An image gallery gift from NASA's Swift

Dec. 28, 2012 — Of the three telescopes carried by NASA's Swift satellite, only one captures cosmic light at energies similar to those seen by the human eye. Although small by the standards of ground-based observatories, Swift's Ultraviolet/Optical Telescope (UVOT) plays a critical role in rapidly pinpointing the locations of gamma-ray bursts (GRBs), the brightest explosions in the cosmos.

But as the proxy to the human eye aboard Swift, the UVOT takes some amazing pictures. The Swift team is celebrating eight years of UVOT operations by collecting more than 100 of the instrument's best snapshots in a web-based photo gallery (http://www.swift.psu.edu/uvot/coolPics.php). The images also can be viewed with the free Swift Explorer Mission iPhone app (https://itunes.apple.com/us/app/swift-explorer/id465669299?mt=8) developed by the Swift Mission Operations Center (MOC), which is located in State College, Pa., and operated by Penn State.

Swift has detected an average of about 90 GRBs a year since its launch in 2004. "When we aren't studying GRBs, we use the satellite's unique capabilities to engage in other scientific investigations, some of which produce beautiful images from the UVOT that we're delighted to be able to share with the public," said Michael Siegel, the lead scientist on the UVOT and a research associate in astronomy and astrophysics at the MOC.

The targets range from comets and star clusters to supernova remnants, nearby galaxies and active galaxies powered by supermassive black holes.

"One of our more challenging projects in the past was completing an ultraviolet mosaic of M31, the famous Andromeda galaxy," said Stefan Immler, a member of the Swift team at NASA's Goddard Space Flight Center in Greenbelt, Md. "Because the galaxy is so much larger than the UVOT field of view, we had to take dozens of pictures and blend them together to show the whole object."

An ongoing mosaic project targets the Large and Small Magellanic Clouds, two small satellite galaxies orbiting our own, and makes the Andromeda effort look like child's play. Although the galaxies are much smaller than M31, they are both much closer to us and extend over much larger areas of the sky. The task involves acquiring and aligning hundreds of images and is far from complete.

With the UVOT's wavelength range of 1,700 to 6,000 angstroms, Swift remains one of few missions that study ultraviolet light, much of which is blocked by Earth's atmosphere.

The 6.5-foot-long (2 meter) UVOT is centered on an 11.8-inch (30 cm) primary mirror. Designed and built by the Mullard Space Science Laboratory in Surrey, England, the telescope module includes the primary and secondary mirrors, an external baffle to reduce scattered light, two redundant detectors -- only one has been used to date -- and a power supply.

Each detector lies behind an identical filter wheel. The wheel holds color filters that transmit a broad range of wavelengths as well as devices called grisms, which spread out incoming light in much the same way as a prism spreads sunlight into a rainbow of component colors. The detectors retain information on the position and arrival time of each photon of light, an operating mode similar to typical X-ray telescopes.

Because most ultraviolet light never reaches the ground, Swift's UVOT provides a unique perspective on the cosmos. For example, it can measure the amount of water produced in passing comets by detecting the ultraviolet emission of hydroxyl (OH), one of the molecular fragments created when ultraviolet sunlight breaks up water molecules. Other types of UVOT science include exploring emissions from the centers of active galaxies, studying regions undergoing star formation, and identifying some of the rarest and most exotic stars known.

Toward the end of its energy-producing life, a star like the sun will blow away its outer layers as its core transforms into a compact, Earth-sized remnant known as a white dwarf. This chapter of stellar evolution, known to astronomers as the post-asymptotic giant branch phase, lasts only about 100,000 years -- just an eye-blink in comparison to the star's total lifetime. To better understand the process, astronomers need to study large numbers of these unusual stars.

"The UVOT's capabilities give us a great tool for surveying stellar populations and cataloging rare types of ultraviolet-bright stars," Siegel explained.

One of the first targets for the stellar survey was the giant cluster Omega Centauri, which hosts millions of stars and may be the remains of a small galaxy. Thanks to Swift's UVOT, astronomers at Goddard and Penn State have cataloged hundreds of rare stellar types in the cluster and are now comparing their properties and numbers to predictions from theoretical models describing how stars evolve.

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Clays on Mars: More plentiful than expected

Dec. 20, 2012 — A new study co-authored by the Georgia Institute of Technology indicates that clay minerals, rocks that usually form when water is present for long periods of time, cover a larger portion of Mars than previously thought. In fact, Assistant Professor James Wray and the research team say clays were in some of the rocks studied by Opportunity when it landed at Eagle crater in 2004. The rover only detected acidic sulfates and has since driven about 22 miles to Endeavour Crater, an area of the planet Wray pinpointed for clays in 2009.

The study is published online in the current edition of Geophysical Research Letters.

The project, which was led by Eldar Noe Dobrea of the Planetary Science Institute, identified the clay minerals using a spectroscopic analysis from the Mars Reconnaissance Orbiter. The research shows that clays also exist in the Meridiani plains that Opportunity rolled over as it trekked toward its current position.

"It's not a surprise that Opportunity didn't find clays while exploring," said Wray, a faculty member in the School of Earth and Atmospheric Sciences. "We didn't know they existed on Mars until after the rover arrived. Opportunity doesn't have the same tools that have proven so effective for detecting clays from orbit."

The clay signatures near Eagle crater are very weak, especially compared to those along the rim and inside Endeavour crater. Wray believes clays could have been more plentiful in the past, but Mars' volcanic, acidic history has probably eliminated some of them.

"It was also surprising to find clays in geologically younger terrain than the sulfates," said Dobrea. Current theories of Martian geological history suggest that clays, a product of aqueous alteration, actually formed early on when the planet's waters were more alkaline. As the water acidified due to volcanism, the dominant alteration mineralogy became sulfates. "This forces us to rethink our current hypotheses of the history of water on Mars," he added.

Even though Opportunity has reached an area believed to contain rich clay deposits, the odds are still stacked against it. Opportunity was supposed to survive for only three months. It's still going strong nine years later, but the rover's two mineralogical instruments don't work anymore. Instead, Opportunity must take pictures of rocks with its panoramic camera and analyze targets with a spectrometer to try and determine the composition of rock layers.

"So far, we've only been able to identify areas of clay deposits from orbit," said Wray. "If Opportunity can find a sample and give us a closer look, we should be able to determine how the rock was formed, such as in a deep lake, shallow pond or volcanic system."

As for the other rover on the other side of Mars, Curiosity's instruments are better equipped to search for signs of past or current conditions for habitable life, thanks in part to Opportunity. Wray is a member of Curiosity's science team.

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Journal Reference:

E. Z. Noe Dobrea, J. J. Wray, F. J. Calef, T. J. Parker, S. L. Murchie. Hydrated minerals on Endeavour Crater's rim and interior, and surrounding plains: New insights from CRISM data. Geophysical Research Letters, 2012; 39 (23) DOI: 10.1029/2012GL053180

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NASA puts Orion backup parachutes to the test

Dec. 20, 2012 — NASA completed the latest in a series of parachute tests for its Orion spacecraft Thursday at the U.S. Army Yuma Proving Ground in southwestern Arizona, marking another step toward a first flight test in 2014. The test verified Orion can land safely even if one of its two drogue parachutes does not open during descent.

Orion will take humans farther into space than ever before, but one of the most challenging things the multipurpose vehicle will do is bring its crew home safely. Because it will return from greater distances, Orion will reenter Earth's atmosphere at speeds of more than 20,000 mph. After re-entry, the parachutes are all that will lower the capsule carrying astronauts back to Earth.

"The mockup vehicle landed safely in the desert and everything went as planned," said Chris Johnson, a NASA project manager for Orion's parachute assembly system. "We designed the parachute system so nothing will go wrong, but plan and test as though something will so we can make sure Orion is the safest vehicle ever to take humans to space."

Orion uses five parachutes. Three are main parachutes measuring 116 feet wide and two are drogue parachutes measuring 23 feet wide. The 21,000-pound capsule needs only two main parachutes and one drogue. The extra two provide a backup in case one of the primary parachutes fails.

To verify Orion could land safely with only one drogue parachute, engineers dropped a spacecraft mockup from a plane 25,000 feet above the Arizona desert and simulated a failure of one of the drogues. About 30 seconds into the mockup's fall, the second drogue parachute opened and slowed the mockup down enough for the three main parachutes to take over the descent.

The next Orion parachute test is scheduled for February and will simulate a failure of one of the three main parachutes.

In 2014, an uncrewed Orion spacecraft will launch from Cape Canaveral Air Force Station in Florida on Exploration Flight Test-1. The spacecraft will travel 3,600 miles above Earth's surface. This is 15 times farther than the International Space Station's orbit and farther than any spacecraft designed to carry humans has gone in more than 40 years. The main flight objective is to test Orion's heat shield performance at speeds generated during a return from deep space.

For information about Orion, visit: http://www.nasa.gov/orion

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Canadian experiment to track space radiation and its risks

Dec. 20, 2012 — Space can be a potentially hazardous environment to live and work in, especially when it comes to radiation. Originating from violent storms on the Sun and galactic cosmic rays produced in distant supernovae explosions, this natural radiation can pose a serious health risk for astronauts on long-duration space missions like those on the International Space Station (ISS).

Like a protective bubble, Earth's atmosphere and magnetosphere shields life on our planet from this never-ending bombardment of high-energy particles. However, in low-Earth orbit where the International Space Station (ISS) flies, astronauts are regularly exposed to high doses of radiation, including charged particles trapped in Earth's magnetic field, as well as cosmic rays and solar radiation.

To prepare for future missions that may last for months or years, the Canadian Space Agency (CSA), along with other space agencies around the world, have been stepping up research into radiation biology in recent years, recognizing that it deserves the highest priority.

During CSA astronaut Chris Hadfield's mission to the ISS, he will carry a new set of instruments into orbit to measure one of the most serious types of radiation -- caused by high-energy neutron particles -- and monitor the dose an astronaut absorbs during space flight.

What is Neutron Radiation?

Neutron radiation is considered to be one of the most severe of all types of radiation experienced in space as it can cause biological damage. It represents approximately 30% of the total exposure for those aboard the ISS. In space, neutrons are produced when charged particles collide with physical matter, such as the walls and equipment on the ISS. Just like medical X-rays, these high-energy particles can shoot through delicate body tissues, and through long-term exposure, they can damage DNA and potentially cause cataracts, bone marrow damage or even cancer.

It's all in the bubbles -- Bubbles and Radiation Trouble

Radi-N2 is Canada's second generation of neutron radiation monitoring aboard the ISS and continues on where fellow Canadian astronaut Robert Thirsk and the original Radi-N experiment left off in 2009.

A collaborative effort between the CSA and Russia's RSC-Energia and State Research Center of Russia Institute of Biomedical Problems (IBMP) Russian Academy of Sciences, the Radi-N2 study will have Chris Hadfield and fellow crewmember Roman Romanenko measure the neutron radiation levels on the station while onboard the ISS for Expedition 34/35.

Radi-N2 uses bubble detectors produced by a Canadian company, Bubble Technology IndustriesExternal link, Opens in a new window of Chalk River, Ontario, designed to focus on detecting neutrons while ignoring other types of radiation. Bubble detectors have been used in space for more than two decades on space shuttle missions and the MIR space station, and have become popular because of their accuracy and convenience.

Eight of these finger-sized instruments are going to be placed by Hadfield and Romanenko around various ISS modules. Each detector is filled with a clear polymer gel, inside which are liquid droplets. When a neutron strikes the test tube, a droplet may be vaporized. This creates a visible gas bubble in the polymer. Each bubble, which represents neutron radiation, is then placed within an automatic reader and counted.

Radi-N2 will provide critical information for potential future human missions to the moon, asteroids and eventually Mars.

The CSA's support of radiation research will not only lead to major advancements for future human exploration of space but also in our knowledge of the health risks of radiation, such as cancer, neurological damage and degenerative tissue disease.

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Saturn mission: Cassini instrument learns new tricks

Dec. 20, 2012 — For seven years, a mini-fridge-sized instrument aboard NASA's Cassini spacecraft reliably investigated weather patterns swirling around Saturn; the hydrocarbon composition of the surface of Saturn's moon Titan; the aerosol layers of Titan's haze; and dirt mixing with ice in Saturn's rings. But this year the instrument -- the visual and infrared mapping spectrometer (VIMS) -- has been testing out some new telescopic muscles.

This Friday, Dec. 21, the spectrometer will be tracking the path of Venus across the face of the sun from its perch in the Saturn system. Earthlings saw such a transit earlier this year, from June 5 to 6. But the observation in December will be the first time a spacecraft has tracked a transit of a planet in our solar system from beyond Earth orbit.

Cassini will collect data on the molecules in Venus's atmosphere as sunlight shines through it. But learning about Venus actually isn't the point of the observation. Scientists actually want to use the occasion to test the VIMS instrument's capacity for observing planets outside our solar system.

"Interest in infrared investigations of extrasolar planets has exploded in the years since Cassini launched, so we had no idea at the time that we'd ask VIMS to learn this new kind of trick," said Phil Nicholson, the VIMS team member based at Cornell University, Ithaca, N.Y., who is overseeing the transit observations. "But VIMS has worked so well at Saturn so far that we can start thinking about other things it can do."

VIMS will be able to complement exoplanet studies by space telescopes such as NASA's Hubble and Spitzer space telescopes. VIMS scientists are particularly interested in investigating atmospheric data -- such as signatures of methane -- from far-off star systems in near-infrared wavelengths.

The pointing has to be very accurate to get one of those extrasolar planets in VIMS's viewfinder, but the instrument has had lots of practice pointing at other stars. Earlier this year, VIMS obtained its first successful observation of a transit by the exoplanet HD 189733b. Scientists want to improve these observations by reducing the amount of noise in the signal.

In April, VIMS demonstrated another kind of flexibility by turning its eyes to the warm fissures slashing cross the surface of Saturn's moon Enceladus. VIMS is particularly good at taking thermal data in temperatures around minus 100 degrees Fahrenheit (200 kelvins). So while it is good at tracking hotspots and turbulent clouds on Saturn, VIMS is generally unable to detect thermal emission from Titan, the icy satellites or the rings, since their temperatures are much colder than that.

But the fissures on Enceladus, which scientists have called tiger stripes, are just hot enough for VIMS to detect heat coming from them.

"For the first time, we were able to see that the jets coming from the surface of Enceladus originated in very small, very hot spots," said Bonnie Buratti, a VIMS scientist at NASA's Jet Propulsion Laboratory, Pasadena, Calif. "This new observation is good evidence for liquid water underneath the surface."

VIMS is one of 12 instruments on Cassini, which launched in 1997 and began orbiting Saturn in 2004. "We built Cassini to be hardy, and we're pleased that the spacecraft has been weathering the extreme conditions of the Saturn system remarkably well," said Robert Mitchell, Cassini program manager at JPL. "It isn't too tired to try something new."

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology, Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The visual and infrared mapping spectrometer team is based at the University of Arizona, Tucson.

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Armchair science: Bag and tag glowing galactic clouds

Dec. 20, 2012 — A new galactic game launches today that lets citizen scientists identify the glowing clouds where future stars will be born. The online experience, called Clouds, is a new addition to the Milky Way Project, where everyone can help astronomers to sort and measure our galaxy. Clouds features images and data from NASA's Spitzer Space Telescope and the Herschel Space Observatory, a European Space Agency mission with important participation from NASA.

In the rapid-fire game, players gauge whether a targeted section of a presented image is a cloud, a "hole" -- an empty region of space -- or something in between. The cataloging of these snapshots of the local cosmos will help astronomers learn more about the architecture and character of our home galaxy, the Milky Way.

The organizers of Clouds encourage astronomy enthusiasts to start playing now because with enough participation, important insights into the Milky Way could come as soon as early next year.

"We're really excited to launch Clouds and see results back from our giant volunteer team of amateur scientists," said Robert Simpson, a postdoctoral researcher in astronomy at Oxford University, England and principal investigator of the Milky Way Project. "We think the community can blast through all these data fairly quickly. We may even be done by the spring and that would be an amazing result for citizen science."

Clouds joins its predecessor Milky Way Project game, Bubbles, as one of the many "crowdsourced" efforts underway at Zooniverse, home to the Internet's biggest and most popular online citizen science projects.

The crowdsourcing concept involves having a lot of people evaluate the same image or pieces of data. A consensus decision on some aspect of the image is then reached through the collective "wisdom of crowds." Crowdsourced citizen science becomes especially important when humans can do a better job at analyzing images or objects than a computer can. The Clouds game is an example of just such an exercise in which eyeballs and brains beat out cameras and computer algorithms.

The goal of Clouds is to tag the dense, cold cores of gas and dust known as infrared dark clouds. These clouds collapse under their own gravity and then burst forth as new stars. An empty region of space, however, can look rather like one of these dark clouds and deceive a computer accordingly. "Automated routines have tried to decide which of these objects are holes and which are true infrared dark clouds, but the task is often tricky and it takes a human eye to decide," said Simpson.

Clouds combines infrared observations from Herschel and Spitzer to reveal cool clouds and holes throughout the Milky Way's disk. The Herschel data, at a wavelength of 250 microns, appears in yellow throughout the game. The Spitzer data, at 8 microns, is rendered in blue.

Together with its companion Bubbles game, Clouds serves as another example of how Zooniverse makes cutting-edge scientific investigation freely available to the general public. "Citizen science through Zooniverse has been a real boon to research in fields ranging from astronomy to biology to history," noted Simpson. "We feel very fortunate to be able to send science work out to computer, tablet and smartphone screens and for people to collaborate with us in a quest to better understand our universe."

For those interested in looking for infrared clouds and contributing to the Milky Way Project, visit the following link: http://www.milkywayproject.org. To learn of other citizen science-based efforts, check out the Zooniverse: https://www.zooniverse.org.

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Shot away from its companion, giant star makes waves: Spitzer captures infrared portrait

Dec. 18, 2012 — Like a ship plowing through still waters, the giant star Zeta Ophiuchi is speeding through space, making waves in the dust ahead. NASA's Spitzer Space Telescope has captured a dramatic, infrared portrait of these glowing waves, also known as a bow shock.

Astronomers theorize that this star was once sitting pretty next to a companion star even heftier than itself. But when that star died in a fiery explosion, Zeta Ophiuchi was kicked away and sent flying. Zeta Ophiuchi, which is 20 times more massive and 80,000 times brighter than our sun, is racing along at about 54,000 mph (24 kilometers per second).

In this view, infrared light that we can't see with our eyes has been assigned visible colors. Zeta Ophiuchi appears as the bright blue star at center. As it charges through the dust, which appears green, fierce stellar winds push the material into waves. Where the waves are the most compressed, and the warmest, they appear red. This bow shock is analogous to the ripples that precede the bow of a ship as it moves through the water, or the pileup of air ahead of a supersonic airplane that results in a sonic boom.

NASA's Wide-field Infrared Survey Explorer, or WISE, released a similar picture of the same object in 2011. WISE sees infrared light as does Spitzer, but WISE was an all-sky survey designed to take snapshots of the entire sky. Spitzer, by contrast, observes less of the sky, but in more detail. The WISE image can be seen at: http://www.jpl.nasa.gov/news/news.php?release=2011-026 .

NASA's Jet Propulsion Laboratory, Pasadena, Calif., manages the Spitzer Space Telescope mission for NASA's Science Mission Directorate, Washington. Science operations are conducted at the Spitzer Science Center at the California Institute of Technology in Pasadena. Data are archived at the Infrared Science Archive housed at the Infrared Processing and Analysis Center at Caltech. Caltech manages JPL for NASA. For more information about Spitzer, visit: http://spitzer.caltech.edu and http://www.nasa.gov/spitzer .

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Review of NASA's Ground Systems Development and Operations assesses progress determining infrastructure needs

Dec. 12, 2012 — NASA's Ground Systems Development and Operations (GSDO) Program recently completed an important System Requirements Review/System Definition Review (SRR/SDR) as part of planning for future operations at the agency's Kennedy Space Center. The reviews help establish the groundwork needed to launch NASA's Orion spacecraft atop the Space Launch System (SLS) rocket beginning in 2017.

The SRR/SDR began July 11, with a kickoff meeting in which GSDO presented a summary of its program planning, requirements, architecture and operations documentation required for the milestone. The goal was to determine the center's infrastructure needs for future programs and establish work plans for the preliminary design phase.

"This GSDO team has done superb work in achieving this important milestone," said Pepper Phillips, program manager of Kennedy's GSDO Program Office. "This thorough review has validated that our baseline architecture is sound and aligns with the agency's exploration objectives."

The GSDO Program is determining what systems and facilities will be required to support launching SLS with Orion atop it from Kennedy. Orion is NASA's multi-purpose crew vehicle that will provide a new capability for human exploration beyond low Earth orbit. SLS is a powerful new rocket in development that will take astronauts farther into space than ever before.

"Our mission is to ensure we can process and launch the next generation of launch vehicles and spacecraft," said Tammy Annis, SRR/SDR lead in GSDO. "To meet this goal we need to develop the ground systems, infrastructure and operational approaches to sustain that mission."

The 37-member board reviewed reports on products such as Kennedy's future infrastructure needs, including estimates on cost, schedule and technical data.

"The teams have developed 42 products of which 16 were reviewed during the SRR/SDR process," said Greg Horvath, division chief in GSDO Program Integration.

"These reports included studies by teams that focused on program-level integration, vehicle integration and functional program requirements," he said.

The review board includes representatives from NASA Headquarters, the SLS and Orion Programs, mission operations, the astronaut office and Kennedy intuitional organizations.

GSDO teams specialize in multiple areas of development and operations at Kennedy. The current focus is on establishing program requirements, architectures and operations planning.

The Vehicle Integration and Launch team researches the equipment, management and operations required to safely attach a spacecraft to a rocket, move the launch vehicle to the pad and successfully send it into space.

The Offline Processing and Integration Team is developing ways to process the Orion spacecraft, rocket stages and the launch abort system before they are assembled into one vehicle.

Another group is modernizing the Command, Control, Communications and Range Systems involved in launching astronauts into space. In addition to bringing computers, tracking systems and other networks up-to-date, the team is creating systems that can manage several different kinds of spacecraft and rockets.

Unlike previous work focusing on a single kind of launch vehicle, such as the Saturn V rocket or space shuttle, engineers and managers in GSDO are preparing infrastructure to support several different kinds of spacecraft and rockets that are in development.

"Our focus on this review is the ground infrastructure of Orion and SLS," Horvath said. "However, we are continuing to evaluate strategic investment opportunities that will enable us to best align the unique capabilities of the Kennedy Space Center with commercial space pursuits as those plans mature."

Horvath explained that is important for the GSDO, SLS and Orion Programs to work closely together so that they all get to the planned first launch in 2017.

"We're focusing on building ground systems with interfaces to flight vehicles," he said. "Orion's systems are reasonably mature, with hardware already here at Kennedy. The SLS design is less mature at this stage, so we have to continue discussions with the people in Flight Systems as we design the integration facilities and mobile launcher umbilical connecting points between ground systems and the rocket."

Tim Honeycutt, the Technical Management branch chief in GSDO Program Integration, says that he is pleased with progress so far.

"We've determined what the issues are and we're developing a good strategy to mitigate them," he said. "It positions us well as we move forward." The next step, the Preliminary Design Review, begins in November 2013.

"That review will allow us to evaluate preliminary designs of new systems here at Kennedy and better establish where we need to make prudent modifications to existing systems," Honeycutt said.

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Apollo's lunar dust data being restored

Dec. 6, 2012 — Forty years after the last Apollo spacecraft launched, the science from those missions continues to shape our view of the moon. In one of the latest developments, readings from the Apollo 14 and 15 dust detectors have been restored by scientists with the National Space Science Data Center (NSSDC) at NASA's Goddard Space Flight Center in Greenbelt, Md.

"This is the first look at the fully calibrated, digital dust data from the Apollo 14 and 15 missions," said David Williams, a Goddard scientist and data specialist at NSSDC, NASA's permanent archive for space science mission data.

The newly available data will make long-term analysis of the Apollo dust readings possible. Digital data from these two experiments were not archived before, and it's thought that roughly the last year-and-a-half of the data have never been studied.

The work was presented on December 6 at the American Geophysical Union meeting in San Francisco, as part of a session organized in honor of the 40th anniversary of the Apollo 17 launch. Also presented in this session was a similar effort to fill in gaps in the Apollo 15 and 17 heat-flow measurements, the only such measurements ever taken on the moon or any planetary body other than Earth.

The recovery of these data sets is part of the Lunar Data Project, an ongoing NSSDC effort, drawing on researchers at multiple institutions, to make the scientific data from Apollo available in modern formats.

The Lunar Dust Detectors that were placed on the lunar surface during Apollo 14 and 15 measured dust accumulation, temperature and damage caused by high-energy cosmic particles and the sun's ultraviolet radiation. The same kind of instrument had flown earlier on Apollo 11 and 12 (Later, Apollo 17 carried a different type of dust detector).

Restoring the data was a painstaking job of going through one data set and separating the raw detector counts from temperatures and "housekeeping" information that was collected to keep an eye on how healthy the Apollo instruments were. A second, less complete data set indicated how to convert the raw counts into usable measurements. But first, the second data set had to be converted from microfilm, which had been archived at NSSDC in the 1970s, and the two data sets had to reconciled because their time points didn't match up exactly. Most of this meticulous work was carried out by Marie McBride, an undergraduate from the Florida Institute of Technology in Melbourne who was working with Williams through a NASA internship.

Newer missions, such as NASA's Lunar Reconnaissance Orbiter (LRO), have continued to study lunar dust. "It's one of those questions that scientists keep coming back to," said McBride.

"Just last week, LRO did some important measurements seeking dust profiles in the lunar atmosphere," said Rich Vondrak, the LRO deputy project scientist at NASA Goddard. LRO has been orbiting the moon since June 2009, and the mission was recently extended through 2015.

And the main objective of NASA's Lunar Atmosphere and Dust Environment Explorer (LADEE), scheduled to launch in 2013, is to characterize the moon's atmosphere and dust environment.

This offers another example of how profoundly influential the Apollo data continues to be, observed Noah Petro, a member of the LRO project science team at NASA Goddard. "A mission ends when it ends, but the science continues forever."

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CubeSats in orbit after historic space station deployment

Dec. 11, 2012 — Typically satellites launch from Earth, requiring dedicated launch vehicles to propel them into the proper orbit. The cost for this launch scenario could be reduced considerably if there was another way to get the satellites into their optimal orbit. The Japan Aerospace and Exploration Agency (JAXA) found a way to cut the costs of this activity by designing a small satellite launcher, installed recently on the International Space Station.

The Japanese Experiment Module (JEM) Small Satellite Orbital Deployer (J-SSOD) is capable of launching small satellites from the station, using the JEM Remote Manipulator System, which is like a small robotic arm. In the Small Sat Deploy-Demo, the remote robotic system grappled and retrieved the Multi-Purpose Experiment Platform, where the J-SSOD is installed and loaded with the small satellite(s). There are two chutes on the deployer, with each chute holding up to three satellites. While attached to the robotic arm, the platform is released from the JEM Airlock, and positioned away from the station for safe deployment of the satellites.

The deployer allows for additional launch opportunities for these miniature satellites, while demonstrating new technologies for air, water and surface monitoring. This is a new capability for the space station, allowing for the launch of smaller satellites from a permanently manned orbiting vehicle.

The J-SSOD also allows the crew to power up the satellites right before deployment, as opposed to when the satellites are loaded onto the launch vehicles. This not only extends the battery life, but allows the crew to check functionality and make simple repairs, if necessary. Since the mini-satellites, or CubeSats, are delivered to the space station packed securely inside a vehicle, vibrations and environmental changes are less of a concern. These changes allow for a range of new future possibilities regarding small satellite design.

CubeSats are small satellites introduced in 1999 and designed by California Polytechnic State University. They are approximately 4 inch (10 centimeter) cubes, weighing no more than 2.7 pounds (1.2 kilograms). Each satellite produces its own power, and is designed with solar panels and capable of transmitting signals. The J-SSOD and the five satellites deployed in this demonstration arrived at the station on the JAXA H-II Transfer Vehicle 3 (HTV-3) earlier this summer. Students designed and built all of the satellites, with the exception of one.

A demonstration of this new technology was performed Oct. 4, deploying five CubeSats, from the Kibo Laboratory, another name for the JEM. JAXA astronaut Aki Hoshide commanded the first deployment from the station, with the second commanded from the ground control team. Using the JEM Remote Manipulator System, Hoshide assisted with the deployment of the satellites that involved several different investigations.

RAIKO, a JAXA satellite, is poised to take photos of Earth through a fish-eye lens camera. This technology demonstration is expected to measure the movement of the satellite, as it deploys, through photographs during the process, along with testing of a star sensor. Star sensors help with spacecraft attitude determination. This is a two unit satellite and is larger than the others.

FITSAT-1, also a JAXA satellite, is testing a high-speed transmission module for small satellites, using visible light to communicate by high power LED flashes. The goal is to transmit data close to 100 times faster than current CubeSats. The LEDs are so bright, they might even be seen from Japanese ground sites. The plan is for this satellite to flash LED messages across the sky in Morse code.

JAXA's WE WISH satellite is slated to contribute to local technology education, promoting the use of data acquired by small satellites. An ultra-small thermal infrared camera will transmit images back to a ground site. Local ham radio operators also are expected to receive data from WE WISH.

F-1, a NanoRacks customer CubeSat, is an educational satellite for FPT University of Vietnam. This satellite takes photos of Earth to capture atmospheric changes, and possibly tracking ship traffic, as well as detect forest fires. Students also are using this satellite to measure Earth's magnetic field and temperatures in the space environment, along with several radio/communications experiments.

Jeffrey Manber, managing director for NanoRacks, said, "One of the beauties of CubeSat is the building of the cube satellite is an education in itself, leading a new generation to the field of engineering." Manber added that this was truly an international collaboration -- NanoRacks working with NASA, using a JAXA facility to deploy a Vietnamese satellite. NanoRacks is the first company to arrange for the deployment of a commercial satellite.

TechEdSat is an educational investigation and a technology demonstration, designed and built by San Jose State University students. The goals of this investigation are to evaluate Space Plug-and-Play Avionics, and test for tracking and communication capabilities using the Iridium and Orbcomm satellite phone systems. The satellite design allows it to transmit temperature, elapsed time, voltage and current, along with any error messages back via ham radio to the students.

"The deployment of the CubeSats from [the space station] can be timed to match a sudden increase in solar activity, observations of disaster areas, [or] support of other larger and higher satellite research objectives," said Al Holt, principal investigator for the J-SSOD. "Support of other [station] payloads and student and educational objectives tied to specific time periods," are also options. Using this deployer to launch small satellites not only reduces the cost for this activity, but also allows for much greater flexibility.

Lead Increment Scientist for Expedition 33/34 Vic Cooley said about the demonstration, "This is all about adding yet one more capability to our wonderful space station." The station is already being used as a research laboratory, a test bed, and possibly as a stepping stone for moving beyond low-Earth orbit. To learn more about this small satellite deployment system, watch this interview with Cooley.

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X-ray vision can reveal moment of birth of violent supernovae

Dec. 7, 2012 — A team of astronomers led by the University of Leicester has uncovered new evidence that suggests that X-ray detectors in space could be the first to witness new supernovae that signal the death of massive stars.

Astronomers have measured an excess of X-ray radiation in the first few minutes of collapsing massive stars, which may be the signature of the supernova shock wave first escaping from the star.

The findings have come as a surprise to Dr Rhaana Starling, of the University of Leicester Department of Physics and Astronomy whose research is published in the Monthly Notices of the Royal Astronomical Society.

Dr Starling said: "The most massive stars can be tens to a hundred times larger than the Sun. When one of these giants runs out of hydrogen gas it collapses catastrophically and explodes as a supernova, blowing off its outer layers which enrich the Universe. But this is no ordinary supernova; in the explosion narrowly confined streams of material are forced out of the poles of the star at almost the speed of light. These so-called relativistic jets give rise to brief flashes of energetic gamma-radiation called gamma-ray bursts, which are picked up by monitoring instruments in Space, that in turn alert astronomers."

Gamma-ray bursts are known to arise in stellar deaths because coincident supernovae are seen with ground-based optical telescopes about ten to twenty days after the high energy flash. The true moment of birth of a supernova, when the star's surface reacts to the core collapse, often termed the supernova shock breakout, is missed. Only the most energetic supernovae go hand-in-hand with gamma-ray bursts, but for this sub-class it may be possible to identify X-ray emission signatures of the supernova in its infancy. If the supernova could be detected earlier, by using the X-ray early warning system, astronomers could monitor the event as it happens and pinpoint the drivers behind one of the most violent events in our Universe.

The X-ray detectors being used for this research, built partly in the UK at the University of Leicester, are on the X-Ray Telescope on-board the Swift satellite. Swift is named after the bird because, like its namesake, it is able to swiftly turn around to catch a gamma-ray burst in action. Data from Swift of a number of gamma-ray bursts with visible supernovae have shown an excess in X-rays received compared with expectations. This excess is thermal emission, also known as blackbody radiation.

Dr Starling added: "We were surprised to find thermal X-rays coming from a gamma-ray burst, and even more surprising is that all confirmed cases so far are those with a secure supernova identification from optical data. This phenomenon is only seen during the first thousand seconds of an event, and it is challenging to distinguish it from X-ray emission solely from the gamma-ray burst jet. That is why astronomers have not routinely observed this before, and only a small subset of the 700+ bursts we detect with Swift show it."

"It all hangs on the positive identification of the extra X-ray radiation as directly emerging from the supernova shock front, rather than from the relativistic jets or central black hole. If this radiation turns out to be from the central black-hole-powered engine of the gamma-ray burst instead, it will still be a very illuminating result for gamma-ray burst physics, but the strong association with supernovae is tantalising."

The team, comprising scientists from the UK, Ireland, USA and Denmark, plan to extend their searches, and make more quantitative comparisons with theoretical models both for stellar collapse and the dynamics of fast jet-flows.

Astronomers will continue to view supernovae at their visible-light peak, when they are already tens of days old, but for the most energetic among them it may become possible to routinely witness the very moment they are born, through X-ray eyes.

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Journal References:

R. L. C. Starling, K. L. Page, A. Pe'er, A. P. Beardmore and J. P. Osborne. A search for thermal X-ray signatures in gamma-ray bursts – I. Swift bursts with optical supernovae. Monthly Notices of the Royal Astronomical Society, 28 NOV 2012 DOI: 10.1111/j.1365-2966.2012.22116.xMartin Sparre and Rhaana L. C. Starling. A search for thermal X-ray signatures in gamma-ray bursts – II. The Swift sample. Monthly Notices of the Royal Astronomical Society, 28 NOV 2012 DOI: 10.1111/j.1365-2966.2012.21858.x

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Complex chemistry within the Martian soil: No definitive detection of organics yet

Dec. 3, 2012 — NASA's Mars Curiosity rover has used its full array of instruments to analyze Martian soil for the first time, and found a complex chemistry within the Martian soil. Water and sulfur and chlorine-containing substances, among other ingredients, showed up in samples Curiosity's arm delivered to an analytical laboratory inside the rover.

Detection of the substances during this early phase of the mission demonstrates the laboratory's capability to analyze diverse soil and rock samples over the next two years. Scientists also have been verifying the capabilities of the rover's instruments.

Curiosity is the first Mars rover able to scoop soil into analytical instruments. The specific soil sample came from a drift of windblown dust and sand called "Rocknest." The site lies in a relatively flat part of Gale Crater still miles away from the rover's main destination on the slope of a mountain called Mount Sharp. The rover's laboratory includes the Sample Analysis at Mars (SAM) suite and the Chemistry and Mineralogy (CheMin) instrument. SAM used three methods to analyze gases given off from the dusty sand when it was heated in a tiny oven. One class of substances SAM checks for is organic compounds -- carbon-containing chemicals that can be ingredients for life.

"We have no definitive detection of Martian organics at this point, but we will keep looking in the diverse environments of Gale Crater," said SAM Principal Investigator Paul Mahaffy of NASA's Goddard Space Flight Center in Greenbelt, Md.

Curiosity's APXS instrument and the Mars Hand Lens Imager (MAHLI) camera on the rover's arm confirmed Rocknest has chemical-element composition and textural appearance similar to sites visited by earlier NASA Mars rovers Pathfinder, Spirit and Opportunity.

Curiosity's team selected Rocknest as the first scooping site because it has fine sand particles suited for scrubbing interior surfaces of the arm's sample-handling chambers. Sand was vibrated inside the chambers to remove residue from Earth. MAHLI close-up images of Rocknest show a dust-coated crust one or two sand grains thick, covering dark, finer sand.

"Active drifts on Mars look darker on the surface," said MAHLI Principal Investigator Ken Edgett, of Malin Space Science Systems in San Diego."This is an older drift that has had time to be inactive, letting the crust form and dust accumulate on it."

CheMin's examination of Rocknest samples found the composition is about half common volcanic minerals and half non-crystalline materials such as glass. SAM added information about ingredients present in much lower concentrations and about ratios of isotopes. Isotopes are different forms of the same element and can provide clues about environmental changes. The water seen by SAM does not mean the drift was wet. Water molecules bound to grains of sand or dust are not unusual, but the quantity seen was higher than anticipated.

SAM tentatively identified the oxygen and chlorine compound perchlorate. This is a reactive chemical previously found in arctic Martian soil by NASA's Phoenix Lander. Reactions with other chemicals heated in SAM formed chlorinated methane compounds -- one-carbon organics that were detected by the instrument. The chlorine is of Martian origin, but it is possible the carbon may be of Earth origin, carried by Curiosity and detected by SAM's high sensitivity design.

"We used almost every part of our science payload examining this drift," said Curiosity Project Scientist John Grotzinger of the California Institute of Technology in Pasadena. "The synergies of the instruments and richness of the data sets give us great promise for using them at the mission's main science destination on Mount Sharp."

NASA's Mars Science Laboratory Project is using Curiosity to assess whether areas inside Gale Crater ever offered a habitable environment for microbes. NASA's Jet Propulsion Laboratory in Pasadena manages the project for NASA's Science Mission Directorate in Washington.

For more information about Curiosity and other Mars mission, visit: http://www.nasa.gov/mars

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Giant black hole could upset galaxy evolution models

Nov. 27, 2012 — A group of astronomers led by Remco van den Bosch from the Max Planck Institute for Astronomy (MPIA) have discovered a black hole that could shake the foundations of current models of galaxy evolution. At 17 billion times the mass of the Sun, its mass is much greater than current models predict -- in particular since the surrounding galaxy is comparatively small. This could be the most massive black hole found to date.

To the best of our astronomical knowledge, almost every galaxy should contain in its central region what is called a supermassive black hole: a black hole with a mass between that of hundreds of thousands and billions of Suns. The best-studied super-massive black hole sits in the center of our home galaxy, the Milky Way, with a mass of about four million Suns.

For the masses of galaxies and their central black holes, an intriguing trend has emerged: a direct relationship between the mass of a galaxy's black hole and that of the galaxy's stars.

Typically, the black hole mass is a tiny fraction of the galaxy's total mass. But now a search led by Remco van den Bosch (MPIA) has discovered a massive black hole that could upset the accepted relationship between black hole mass and galaxy mass, which plays a key role in all current theories of galaxy evolution. The observations used the Hobby-Eberly Telescope and existing images from the Hubble Space Telescope.

With a mass 17 billion times that of the Sun, the newly discovered black hole in the center of the disk galaxy NGC 1277 might even be the biggest known black hole of all: the mass of the current record holder is estimated to lie between 6 and 37 billion solar masses (McConnell et al. 2011); if the true value lies towards the lower end of that range, NGC 1277 breaks the record. At the least, NGC 1277 harbors the second-biggest known black hole.

The big surprise is that the black hole mass for NGC 1277 amounts to 14% of the total galaxy mass, instead of usual values around 0,1%. This beats the old record by more than a factor 10. Astronomers would have expected a black hole of this size inside blob-like ("elliptical") galaxies ten times larger. Instead, this black hole sits inside a fairly small disk galaxy.

Is this surprisingly massive black hole a freak accident? Preliminary analysis of additional data suggests otherwise -- so far, the search has uncovered five additional galaxies that are comparatively small, yet, going by first estimates, seemed to harbor unusually large black holes too. More definite conclusions have to await detailed images of these galaxies.

If the additional candidates are confirmed, and there are indeed more black holes like this, astronomers will need to rethink fundamentally their models of galaxy evolution. In particular, they will need to look at the early universe: The galaxy hosting the new black hole appears to have formed more than 8 billion years ago, and does not appear to have changed much since then. Whatever created this giant black hole must have happened a long time ago.

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Journal Reference:

Remco C. E. van den Bosch, Karl Gebhardt, Kayhan Gültekin, Glenn van de Ven, Arjen van der Wel, Jonelle L. Walsh. An over-massive black hole in the compact lenticular galaxy NGC?1277. Nature, 2012; 491 (7426): 729 DOI: 10.1038/nature11592

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NASA seeks concepts for innovative uses of large space telescopes

Nov. 28, 2012 — NASA is exploring options for innovative and imaginative uses of two large space telescopes recently transferred to the agency. In a request for information (RFI) published Monday, NASA seeks information about system concepts and architectures that would take advantage of these assets to address NASA's goals in astrophysics, heliophysics, planetary sciences, and human spaceflight.

"Because there are two telescopes, there is room for projects that span the gamut of the imagination," said Michael Moore, a senior program executive at NASA Headquarters in Washington. "They range from simple balloon flights to complex missions in science using new technologies under development and the capabilities available with the International Space Station and our commercial space flight partners."

The telescopes are equivalent to NASA's Hubble Space Telescope in aperture, but designed to have a much wider field of view. They already are being studied for possible use as a wide field infrared survey observatory, which would address the top priority recommendation in the National Research Council's 2010 Astrophysics Decadal Survey. NASA is seeking alternative goals and unique approaches in order to expand the range of concepts for use of this capable hardware.

The RFI invites interested parties to provide an outline of their concept in enough detail for a next-step assessment by NASA as it prepares for future investments in diverse areas of science and technology. Respondents who submit the most interesting concepts will be invited to present their ideas at a workshop in Huntsville, Ala., in early February 2013.

"We will give all ideas equal consideration and choose the most promising for further study," said Marc Allen, acting deputy associate administrator for research in NASA's Science Mission Directorate. "We want to tap into innovative ideas wherever we can find them in order to optimize use of these telescope assets."

For more information about the RFI, NASA goals and objectives, details on the telescopes, and other supporting information, visit: http://science.nasa.gov/salso

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Swirling storms on Saturn

Dec. 3, 2012 — NASA's Cassini spacecraft has been traveling the Saturnian system in a set of inclined, or tilted, orbits that give mission scientists a vertigo-inducing view of Saturn's polar regions. This perspective has yielded images of roiling storm clouds and a swirling vortex at the center of Saturn's famed north polar hexagon.

These phenomena mimic what Cassini found at Saturn's south pole a number of years ago. Cassini has also seen storms circling Saturn's north pole in the past, but only in infrared wavelengths because the north pole was in darkness. But, with the change of the Saturnian seasons, the sun has begun to creep over the planet's north pole.

This particular set of raw, unprocessed images was taken on Nov. 27, 2012, from a distance of about 250,000 miles (400,000 kilometers) from Saturn.

More raw images are available at http://saturn.jpl.nasa.gov/photos/raw/index.cfm .

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. JPL, a division of the California Institute of Technology in Pasadena, manages the Cassini-Huygens mission for NASA's Science Mission Directorate, Washington. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging team is based at the Space Science Institute in Boulder, Colo.

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Autumn sets in rapidly on Saturn's giant moon

Nov. 28, 2012 — As leaves fall and winter approaches in Earth's Northern Hemisphere, a change of seasons is also rapidly becoming noticeable in the southern hemisphere of Saturn's giant moon, Titan.

Thanks to NASA's Cassini spacecraft which has been orbiting Saturn since 2004, scientists have been able to observe for the first time ever the seasonal atmospheric circulation direction change on Titan -- an event which only happens once every 15 years and is never observable from Earth. Their findings are published today in Nature.

Titan, while technically only a moon, is bigger than the planet Mercury, and is often considered a planet in its own right. It is the only known moon to have a significant atmosphere and is one of only four terrestrial atmospheres in our Solar System (the other three being Earth, Venus, and Mars). As Titan's rotation axis is tilted by a similar amount to that of Earth, it experiences seasons in a similar way, but at a much more relaxed pace as Saturn takes 29.5 Earth years to orbit the Sun.

Dr Nick Teanby of the University of Bristol and colleagues used infrared spectra measured by Cassini's Composite InfraRed Spectrometer (CIRS) instrument to determine atmospheric temperature and global distributions of chemical tracers. This allowed them to map out the seasonal changes in great detail.

The team observed an enormous increase in Titan's exotic trace gases over the south pole within a relatively short time. These trace gases are produced high in Titan's atmosphere, where sunlight and highly energetic particles break down nitrogen and methane and recombine to form a vast array of more complex molecules like benzene and hydrogen cyanide.

Co-author, Dr Remco de Kok of SRON Netherlands Institute for Space Research said: "We were waiting for signs that the trace gas abundances would change together with the new season, but we did not expect such a large and rapid change: some gas concentrations increased more than a thousand times within only a few months. Also surprising was that this was happening at altitudes above 450 km, much higher than initially anticipated."

At these high altitudes the atmosphere goes around the planet much faster than the rotation of Titan's solid surface and can have horizontal wind speeds around the planet of up to 200m/s (450mph). Vertical winds caused by the seasonally varying hemisphere to hemisphere atmospheric circulation are much slower at a rather sluggish few millimetres per second and are hard to measure using conventional means.

Lead author, Dr Nick Teanby of Bristol's School of Earth Sciences said: "Using measurements of temperature and chemical tracers by Cassini, we were able to observe changes in the subtle vertical winds and reveal the pole-to-pole circulation cell. For the first time ever, we observed the circulation cell direction reverse over the south pole around the time of the 2009 southern autumnal equinox. The resulting distribution of gases shows that the circulation must extend much further than previously thought to 600 km or even higher. This calls into question our current understanding of how Titan's atmosphere works and suggests new avenues to explore."

"Our results provide a powerful new constraint for atmospheric models of Titan. Titan provides a natural laboratory for an Earth-like atmosphere in the cold outer solar system. So, these results could eventually lead to a more complete understanding of atmospheric processes on Earth, other Solar System planets, and the many exoplanetary systems now being discovered."

In the coming years Cassini will continue to observe how the seasons develop. Dr Conor Nixon at NASA Goddard Space Flight Centre said: "These results are giving us the first detailed look at changes occurring in Titan's atmosphere around the time of equinox, a season which has not been viewed up close by a spacecraft previously. This shows the really great science that is coming out of the Cassini extended mission phases since 2008, and we look forward to seeing the further changes that will occur over the next five years until the end of mission in 2017."

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Nicholas A. Teanby, Patrick G. J. Irwin, Conor A. Nixon, Remco de Kok, Sandrine Vinatier, Athena Coustenis, Elliot Sefton-Nash, Simon B. Calcutt, F. Michael Flasar. Active upper-atmosphere chemistry and dynamics from polar circulation reversal on Titan. Nature, 2012; 491 (7426): 732 DOI: 10.1038/nature11611

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Airborne scientists search distant stars for complex organic molecules

Dec. 10, 2012 — A team of astrobiology researchers -- including two from Rensselaer Polytechnic Institute -- will use a series of nighttime flights on an airborne observatory to search newly born stars for the presence of precursors to life.

The scientists, led by Douglas Whittet, director of the New York Center for Astrobiology at Rensselaer, will use the observatory's infrared absorption spectroscopy capabilities to search for a suite of molecules in clouds of dust surrounding five young stars. Their work is part of the first season, or cycle, of research to be performed aboard the Statospheric Observatory for Infrared Astronomy (SOFIA), the largest airborne observatory in the world.

A partnership of NASA and the German Aerospace Center, SOFIA consists of an extensively modified Boeing 747SP aircraft carrying a reflecting telescope with an effective diameter of 2.5 meters (100 inches). The airborne observatory, based at NASA's Dryden Aircraft Operations Facility in California, began a planned-20 year lifetime with its first cycle from November 2012 to December 2013.

"We're interested in how the matter that you need to make planetary life came to be: Where did it come from and how was it formed? And since it happened here in our solar system, is it likely to happen elsewhere as well?" said Whittet, also a professor of physics. "We can't go back in time to observe our solar system when it was born, but we can look at other regions that we believe are similar and use them as analogs for the early solar system."

The scientists will determine the chemical composition of distant regions through absorption spectrometry, a technique that takes advantage of the fact that different types of matter absorb different segments of the wavelength spectrum generated by a given source of energy -- in this case, the newly born star.

Whittet explained that the infrared spectra of newly born stars are rich in absorption features that signal the presence of organic molecules and water in the dusty remnants of the clouds from which they formed. These dusty remnants are the raw materials from which new planets may coalesce.

Aboard SOFIA, the scientists will be looking at the absorption spectrum of infrared light at wavelengths between 5 and 8 microns. The researchers will search for molecules such as methane, ammonia, formaldehyde, methanol, and formic acid -- early precursors of amino acids. The work is a collaboration between Whittet and Charles Poteet, a post-doctoral research associate at Rensselaer, and researchers at SETI, the California Institute of Technology, Ithaca College, the NASA Ames Research Center, and Johns Hopkins University.

The current project builds upon recent work in which the scientists combined years of existing research to locate areas in outer space that have extreme potential for complex organic molecule formation. Whittet and his collaborators searched for indications of methanol, a key ingredient in the synthesis of organic molecules that could lead to life, and identified a handful of newly formed stars that are surrounded by clouds with a high concentration of methanol (about 30 percent).

For that project, the scientists were able to rely on observations made from ground-based telescopes, but Whittet said only SOFIA has the capability to gather the more specific data they currently seek.

"We're trying to look at a part of the spectrum that doesn't get through the atmosphere very well," Whittet said. "Earth's atmosphere, which contains a lot of moisture, absorbs most of the infrared radiation we want to detect. But SOFIA cruises at an altitude of about 40,000 feet, which is above almost all of the moisture, and allows us an unimpeded view of the stars."

Further, said Whittet, although two space-based instruments equipped with infrared absorption spectrometry capabilities -- NASA's Spitzer Space Telescope, and the Infrared Space Observatory, a European Space Agency satellite -- did take observations in that region, neither of them had the appropriate combination of resolution and sensitivity for the group's current work.

"There's really nothing else out there right now that could collect the data we need for this research," Whittet said.

The scientists were awarded 6.5 hours aboard SOFIA, time which may be used in one or several flights over the Pacific Ocean, and Whittet hopes he will be aboard for the observations. He said the scientists will likely publish findings from their research within a year after collecting the data.

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Martian dust storm dissipating

Nov. 28, 2012 — A regional dust storm on Mars, tracked from orbit since Nov. 10, appears to be abating rather than going global.

"During the past week, the regional storm weakened and contracted significantly," said Bruce Cantor of Malin Space Science Systems, San Diego. Cantor uses the Mars Color Imager camera on NASA's Mars Reconnaissance Orbiter to monitor storms on the Red Planet.

Effects of the storm on global air-pressure patterns have been detected at ground level by the Rover Environmental Monitoring Station (REMS) on NASA's Mars rover Curiosity.

"We are getting lots of good data about this storm," said Mark Richardson of Ashima Research, Pasadena, Calif. He is a co-investigator both on REMS and on the Mars Reconnaissance Orbiter's Mars Climate Sounder instrument, which has been detecting widespread effects of the current storm on atmospheric temperatures.

Researchers anticipate that the unprecedented combination of a near-equatorial weather station at ground level, and daily orbital observations during Mars' dust-storm season, may provide information about why some dust storms grow larger than others.

NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology, Pasadena, manages the Mars Reconnaissance Orbiter Project and the Mars Science Laboratory Project for NASA's Science Mission Directorate, Washington. Spain provided the REMS weather station for the Mars Science Laboratory mission's rover, Curiosity.

For more information about the missions of NASA's Mars Exploration Program, visit http://marsprogram.jpl.nasa.gov/ .

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Botany experiment will try out zero gravity aboard space station

Dec. 18, 2012 — Gravity: It's the law in these parts. But to reach the stars, humans may have to learn to live outside the law.

"Gravity is the most pervasive thing on the planet, and it's always been there," says Simon Gilroy, University of Wisconsin-Madison botany professor. "Terrestrial biology has evolved with this constant force in the background, and when you remove it, things start to happen that you wouldn't necessarily think of."

Surprises are not welcome in space, especially surprises that interrupt the supply of vital oxygen, water and food.

For travel beyond a narrow envelope around Earth, the connection to those supplies is -- for all intents and purposes -- severed. It just takes too many resources to deliver supplementary meals and air as astronauts stray farther and farther from home.

"The only life support system we know that works really, really well is the Earth's, and that is built around plants and microbes," Gilroy says. "It's not 100 percent clear it will work, but the long-term goal is to integrate those tools into space missions: plants to grow your food and purify the air and water; microbes as the waste-processing system."

In March, Gilroy hopes to contribute a small piece of the knowledge that may support such a life-sustaining system by sending a canister full of plants to the International Space Station. Both engineered mutant and unadulterated versions of Arabidopsis -- known commonly as mouse-eared cress, and to researchers as "the lab rat of plant biology," says Gilroy -- will make the trip to study the effect of low-oxygen conditions on the plants' genes.

Without the pull of gravity, plant roots are going to have the same problem that makes a lava lamp a lot less fun in space.

"The reason is buoyancy," Gilroy says. "The goopy stuff in a lava lamp heats up, expands and gets less dense. Buoyancy moves it up in the lamp, where it cools down and sinks. And it all starts over."

Buoyancy depends on relative differences in volume and weight, and is driven by gravity. Without buoyancy, there's no convection, and on Earth convection helps mix gases in the atmosphere.

"If you were just lying on your back in the International Space Station, the gases that you're breathing out -- if there [were] no other things like fans to move the air -- would just sit there around your head," Gilroy says. "You would suffocate, because there's no mixing to replace the oxygen you use up."

Plant roots use oxygen, too. They burn it along with glucose to make energy to drive a growing plant. But the little bit of convection-driven gas mixing plants count on in Earth's soil doesn't happen in space, and the available oxygen gets used up.

For a plant, this low oxygen level is akin to what happens when a neighboring river spills its banks. Corn in a flooded field can survive a few days, but eventually the water will replace air pockets in the soil.

"Just like humans, plants suffocate and die," Gilroy says. "Plants can grow in space, but it may be that they don't grow very well. And one of the reasons is trying to cope with this oxygen depletion."

Gilroy's lab studies the way plants deal with stress, including the signals plant cells pass to one another in times of trouble -- like during a flood.

"If I flood a plant, within seconds, cells in that plant will be sending signals to other cells all over, saying, 'We need to get our act together to deal with this,'" Gilroy says.

Gilroy's lab will send Arabidopsis seeds to the International Space Station aboard a SpaceX Dragon capsule scheduled to launch in March. The seeds will germinate in space in a small container called Biological Research in a Canister (BRIC). After eight days of growth in a gravity-free environment, astronauts will stop the plants' development with a dose of a chemical fixative and tuck the whole BRIC in a deep freeze.

The entire frozen BRIC will return on the same Dragon craft it rode up, and be turned over whole to Gilroy -- who will then treat it like his firstborn child.

"As everyone who has done space shots has told us: you will never let those samples out of your sight once they're back," says Gilroy, whose experiment is funded by NASA. "They're just too valuable."

Arabidopsis grown in a NASA lab that simulates space station conditions (aside from lack of gravity) will be compared to the space plants for physical and genetic differences.

"We should be able to say this is the fingerprint of what low-oxygen looks like," Gilroy says. "We'll be able to say these plants in space look like the plants that were grown on the ground in this particular low oxygen concentration."

That will contribute to the understanding of long-term plant growth in space, and put future space travelers a hair closer to the company of plant life.

"This is that bit of the science where we're beginning to tease apart the system, beginning to understand the components that we can put together to great use," Gilroy says.

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NASA probes prepare for mission-ending moon impact

Dec. 13, 2012 — Twin lunar-orbiting NASA spacecraft that have allowed scientists to learn more about the internal structure and composition of the moon are being prepared for their controlled descent and impact on a mountain near the moon's north pole at about 2:28 p.m. PST (5:28 p.m. EST) Monday, Dec. 17.

Ebb and Flow, the Gravity Recovery and Interior Laboratory (GRAIL) mission probes, are being sent purposely into the lunar surface because their low orbit and low fuel levels preclude further scientific operations. The duo's successful prime and extended science missions generated the highest-resolution gravity field map of any celestial body. The map will provide a better understanding of how Earth and other rocky planets in the solar system formed and evolved.

"It is going to be difficult to say goodbye," said GRAIL principal investigator Maria Zuber of the Massachusetts Institute of Technology in Cambridge. "Our little robotic twins have been exemplary members of the GRAIL family, and planetary science has advanced in a major way because of their contributions."

The mountain where the two spacecraft will make contact is located near a crater named Goldschmidt. Both spacecraft have been flying in formation around the moon since Jan. 1, 2012. They were named by elementary school students in Bozeman, Mont., who won a contest. The first probe to reach the moon, Ebb, also will be the first to go down, at 2:28:40 p.m. PST. Flow will follow Ebb about 20 seconds later.

Both spacecraft will hit the surface at 3,760 mph (1.7 kilometers per second). No imagery of the impact is expected because the region will be in shadow at the time.

Ebb and Flow will conduct one final experiment before their mission ends. They will fire their main engines until their propellant tanks are empty to determine precisely the amount of fuel remaining in their tanks. This will help NASA engineers validate fuel consumption computer models to improve predictions of fuel needs for future missions.

"Our lunar twins may be in the twilight of their operational lives, but one thing is for sure, they are going down swinging," said GRAIL project manager David Lehman of NASA's Jet Propulsion Laboratory in Pasadena, Calif. "Even during the last half of their last orbit, we are going to do an engineering experiment that could help future missions operate more efficiently."

Because the exact amount of fuel remaining aboard each spacecraft is unknown, mission navigators and engineers designed the depletion burn to allow the probes to descend gradually for several hours and skim the surface of the moon until the elevated terrain of the target mountain gets in their way. The burn that will change the spacecrafts' orbit and ensure the impact is scheduled to take place Friday morning, Dec. 14.

"Such a unique end-of-mission scenario requires extensive and detailed mission planning and navigation," said Lehman. "We've had our share of challenges during this mission and always come through in flying colors, but nobody I know around here has ever flown into a moon mountain before. It'll be a first for us, that's for sure."

During their prime mission, from March through May, Ebb and Flow collected data while orbiting at an average altitude of 34 miles (55 kilometers). Their altitude was lowered to 14 miles (23 kilometers) for their extended mission, which began Aug. 30 and sometimes placed them within a few miles of the moon's tallest surface features.

JPL manages the GRAIL mission for NASA's Science Mission Directorate in Washington. The mission is part of the Discovery Program managed at NASA's Marshall Space Flight Center in Huntsville, Ala. Lockheed Martin Space Systems in Denver built the spacecraft. JPL is a division of the California Institute of Technology in Pasadena.

For more information about GRAIL, visit: http://www.nasa.gov/grail .

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How white dwarfs mimic black holes

Dec. 17, 2012 — A remarkable observation by astronomers from the University of Southampton, Professor Phil Charles, Professor Malcolm Coe and postgraduate student Liz Bartlett, has appeared in The Astrophysical Journal.

The Southampton Physics and Astronomy team are part of a global collaboration -- with colleagues in Taiwan, South Africa, Poland, Australia and Italy -- that has revealed that bright X-ray flares in nearby galaxies, once assumed to indicate the presence of black holes, can in fact be produced by white dwarfs.

They made the discovery by detecting a dramatic, short-lived X-ray flare that was picked up by an X-ray telescope on the International Space Station.

Using optical telescopes in South Africa and Chile, the Southampton astronomers showed that the flare, called XRF111111 as it happened on 11 November, 2011, was located in the Small Magellanic Cloud. These Magellanic Clouds are between 160,000 and 200,000 light years away and are the nearest satellite galaxies to the Milky Way. They are visible to the naked eye from the Southern Hemisphere.

The flare from XRF111111 was so luminous that astronomers initially thought it was likely to be a black hole producing X-rays but further research by Phil and his team revealed that its X-ray temperature was so low that it had to be a white dwarf instead.

White dwarfs are very common, burnt-out cinders of normal stars like the Sun that are typically about one solar mass but are contained in a volume no bigger than Earth.

However, white dwarfs were not considered capable of producing such a huge X-ray flash but the optical observations in South Africa and Chile showed that the white dwarf was orbiting a hot B star -- a normal star about 10 times the mass of our Sun that is much hotter and brighter. This was something that had only been seen twice previously and both times with much lower X-ray luminosities.

Research by Professor Charles and his team revealed that material was probably collecting on the surface of the white dwarf from the B star and eventually underwent runaway thermonuclear burning that was seen on Earth as a nova explosion.

Professor Charles says: "Our observations show that the thermonuclear burning probably caused a shell of matter to be ejected from around the white dwarf and when the shell hit the hot wind of the B star it produced a huge shock leading to the X-ray flash that was seen on the International Space Station.

"We think that this incredible X-ray flash was not due to accretion onto a black hole but was instead due to a nova explosion on a white dwarf that took place close to a hot massive star. This was something that we, as astronomers, have never seen before.

"This surprising result shows that, in the right circumstances, white dwarfs are capable of mimicking black holes, the most luminous objects we know of."

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Journal Reference:

K. L. Li, Albert K. H. Kong, P. A. Charles, Ting-Ni Lu, E. S. Bartlett, M. J. Coe, V. McBride, A. Rajoelimanana, A. Udalski, N. Masetti, Thomas Franzen. A Luminous Be+ White Dwarf Supersoft Source in the Wing of the SMC: MAXI J0158-744. The Astrophysical Journal, 2012; 761 (2): 99 DOI: 10.1088/0004-637X/761/2/99

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Seven primitive galaxies at the dawn of time

Dec. 12, 2012 — Using NASA's Hubble Space Telescope, astronomers have uncovered a previously unseen population of seven primitive galaxies that formed more than 13 billion years ago, when the universe was less than 3 percent of its present age. The deepest images to date from Hubble yield the first statistically robust sample of galaxies that tells how abundant they were close to the era when galaxies first formed.

The results show a smooth decline in the number of galaxies with increasing look-back time to about 450 million years after the big bang. The observations support the idea that galaxies assembled continuously over time and also may have provided enough radiation to reheat, or reionize, the universe a few hundred million years after the big bang.

These pioneering observations blaze a trail for future exploration of this epoch by NASA's next-generation spacecraft, the James Webb Space Telescope. Looking deeper into the universe also means peering farther back in time. The universe is now 13.7 billion years old. The newly discovered galaxies are seen as they looked 350 million to 600 million years after the big bang. Their light is just arriving at Earth now.

The greater depth of the new Hubble images, together with a carefully designed survey strategy, allows this work to go further than previous studies, thereby providing the first reliable census of this epoch, say the researchers. Notably, one of the galaxies may be a distance record breaker, observed 380 million years after the birth of our universe in the big bang, corresponding to a redshift of 11.9.

The results are from an ambitious Hubble survey of an intensively studied patch of sky known as the Ultra Deep Field (UDF). In the new 2012 campaign, called UDF 2012, a team of astronomers led by Richard Ellis of the California Institute of Technology in Pasadena, Calif., used Hubble's Wide Field Camera 3 (WFC3) to peer deeper into space in near infrared light than any previous Hubble observation. The observations were made over a period of six weeks during August and September, and the first scientific results are now appearing in a series of scientific papers. The UDF 2012 team is publicly releasing these unique data, after preparing them for other research groups to use.

Astronomers study the distant universe in near-infrared light because the expansion of space stretches ultraviolet and visible light from galaxies into infrared wavelengths, a phenomenon called "redshift." The more distant a galaxy, the higher its redshift.

A major goal of the new program was to determine how rapidly the number of galaxies increases over time in the early universe. This measure is the key evidence for how quickly galaxies build up their constituent stars.

"Our study has taken the subject forward in two ways," Ellis explained. "First, we have used Hubble to make longer exposures than previously. The added depth is essential to reliably probe the early period of cosmic history. Second, we have used Hubble's available color filters very effectively to more precisely measure galaxy distances."

The team estimated the galaxy distances by studying their colors through a carefully chosen set of four filters at specific near-infrared wavelengths. "We added an additional filter, and undertook much deeper exposures in some filters than in earlier work in order to convincingly reject the possibility that some of our galaxies might be foreground objects," said team member James Dunlop of the Institute for Astronomy, University of Edinburgh.

For galaxies whose light has been shifted to infrared wavelengths, Dunlop said, the intervening hydrogen will have absorbed all of the light that was originally emitted as visible light and most of the light initially released at near-infrared wavelengths. Therefore, these galaxies will not be detected in most of Hubble's filters. They will only be seen in Hubble's longer-wavelength infrared filters, which hold the key to discovering the earliest galaxies.

The results from the UDF 2012 campaign mean there may be many undiscovered galaxies even deeper in space waiting to be uncovered by the Webb telescope. "Although we may have reached back as far as Hubble will see, Hubble has, in a sense, set the stage for Webb," noted team member Anton Koekemoer of the Space Telescope Science Institute in Baltimore, Md., who oversaw the Hubble observations and combined the images. "Our work indicates that there may be a rich field of even earlier galaxies that Webb will be able to study."

Astronomers have long debated whether hot stars in such early galaxies could have provided enough radiation to warm the cold hydrogen that formed soon after the big bang. This process, called "reionization," is thought to have occurred 200 million to a billion years after our universe's birth. This process made the universe transparent to light, allowing astronomers to look far back into time. The galaxies in the new study are seen in this early epoch.

"Observations of the microwave afterglow from the big bang tell us that reionization happened more than about 13 billion years ago," said Brant Robertson of the University of Arizona in Tucson. "Our data confirms that reionization was a drawn-out process occurring over several hundred million years with galaxies slowly building up their stars and chemical elements. There wasn't a single dramatic moment when galaxies formed; it was a gradual process."

The team's finding on the distant galaxy census has been accepted for publication in The Astrophysical Journal Letters.

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