Recent Geologic Activity on the Moon?

[/caption]
Recent images from NASA’s Lunar Reconnaissance Orbiter Camera provide evidence that the lunar crust may be pulling apart in certain areas. The images reveal small trenches less than a kilometer in length, and less than a few hundred meters wide. Only a small number of these features, known as graben, have been discovered on the lunar surface.

There are several clues in the high-resolution images that provide evidence for recent geologic activity on the Moon.

The LROC team detected signs of contraction on the lunar surface as early as August of 2010. The contractions were in the form of lobe-shaped ridges known as lobate scarps. Based on the data, the team suggests the widely-distributed scarps indicate the Moon shrank in diameter, and may be continuing to shrink. Interestingly enough, the new image data featuring graben presents a contradiction, as they indicate lunar crust being pulled apart and theorize that the process that created the graben may have occurred within the past 50 million years.

“We think the Moon is in a general state of global contraction due to cooling of a still hot interior, said thomas Watters from the Center for Earth and Planetary Studies. “The graben tell us that forces acting to shrink the Moon were overcome in places by forces acting to pull it apart. This means the contractional forces shrinking the Moon cannot be large, or the small graben might never form.”

Based on the size of the graben, the forces responsible for contraction of the lunar surface are assumed to be fairly weak. It is further theorized that, unlike the early terrestrial planets, the Moon was not completely molten during its early history.

“It was a big surprise when I spotted graben in the farside highlands,” said Mark Robinson, LROC Principal Investigator at Arizona State University. “I immediately targeted the area for high resolution stereo images so we could create a 3-dimensional view of the graben. It’s exciting when you discover something totally unexpected. Only about half the lunar surface has been imaged in high resolution. There is much more of the Moon to be explored.”

If you’d like to learn more about the recently discovered graben on the moon, you can watch a short video by Thomas Watters below:

To learn more about the Lunar Reconnaissance Orbiter Camera, visit: http://www.lroc.asu.edu/

Source: Arizona State University News

NASA Showcases ‘Spinoff’ Technologies

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Contrary to popular belief, Tang, Velcro and Teflon (along with the zero-gravity “space” pen) aren’t derived from NASA technology. NASA has, however, developed numerous technologies over the years, which are featured in annual “Spinoff” reports. Yes, “memory” foam mattresses are in fact one such product developed from NASA technologies.

NASA’s latest Spinoff edition features over forty of NASA’s most innovative technologies. The origins of each technology within NASA missions are provided, as well as their “spinoff” to the public as commercial products and/or technologies beneficial to society.

What new technologies have made their way this year from NASA labs and into our homes?

Generally, NASA spinoff technologies have proven useful in health and medicine, transportation, public safety, and consumer goods. Additional benefits from NASA spinoff technology can be found in the environment, information technology, and industrial productivity sectors. Experience has shown that these NASA technologies can help stimulate the economy and create new jobs and businesses in the private sector.

NASA Administrator Charles Bolden states, “This year’s Spinoff demonstrates once again how through productive and innovative partnerships, NASA’s aerospace research brings real returns to the American people in the form of tangible products, services and new jobs. For 35 years, Spinoff has been the definitive resource for those who want to learn how space exploration benefits life on Earth.”

A few highlights from NASA’s “Spinoff 2011” include:

  • A new firefighting system, influenced by a NASA-derived rocket design that extinguishes fires more quickly than traditional systems, saving lives and property.
  • Software employing NASA-invented tools to help commercial airlines fly shorter routes and help save millions of gallons of fuel each year, reducing costs to airlines while benefiting the environment.
  • A fitness monitoring technology developed with the help of NASA expertise that, when fitted in a strap or shirt, can be used to measure and record vital signs. The technology is now in use to monitor the health of professional athletes and members of the armed services.
  • An emergency response software tool that can capture, analyze and combine data into maps, charts and other information essential to disaster managers responding to events such as wildfires, floods or Earthquakes. This technology can save millions of dollars in losses from disasters and, more importantly, can help save lives when tragedy strikes.
  • The 2011 spinoff report also includes a special section celebrating commercial technologies derived from NASA’s Space Shuttle Program. Additionally, NASA lists spinoff technologies based on the construction of the International Space Station and work aboard the station. One other section in the report outlines potential benefits of NASA’s future technology investments.

    “NASA’s Office of the Chief Technologist has more than a thousand projects underway that will create new knowledge and capabilities, enabling NASA’s future missions,” NASA Chief Technologist Mason Peck adds. “As these investments mature, we can expect new, exciting spinoff technologies transferring from NASA to the marketplace, providing real returns on our investments in innovation.”

    If you’d like to learn more about NASA’s “Spinoff” program, visit: http://spinoff.nasa.gov/

    Curious about what NASA technologies affect your daily life? Visit: http://www.nasa.gov/city

    Source: NASA Spinoff Press Release

    Help Support a ‘New Horizons’ U.S. Postage Stamp!

    [/caption]Today the New Horizons mission team, along with Principal Investigator Alan Stern have unveiled their proposal for a U.S Postage stamp, to honor the first mission to Pluto.

    The current concept art for the stamp was done by Dan Durda, a space scientist and artist at The Southwest Research Institute. Durda’s work has appeared on the New Horizons website and in other locations. If the stamp is approved, it would be the successor to a U.S. postage stamp issued in 1990 that labeled Pluto as “Not Yet Explored.”

    “You can help make this happen.” says Stern.

    Since it can take several years for a proposed stamp to be approved by the U.S. post office, the mission team launched an internet petition today. The team plans to submit petitioners’ names along with their formal proposal, with the hopes that the stamp will be approved and printed in time to celebrate the New Horizons fly-by of Pluto in 2015.

    Stern added, “We’re asking people to sign the petition, because the post office considers not just the merits of a new stamp proposal, but also whether it is supported by a significant number of people. This is a chance for us all to celebrate what American space exploration can achieve though hard work, technical excellence, the spirit of scientific inquiry, and the uniquely human drive to explore.”

    Artist's impression of New Horizons' encounter with Pluto and Charon. Credit: NASA/Thierry Lombry
    You can help by signing the petition urging the post office’s Citizen Stamp Advisory Committee to recommend a New Horizons stamp to the postmaster general.

    The New Horizons team encourages people signing the petition to also tell their friends, family members, Facebook friends, Google plusketeers, and Twitter followers to sign as well!

    The text of the petition reads as follows:

    Greetings,

    I just signed the following petition addressed to: Citizens’ Stamp Advisory Committee.

    —————-
    The nation has an opportunity to honor a truly exemplary accomplishment of humankind in general, and the U.S. space program in particular, with a new U.S. postage stamp in 2015 honoring the flyby and reconnaissance of the Pluto system by NASA’s New Horizons spacecraft.

    New Horizons lifted off in January 2006 aboard a U.S. Atlas V rocket, the fastest spacecraft ever launched. In fact, New Horizons crossed the orbit of the Moon in just nine hours – almost 10 times quicker than the Apollo lunar missions. Since then, New Horizons has been speeding toward Pluto – more than three billion miles from Earth — covering nearly one million miles a day!

    New Horizons will make its closest approach to Pluto and its family of moons on July 14, 2015, 50 years to the day after Mariner 4 made the first successful flyby of Mars.

    With the New Horizons flyby of Pluto, the U.S. space program will complete the first era of planetary reconnaissance, a profoundly inspiring feat of lasting historical significance. Moreover, the Pluto flyby will represent the first exploration of the Kuiper Belt, the first exploration of a double planet, the first exploration of an ice dwarf planet, and the farthest object ever explored in space.

    Join the mission team in asking the U.S. Postal Service to commemorate the historic achievements of New Horizons by signing this petition in support of a new postage stamp, supplanting the 1990 U.S. stamp that described Pluto simply as “Not Yet Explored.”

    The petition urges the Citizen Stamp Advisory Committee to recommend to the Postmaster General a stamp in honor of New Horizons.

    Let’s celebrate what humans can achieve though hard work, technical excellence, scientific inquiry and the uniquely human spirit of exploration.
    —————-

    Sincerely,

    [Your name]

    Sign the petition at: http://www.change.org/petitions/usps-honor-new-horizons-and-the-exploration-of-pluto-with-a-usps-stamp

    If you’d like to learn more about the New Horizons mission, visit: http://pluto.jhuapl.edu/index.php

    Source: New Horizons Mission Updates

    Test Your Knowledge and Skills with NASA’s New Online Games

    [/caption]This week, NASA has launched its first multi-player online game on Facebook to test players’ knowledge of the space program, as well as an interactive air traffic control mobile game for iPad, iPhone, and iPod touch.

    The first game, Space Race Blastoff asks players questions such as “Who was the first American to walk in space?” and “Who launched the first liquid-fueled rocket?”

    Sector 33 is the second game, which puts the player in the role of a lead air traffic controller. The players task is to guide air traffic safely through “Sector 33” as quickly as possible. To achieve their goal, players must choose the most efficient route and make strategic speed changes.

    Are you up for the challenges NASA has put forth in Space Race Blastoff and Sector 33 ?

    Space Race Blastoff tests players’ knowledge of NASA history, technology, science and pop culture. When players answer correctly, they earn in-game “badges” which depict NASA astronauts, spacecraft and celestial objects. Points are also awarded for correct answers, and players can redeem the points to obtain more badges, including “premium” badges.

    Space Race Blastoff character select screen. Image credit: NASA
    The game play experience is fairly straight forward: Players choose their avatar and then answer 10 multiple-choice questions. Correct answers earn the player 100 points. The first player to answer correctly earns a 20-point bonus. The winner of the round advances to a bonus round where they can earn additional points and a badge.

    “Space Race Blastoff opens NASA’s history and research to a wide new audience of people accustomed to using social media,” said David Weaver, NASA’s associate administrator for communications. “Space experts and novices will learn new things about how exploration continues to impact our world.”

    While NASA is emphasizing the “multi-player” aspect of the game by making the game available through Facebook, players can also opt to play solo games.

    Sector 33 screenshot. Image Credit: NASA
    Ever wonder what it’s really like to work as an Air Traffic Controller?

    Put yourself in this scenario:

    It’s a stormy night in Northern California as air traffic is quickly approaching the San Francisco Bay Area from the East. You are in charge of Sector 33 which all flights must pass through.

    Can you handle the job of guiding planes safely through Sector 33 as quickly as possible?

    Sector 33 is designed to be an interactive game to interest students in aeronautics-related careers and connect mathematics and problem solving to the real world.

    Some additional features of Sector 33 are:

  • 35 problems featuring two to five airplanes
  • Speed and route controls
  • Weather obstacles
  • Four levels of controller certification
  • In-game introduction, hints, and help section
  • Extra videos
  • Moonbase Alpha screenshot. Image credit: NASA
    You can play Space Race Blastoff at: http://apps.facebook.com/spacerace

    Download the Sector 33 App for free for the iPad, iPhone, and iPod touch through the App store

    For those of you a bit more “hard-core” about your gaming, NASA continues to offer their “Moonbase Alpha” demo via STEAM.

    How Well Can Astronomers Study Exoplanet Atmospheres?

    [/caption]

    Exoplanet discoveries are happening at a frenetic pace, and some of the latest newly discovered worlds are sometimes described as “Earth-Like” and “potentially habitable.”

    The basis of this comparison is, in many cases, based on the distance between the exoplanet and its host star. Unfortunately the distance between a planet and its host star is only half the picture. The other half is determining if an exoplanet has an atmosphere, and what the contents of said atmosphere may be.

    Basically, just because an exoplanet is in the “habitable zone” around its host star, it may not necessarily be habitable. If an exoplanet has a thick, crushing, Venus-Like atmosphere, it would most likely be too hot for surface water. The opposite holds true as well, as it could be entirely possible for an exoplanet to have a thin, wispy Mars-like atmosphere where any water would be locked up as ice.

    At this point, how well can astronomers study the atmosphere around an exoplanet?

    The spectrum from a giant exoplanet, orbiting around the bright, young, star HR 8799. Image Credit: ESO/M. Janson
    Currently, there are only a handful of methods researchers can use to make estimates of exoplanet atmospheres. Interestingly enough, one method makes use of the light coming from the host star. The basic principle is that the light from a star can be analyzed both before and after an exoplanet crosses in front of the star. By comparing the spectrum from the host star, and the spectrum of an exoplanet, the tell-tale signs of atmospheric contents can be detected.

    Methods to detect the atmospheric composition of such distant worlds are fairly new, as shown by work done with the Spitzer Space Telescope and ESO’s Very Large Telescope

    Recently, astronomers from The Sternberg Astronomical Institute at Moscow State University used data from the Hubble Space Telescope in an attempt to better detect atmospheres around exoplanets. Abubekerov and team created mathematical models to analyze light curves from distant stars. In the case of Abubekerov’s research, the selected star was HD 189733 – a K-class star a bit cooler and smaller than our Sun.

    About 60 light-years from Earth, HD 189733 also happens to have a binary companion orbiting it at a radius of about 200 A.U. So far, one exoplanet is known to orbit HD 189733. Discovered in 2005, HD 189733 b is a roughly Jupiter-size exoplanet which orbits its host star in just over two days. While not mentioned directly in Abubekerov’s paper, other studies have detected methane, carbon monoxide, water vapor and sodium in HD 189733 b’s atmosphere.

    Light curve from HD 189733 in 5500 - 6000 angstrom range.
    By applying their models to the light curves from HD 189733, Abubekerov’s team was able to better understand how light at different wavelengths behaves when an exoplanet crosses in front of its host star.

    According to Abubekerov and team, the end result of their research was unsuccessful. The team suspects dark spot activity on HD 189733 was a contributing factor to their models not agreeing with actual observations.

    The team stressed that additional observational data from HD 189733 when spot activity is negligible would be required to further refine their work. Despite their models not being successful, the team is confident that exoplanet radius increases with decreasing wavelength, which may imply the presence of an atmosphere.

    Research such as Abubekerov’s will help astronomers build better models and pave the way for “sniffing” exoplanet atmospheres. Newer technology such as the James Webb Space Telescope and the European Extremely Large Telescope will also provide better data. In the not-too-distant future, astronomers and astrobiologists should be able to examine the atmospheres of exoplanets in the habitable zone.

    If you’d like to read the full research paper, you can access a pre-print version at: http://arxiv.org/pdf/1201.4043v1.pdf

    Source(s): Analysis of Light Curves of Eclipsing Systems with Exoplanets:
    HD 189733. M. K. Abubekerov, N. Yu. Gostev, and A. M. Cherepashchuk
    , Extrasolar Planets Encyclopaedia

    Citizen Science: GLOBE at Night

    [/caption]Are you a fan of Citizen Science? Do you enjoy participating in projects that help researchers and possibly the environment?

    GLOBE at Night is one such program! By taking naked-eye observations of the night sky in your area, you can help a world-wide effort to track the effects of light pollution.

    Here’s all the info you need in order to participate in GLOBE at Night during 2012.

    For starters, what is GLOBE at Night?

    The GLOBE at Night program is an international citizen-science campaign designed to raise public awareness of the impact of light pollution on our night skies. GLOBE at Night aims to raise awareness by inviting citizen-scientists to measure their night sky brightness and submit their observations to a website from a computer or smart phone.

    Light pollution not only threatens our “right to starlight”, but also affects energy consumption, wildlife and health. For the past six years, the GLOBE at Night campaign has been involving people in 115 countries.

    Participating in GLOBE at Night requires only five easy steps:

    1) Find your latitude and longitude.

    2) Find Orion, Leo or Crux by going outside more than an hour after sunset (about 8-10pm local time).

    3) Match your nighttime sky to one of the provided magnitude charts.

    4) Report your observation.

    5) Compare your observation to thousands around the world.

    Map of 2011 GLOBE at Night participation. Image Credit: GLOBE at Night / NOAO

    You can also use the new web application data submission process. The GLOBE at Night website is easy to use, comprehensive and holds an abundance of background information. The database is usable for comparisons with a variety of other databases, like how light pollution affects the foraging habits of bats.

    If you’d like to learn more about GLOBE at Night, visit: http://www.globeatnight.org/ , or the 365 Days of Astronomy Podcast: GLOBE at Night Kickoff: Seeing the Light.

    Could a ‘Death Star’ Really Destroy a Planet?

    [/caption]Countless Sci-Fi fans vividly remember the famous scene in Star Wars in which the Death Star obliterates the planet Alderaan.

    Mirroring many late night caffeine-fueled arguments among Sci-Fi fans, a University of Leicester researcher asks the question:

    Could a small moon-sized battle station generate enough energy to destroy an Earth-sized planet?

    A paper by David Boulderston (University of Leicester) sets out to answer that very question. First, for the uninitiated, just what the heck is a Death Star?

    According to Star Wars lore, the DS-1 Orbital Battle Station, or Death Star, is a moon-sized battle station designed to spread fear throughout the galaxy. The image above shows the Death Star as it appeared in Star Wars Episode IV: A New Hope (1977). The Death Star’s main weapon is depicted as a superlaser capable of destroying planets with a single blast.

    Boulderston claims that it is possible to estimate how much energy the Death Star would need in order to destroy a planet with its superlaser. There are a number of assumptions made, however, in order to come up with the energy requirement.

    For starters, Boulderston assumed that Alderaan did not have any sort of planetary “deflector” shield. A second assumption is that the planet is a solid body of uniform density – essentially ignoring the complex interior of planets, due to lack of information on Alderaan itself. Using the idealized sphere model based on Earth’s mass and diameter, it was possible to determine the gravitational binding energy of Alderaan, using a simple equation of:

    U= 3GMp2
    ——
    5Rp

    Where G is the Gravitational Constant (6.673×10-11), Mp is planet mass, and Rp is the planet’s radius. Using Earth’s mass and radius, the required energy comes out to 2.25 x 1032 Joules. Using Jupiter’s data, the energy required goes up to 2 x 1036 Joules.

    Boulderston asserts that (according to Star Wars lore) the Death Star is powered by a ‘hypermatter’ reactor, possessing the energy output of several main-sequence stars. Given that the power output of our Sun is about 3 x 1026 Joules per second, it’s a reasonable assumption the Death Star’s reactor could power the superlaser.

    Despite using a simplified model of a planet, Boulderstone states the simplified model is reasonable to use since the Death Star’s main power reactor has the energy output equal to several main-sequence stars. Even if Earth’s exact composition were used in the equation above, the required energy to destroy a planet would only be affected by a few orders of magnitude – well within the Death Star’s power budget.

    Boulderstone reiterated that the energy required to destroy a Jupiter-sized planet would put considerable strain on the Death Star. To destroy a planet like Jupiter, all power from essential systems and life support (no re-routing from the auxiliary EPS conduits – that’s a Star Trek hack!) would be required, which is not necessarily possible.

    Boulderstone’s conclusion is that the Death Star could indeed destroy Earth-like planets, given its main power source. While the Death Star could destroy an Earth-sized planet, a Jupiter-sized planet would be a tough challenge, and the Galactic Empire would need to resort to using a Suncrusher to destroy stars.

    If you’d like to read Boulderstone’s paper, you can access it at: https://physics.le.ac.uk/journals/index.php/pst/article/view/328/195

    Does Starburst Activity Starve Galaxies of Gas?

    [/caption]Using the partially constructed ALMA observatory, a group of astronomers have found new evidence that helps explain how young, star-forming galaxies end up as ‘red and dead’ elliptical galaxies.

    According to current galactic evolution theories, mergers of spiral galaxies are thought to explain why nearby elliptical galaxies have few young stars. Merging galaxies direct gas and dust into starburts, which are regions of rapid star formation, as well as into the central supermassive black hole at the core of the merging galaxies. As matter is piled onto a black hole, powerful jets erupt, and the region becomes a brightly shining quasar. Eventually the powerful jets emanating from the central black hole push away any potentially star-forming gas, which causes the starbursts to cease.


    Astronomers have, until recently, been unable to detect enough mergers at the “jet” stage to make a definite link between the outflows and the end of starburst activity. During early science observations in 2011, ALMA became the first telescope to confirm almost two dozen galaxies at the critical, yet brief stage of galaxy evolution.

    “Despite ALMA’s great sensitiviy to detecting starbursts, we saw nothing, or next to nothing – which is exactly what we hoped it would see,” said Dr. Carol Lonsdale (NRAO). Lonsdale presented the findings at the American Astronomical Society’s meeting in Austin, Texas on behalf of an international team of astronomers.

    ALMA was set to look for the signature of dust warmed by star-forming regions. Half of Lonsdale’s two dozen galaxies were not visible in ALMA’s observations, and the other half very dim.

    “ALMA’s results reveal to us that there is little-to-no starbursting going on in these young, active galaxies. The galaxy evolution model says this is thanks to their central black holes whose jets are starving them of star-forming gas,” Lonsdale said. “On its first run out of the gate, ALMA confirmed a critical phase in the timeline of galaxy evolution.”

    Infographic showing the sequence of events that model a typical galaxy becoming a so-called "red and dead" elliptical. Lonsdale and her team found a large population of galaxies, right in the middle of this sequence, between steps d and e. Image Credit: Hopkins, et al., NOAO/AURA/NSF.

    After the star-forming gas is blown away, merging galaxies no longer form new stars. Once the massive, bright, blue, and short-lived stars die out, the redder, longer-lived, lower mass stars begin to dominate the population, leading to a gas-starved galaxy taking on a redder hue. To support the gas-starvation theory, astronomers needed to observe the process at work, specifically in merging galaxies with high power jets where quasars can be found.

    Lonsdale added, “The missing phase had to be among quasars that could be seen brightly in infrared and radio wavelengths — mergers young enough to have their cores still swaddled in infrared-bright dust, but old enough that their black holes were well fed and producing jets observable in the radio.”

    The team’s hunt for the specific type of quasars began with NASA’s Wide-field Infrared Survey Explorer (WISE) spacecraft. The WISE data consists of millions of objects in its all-sky survey of the Universe. Lonsdale led WISE’s quasar survey team that picked out the brightest, reddest objects this infrared telescope had mapped.

    Selected images from among the twenty-three quasars observed with ALMA so far in its hunt for candidate starving galaxies. Image Credit: C. Lonsdale, NRAO/AUI/NSF; ALMA (NRAO/ESO/NAOJ)

    Lonsdale and her team compared the WISE data against the NRAO’s VLA Sky Survey of 1.8 million radio objects. The team then used results common to both sets of data to determine the best targets for their starburst search with ALMA. Since ALMA uses longer infrared wavelengths than WISE, Lonsdale’s team was able to make the distinction between dust warmed by starburst activity and dust heated by material falling onto the central black hole.

    There are 26 more WISE quasars for ALMA to survey before Lonsdale and her team publish their results. In the meantime, Lonsdale and her team will observe these galaxies with the newly re-named Karl G. Jansky Very Large Array (VLA).

    “ALMA revealed to us this rare stage of galaxy starvation, and now we want to use the VLA to focus on delineating the outflows that robbed these galaxies of their fuel,” Lonsdale said. “Together, the two most sensitive radio telescope arrays in the world will help us truly understand the fate of spiral galaxies like our own Milky Way.”

    If you’d like to learn more about the Atacama Large Millimeter/Submillimeter Array (ALMA), visit: https://almascience.nrao.edu/about-alma/alma-site

    Source: NRAO Press Release

    Mike Fossum Answers Your Questions

    [/caption]We recently launched a new “Ask” feature here at Universe Today. Our inaugural launch featured Dr. Alan Stern, Principal Investigator for the New Horizons mission to Pluto and the Kuiper Belt.

    Following up on the success of our first “Ask” feature, we’ve followed up with a new installment featuring Expedition 29 commander Mike Fossum. We collected your questions and passed them along to Mike who graciously took the time to answer them.

    Here are the questions picked by you, the readers, and Fossum’s responses. Special thanks to NASA and Mike Fossum for their participation.

    1.) Living on the ISS is sometimes said to be a difficult experience – if you could make any one change to the ISS to make it more comfortable, what would it be?

    Mike Fossum: “Get the transporter working – it would be great to be home for the weekend.” Fossum also added, “I loved living and working there (The ISS) and there’s very few things I’d change. I had a great window view and my own personal quarters. I guess if anything I missed being able to sit in a chair – that and being able to have a cup of coffee (instead of out of a bag) and read the newspaper in the morning.”

    2.) As a trained astronaut, what are your thoughts on the feasibility of making space flight a routine for normal civilians ( besides tourists) especially with regard to interplanetary/beyond earth orbit flights?

    Mike Fossum: “I think we’ll see low Earth-orbit very soon.” Fossum also mentioned, “I was born a few months after Sputnik’s launch, the changes in spaceflight over the past 54 years are staggering. The potential for changes over the next fifty years is unimaginable.” Fossum also had a parting thought on the rise of commercial space travel, “I have a nagging voice telling me to say “be careful”, we’ve learned hard and costly lessons”.

    3.) While in the Earth’s shadow, could you see the stars, constellations and planets? If you could, did they look any better or brighter?

    Mike Fossum: “Oh, Yes! The key is to be in a place where you can dark adapt – any sunlight overpowers night vision.” Fossum mentioned that during some “down” time on a spacewalk, he was able to turn off his helmet lights and immerse himself in the “3-d feeling” of being in the stars. Describing the quality of the views, Fossum stated, “The Milky Way was clear, and no twinkle in stars. The different colors of stars were more intense”.

    4.) After a typical stay on the ISS, how long does it take an astronaut to recover from the effects of weightlessness?

    Mike Fossum: “There’s a great deal of recovery in the first three weeks. Balance, running, walking, I’d say I’m at about 90%” Fossum mentioned one other side effect of his stay on the ISS – apparently he’s in better physical shape than before he left. Fossum speculated that the improvements in his physical shape were due to the rigorous exercise routines he performed during his stay on the ISS.

    5.) What would you say is the strongest asset that each of the space fairing countries brings to the table when it comes to our forward progress into space as a species?

    Mike Fossum: “The Russians have a different design process than we (The United States) do. They evolve, rather than start over.” Fossum added, “Looking at their station module design, they took stuff that worked from MIR and improved upon it, they analyzed and tested and broke stuff and added more steel. Americans analyze and analyze – it was a real shock to NASA on how Russia built things.” Fossum mentioned that in 2008, he helped install the JAXA Kibo module on the International Space Station and was impressed by the efficiency of JAXA engineers.

    Regarding some of the other partner nations participating in the ISS, Fossum mentioned, “ESA has the best of German efficiency and Italian flexibility.” Fossum also discussed the Canadians niche in robotics, stating that they’ve been leaders who are proud of their work. Fossum cited the success of the remote manipulator arm on the space shuttles, as well as the “big arm” on the ISS and the DEXTRE manipulator.

    Fossum shared a final thought regarding all the nations participating in the ISS, stating, “There’s a common passion for space among the big partners on the ISS.” Fossum also mentioned to “Look at history” regarding Russia, Germany, Italy, Japan and the U.S, emphasizing that nations who were at war with each other not that long ago are working together to achieve common goals in space.

    This wraps up our latest “Ask” feature. Once again we’d like to thank Mike Fossum and NASA for taking the time to answer your questions.

    Wandering Stars Shed Light on Milky Way’s Past

    [/caption]Like a worldly backpacker, many stars in the Milky Way Galaxy have made interesting journeys, and have interesting stories to tell about their past. For over a decade, the Sloan Digital Sky Survey (SDSS) has been mapping stars in our Galaxy.

    This week at the American Astronomical Society meeting in Austin, Texas, astronomers from University of California – Santa Cruz presented new evidence that claims to answer many questions about stars located in the disk of our galaxy. The team’s results are based on data from the Sloan Extension for Galactic Understanding and Exploration 2 (SEGUE-2).

    The SEGUE-2 data is comprised of the motions and chemical compositions of over 118,000 stars, most of which are in the disk of our galaxy, but a few stars in the survey take the “scenic” route in their orbit.

    “Some disk stars have orbits that take them far above and below the plane of the Milky Way,” said Connie Rockosi (University of California – Santa Cruz), “We want to understand what kinds of stars those are, where they came from, and how they got there.”

    Aside from the orbital paths of these “wandering” stars being different from most other Milky Way stars, their chemical composition also makes them unique. A team led by Judy Cheng (University of California – Santa Cruz) studied the metallicity of stars at different locations in the galaxy. By studying the metallicity, Cheng and her team were able to examine how the disk of the Milky Way disk grew over time. Cheng’s study also showed that stars closer to the center of the galaxy have higher metallicity than those farther from the galactic center. “That tells us that the outer disk of our Galaxy has formed fewer generations of stars than the inner disk, meaning that the Milky Way disk grew from the inside out,” added Cheng.

    When Cheng studied the “wandering” stars, she found their metallicity doesn’t follow the same trend – no matter where she looked in the target area of the Galaxy, stars had low metal content. “The fact that the metal content of those stars is the same everywhere is a new piece of evidence that can help us figure out how they got to be so far away from the plane,” Rockosi mentioned.

    What the team has yet to determine is if the stars formed with their “wandering” orbits, or if something in the past caused them to migrate to their unique paths. “If these stars were born with these orbits, they were born at the same rate all over the galaxy,” Cheng said. “If they were born with regular orbits, then whatever happened to them must have been very efficient at mixing them up and erasing any patterns in the metal content, such as the inside-out trend we see in the plane.”

    Some possible reasons for this mixing include past mergers of our Galaxy and others, or possibly spiral arms sweeping through the disk. Cheng’s observations will help determine what causes stars to wander far from their birthplace. Other galaxies have shown stars in their disks as well, so solving the puzzle presented by these stars will help researchers better understand how spiral galaxies like the Milky Way form.

    If you’d like to read Cheng and Rockosi’s paper “Metallicity Gradients In The Milky Way Disk As Observed By The SEGUE Survey”, you can download a copy at: http://www.ucolick.org/~jyc/gradient/cheng_apj_fullres.pdf

    Source: UC Santa Cruz press release