up to a few thousand of the nicer objects in this neighborhood of our Milky Way galaxy.


I took the 6" Celestron StarHopper Dobsonian-style reflector directly to them in Van Buren immediately after the drawing was completed. Upon meeting them I saw a great deal of excitement about winning this telescope, and about the FREE 1st year membership in AOAS as well. We setup their telescope on their front porch and viewed Venus first, and then I finally spotted a very low Saturn and they were able to see the Ring World as well before it dropped behind some trees. It was love at first site, I believe.

These two young folks are going to be very interested students of astronomy. I also feel like they'll fit right in with our other club members.
Tessa Freeman, Calendar Editor for Entertainment Fort Smith graciously accepted our request to be our official "ticket picker" for the drawing on the 6" telescope. Here she and I pose for an unofficially official picture.
I asked Melantha when and where they had bought their ticket, and she said they had bought it at our first big event at the Old Timer's Day Festival in downtown Van Buren on May 12th. And, just to make this win a little bit sweeter, they bought only the one single ticket for $5, making this a win with just slightly lower odds of winning considering how many folks paid the $20 for 5 tickets. This was certainly one Friday the 13th they won't soon forget.

John and Melantha have a daughter who is visiting with relatives this summer, but they told me how much she was going to love getting this new telescope. After I heard them describe this young girl and how excited she had acted when we gave her some copies of the little booklets we were giving out at the Old Timer's event. That's when I remembered them as they were standing at our booth in May, asking all kinds of questions. Its funny how I now recall that I hoped they'd be the winner even though I knew it'd be a pure stroke of luck if they did. Come to think of it, I hoped quite a few people would be the winner. Our efforts at selling raffle tickets brought us into contact with a LOT of nice people who were very interested in astronomy and in our club.

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