Thursday, November 25, 2010

NASA Funds High School Student Robotics Program

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NASA is providing up to $20 million over the next five years to support a national program to inspire student interest in science, technology and mathematics with a focus on robotic technology.

The funding is part of a cooperative agreement with the Foundation for Inspiration and Recognition of Science and Technology (FIRST), a nonprofit organization in Manchester, N.H. FIRST provides students the opportunity to engage with government, industry and university experts, including those at NASA's Jet Propulsion Laboratory, Pasadena, Calif., for hands-on, realistic exposure to engineering and technical professions.

"This is the largest NASA-funded student program geared toward robotics activities," said NASA Administrator Charles Bolden. "For the next five years, approximately 25,000 students across the country will not only learn from our nation's best and brightest, but also compete and have fun at the same time."

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Wednesday, November 24, 2010

NASA Study Finds Earth's Lakes are Warming

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In the first comprehensive global survey of temperature trends in major lakes, NASA researchers determined Earth's largest lakes have warmed during the past 25 years in response to climate change.

Researchers Philipp Schneider and Simon Hook of NASA's Jet Propulsion Laboratory in Pasadena, Calif., used satellite data to measure the surface temperatures of 167 large lakes worldwide.

They reported an average warming rate of 0.45 degrees Celsius (0.81 degrees Fahrenheit) per decade, with some lakes warming as much as 1 degree Celsius (1.8 degrees Fahrenheit) per decade. The warming trend was global, and the greatest increases were in the mid- to high-latitudes of the Northern Hemisphere.

"Our analysis provides a new, independent data source for assessing the impact of climate change over land around the world," said Schneider, lead author of the study published this week in the journal Geophysical Research Letters. "The results have implications for lake ecosystems, which can be adversely affected by even small water temperature changes."

Small changes in water temperature can result in algal blooms that can make a lake toxic to fish or result in the introduction of non-native species that change the lake's natural ecosystem.

Scientists have long used air temperature measurements taken near Earth's surface to compute warming trends. More recently, scientists have supplemented these measurements with thermal infrared satellite data that can be used to provide a comprehensive, accurate view of how surface temperatures are changing worldwide.

The NASA researchers used thermal infrared imagery from National Oceanic and Atmospheric Administration and European Space Agency satellites. They focused on summer temperatures (July to September in the Northern Hemisphere and January to March in the Southern Hemisphere) because of the difficulty in collecting data in seasons when lakes are ice-covered and/or often hidden by clouds. Only nighttime data were used in the study.

The bodies studied were selected from a global database of lakes and wetlands based on size (typically at least 500 square kilometers – 193 square miles – or larger) or other unique characteristics of scientific merit. The selected lakes also had to have large surface areas located away from shorelines, so land influences did not interfere with the measurements. Satellite lake data were collected from the point farthest from any shoreline.

The largest and most consistent area of warming was northern Europe. The warming trend was slightly weaker in southeastern Europe, around the Black and Caspian seas and Kazakhstan. The trends increased slightly farther east in Siberia, Mongolia and northern China.

In North America, trends were slightly higher in the southwest United States than in the Great Lakes region. Warming was weaker in the tropics and in the mid-latitudes of the Southern Hemisphere. The results were consistent with the expected changes associated with global warming.

The satellite temperature trends largely agreed with trends measured by nine buoys in the Great Lakes, Earth's largest group of freshwater lakes in terms of total surface area and volume.

The lake temperature trends were also in agreement with independent surface air temperature data from NASA's Goddard Institute for Space Studies in New York. In certain regions, such as the Great Lakes and northern Europe, water bodies appear to be warming more quickly than surrounding air temperature.

For more information about NASA and agency programs, visit: http://www.nasa.gov .

Tuesday, November 23, 2010

Spitzer Sees Shrouded Burst of Stars

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Astronomers using NASA's Spitzer Space Telescope have found a stunning burst of star formation that beams out as much infrared light as an entire galaxy. The collision of two spiral galaxies has triggered this explosion, which is cloaked by dust that renders its stars nearly invisible in other wavelengths of light.

The starburst newly revealed by Spitzer stands as the most luminous ever seen taking place away from the centers, or nuclei, of merging parent galaxies. It blazes ten times brighter than the nearby Universe's previous most famous "off-nuclear starburst" that gleams in another galactic smashup known as the Antennae Galaxy.

The new findings show that galaxy mergers can pack a real star-making wallop far from the respective galactic centers, where star-forming dust and gases typically pool.

"This discovery proves that merging galaxies can generate powerful starbursts outside of the centers of the parent galaxies," says Hanae Inami, first author of a paper detailing the results in the July issue of The Astronomical Journal. Inami is a graduate student at The Graduate University for Advanced Studies in Japan and the Spitzer Science Center at the California Institute of Technology. She adds: "The infrared light emission of the starburst dominates its host galaxy and rivals that of the most luminous galaxies we see that are relatively close to our home, the Milky Way."

"No matter how you slice it, this starburst is one of the most luminous objects in the local Universe," agrees Lee Armus, second author of the paper and a senior research astronomer also at the Spitzer Science Center.
A dazzling galactic dust-up

Inami, Armus and their colleagues spotted the buried starburst with Spitzer in the interacting galaxies known as II Zw 096. This galactic train wreck - located around 500 million light years away in the constellation Delphinus (the Dolphin) - will continue to unfold for a few hundred million years. Gravitational forces have already dissolved the once-pinwheel shape of one of II Zw 096's pair of merging galaxies.

The ultra-bright starburst region spans 700 light-years or so - just a tiny portion of II Zw 096, which streams across some 50,000 to 60,000 light-years - yet it blasts out 80 percent of the infrared light from this galactic tumult. Based on Spitzer data, researchers estimate the starburst is cranking out stars at the breakneck pace of around 100 solar masses, or masses of our Sun, per year.

The prodigious energy output of this starburst in a decentralized location as revealed in the infrared has surprised the Spitzer researchers. The new observations go to show how the notion of a cosmic object's nature can change tremendously when viewed at different wavelengths of light. In this way, the shapes and dynamics of distant, harder-to-study galactic mergers could turn out to be a good deal more complex than current observations over a narrow range of wavelengths imply.

"Most of the far-infrared emission in II Zw 096, and hence most of the power, is coming from a region that is not associated with the centers of the merging galaxies," Inami explains. "This suggests that the appearances and interactions of distant, early galaxies during epochs when mergers were much more common than today in the Universe might be more complicated than we think."
A fleeting, perhaps prophetic vista?

In galaxy mergers, individual stars rarely slam into one another because of the vast distances separating them; even in the comparatively crowded central hubs of spiral galaxies, trillions of kilometers still often yawn between the stars.

But giant, diffuse clouds of gas and dust in galaxies do crash together - passing through each other somewhat like ocean waves - and in turn spur the gravitational collapse of dense pockets of matter into new stars. These young, hot stars shine intensely in the energetic ultraviolet part of the spectrum. In the case of II Zw 096, however, a thick shroud of gas and dust still surrounds this stellar brood. The blanket of material absorbs the stars' light and re-radiates it in the lower-energy, infrared wavelengths that gleam clear through the dust to Spitzer's camera.

Astronomers were lucky to capture this transient phase in the evolution of the starburst and of the daughter galaxy that will eventually coalesce out of the collision. "Spitzer has allowed us to see the fireworks before all the gas and dust has cleared away, giving us a preview of the exciting new galaxy being built under the blanket," Inami says.

Merging galaxies such as II Zw 096 also offer a sneak peek at the fate of our Milky Way in some 4.5 billion years when it is expected to plow into its nearest large galactic neighbor, the Andromeda Galaxy. Off-nuclear starbursts such as that in II Zw 096 and the Antennae Galaxy could occur in the vicinity of our Solar System, perhaps, which is located about two-thirds of the way out from the Milky Way's glowing, bulging center.

"This kind of dramatic thing happening in II Zw 096 could happen to the Milky Way and Andromeda when they meet in the far future," says Inami.

Friday, November 19, 2010

NASA Mars Rover Images Honor Apollo 12

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NASA's Mars Exploration Rover Opportunity has visited and photographed two craters informally named for the spacecraft that carried men to the moon 41 years ago this week.

Opportunity drove past "Yankee Clipper" crater on Nov. 4 and reached "Intrepid crater" on Nov. 9. For NASA's Apollo 12, the second mission to put humans onto the moon, the command and service module was called Yankee Clipper, piloted by Dick Gordon, and the lunar module was named Intrepid, piloted by Alan Bean and commanded by the late Pete Conrad. The Intrepid landed on the moon with Bean and Conrad on Nov. 19, 1969, while Yankee Clipper orbited overhead. Their landing came a mere four months after Apollo 11's first lunar landing.

This week, Bean wrote to the Mars Exploration Rover team: "I just talked with Dick Gordon about the wonderful honor you have bestowed upon our Apollo 12 spacecraft. Forty-one years ago today, we were approaching the moon in Yankee Clipper with Intrepid in tow. We were excited to have the opportunity to perform some important exploration of a place in the universe other than planet Earth where humans had not gone before. We were anxious to give it our best effort. You and your team have that same opportunity. Give it your best effort."

Rover science team member James Rice, of NASA's Goddard Space Flight Center, Greenbelt, Md., suggested using the Apollo 12 names. He was applying the rover team's convention of using names of historic ships of exploration for the informal names of craters that Opportunity sees in the Meridian Planum region of Mars.

"The Apollo missions were so inspiring when I was young, I remember all the dates. When we were approaching these craters, I realized we were getting close to the Nov. 19 anniversary for Apollo 12," Rice said. He sent Bean and Gordon photographs that Opportunity took of the two craters.

The images are available online at http://photojournal.jpl.nasa.gov/catalog/PIA13593 and http://photojournal.jpl.nasa.gov/catalog/PIA13596. Intrepid crater is about 20 meters (66 feet) in diameter. Yankee Clipper crater is about half that width.

After a two-day stop to photograph the rocks exposed at Intrepid, Opportunity continued on a long-term trek toward Endeavour crater, a highly eroded crater about 1,000 times wider than Intrepid. Endeavour's name comes from the ship of James Cook's first Pacific voyage.

During a drive of 116.9 meters (383.5 feet) on Nov. 14, Opportunity's "odometer" passed 25 kilometers (15.53 miles). That is more than 40 times the driving-distance goal set for Opportunity to accomplish during its original three-month prime mission in 2004.

Mars Exploration Project Manager John Callas, of NASA's Jet Propulsion Laboratory, Pasadena, Calif., said, "Importantly, it's not how far the rovers have gone but how much exploration and science discovery they have accomplished on behalf of all humankind."

At the beginning of Opportunity's mission, the rover landed inside "Eagle crater," about the same size as Intrepid crater. The team's name for that landing-site crater paid tribute to the lunar module of Apollo 11, the first human landing on the moon. Opportunity spent two months inside Eagle crater, where it found multiple lines of evidence for a wet environment in the area's ancient past.

The rover team is checking regularly for Opportunity's twin, Spirit, in case the increasing daily solar energy available at Spirit's location enables the rover to reawaken and resume communication. No signal from Spirit has been received since March 22. Spring began last week in the southern hemisphere of Mars.

JPL, a division of the California Institute of Technology in Pasadena, manages the Mars Exploration Rovers for the NASA Science Mission Directorate, Washington. For more information about the rovers, visit: http://www.nasa.gov/rovers.

Thursday, November 18, 2010

Camera on Curiosity's Arm will Magnify Clues in Rocks

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NASA's next Mars rover, Curiosity, will wield an arm-mounted magnifying camera similar to one on the Mars Rover Opportunity, which promptly demonstrated its importance for reading environmental history from rocks at its landing site in 2004.

Within a few weeks after the landing, that camera at the end of Opportunity's arm revealed details of small spheres embedded in the rocks, hollows where crystals had dissolved, and fine layering shaped like smiles. These details all provided information about the site's wet past.

The camera installed on the end of Curiosity's arm this month is the Mars Hand Lens Imager, or MAHLI. Its work will include the same type of close-up inspections accomplished by the comparable camera on Opportunity, but MAHLI has significantly greater capabilities: full-color photography, adjustable focus, lights, and even video. Also, it sits on a longer arm, one that can hold MAHLI up higher than the cameras on the rover's mast. MAHLI will use those capabilities as one of 10 science instruments to study the area of Mars where NASA's Mars Science Laboratory mission lands Curiosity in August 2012.

The Mars Hand Lens Imager takes its name from the magnifying tool that every field geologist carries. Ken Edgett of Malin Space Science Systems, San Diego, is the principal investigator for the instrument. He said, "When you’re out in the field and you want to get a quick idea what minerals are in a rock, you pick up the rock in one hand and hold your hand lens in the other hand. You look through the lens at the colors, the crystals, the cleavage planes: features that help you diagnose what minerals you see.

"If it's a sedimentary rock, such as the sandstone you see at Arches National Park in Utah, or shale -- which is basically petrified mud -- like in the Painted Desert in Arizona, you use the hand lens not just to see what minerals are in it but also the sizes and shapes of the grains in the rock. You also look at the fine-scale layering in the rock to get an idea of the sequence of events. Sedimentary rocks record past events and environments."

While other instruments on Curiosity will provide more information about what minerals are in rocks, the Mars Hand Lens Imager will play an important role in reading the environmental history recorded in sedimentary rocks. The mission's science team will use the instruments to assess whether the selected landing area has had environmental conditions favorable for life and for preserving evidence about whether life existed.

The team currently assembling and testing Curiosity and other parts of the Mars Science Laboratory spacecraft at NASA's Jet Propulsion Laboratory, Pasadena, Calif., is continuing tests of MAHLI this month, now that the camera is mounted beside other tools on the robotic arm. The spacecraft will launch from Florida between Nov. 25 and Dec. 18, 2011.

Edgett led the preparation in early 2004 of a proposal to include MAHLI in the Mars Science Laboratory's payload. During those same months, the camera on Opportunity's arm -- that mission's Microscopic Imager -- was demonstrating the potential value of a successor, and generating ideas for improvements. Opportunity's Microscopic Imager has a fixed focus. To get targets in focus, it always needs to be placed the same distance from the target, recording a view of an area 3 centimeters (1.2 inches) across. To view a larger area, the camera takes multiple images, sometimes more than a dozen, each requiring a repositioning of Opportunity's arm.

"When I was writing the proposal, the Microscopic Imager took about 40 images for a mosaic of one rock," Edgett said. "That's where the idea came from to make the focus adjustable. With adjustable focus, the science team has more flexibility for trade-offs among the rover's resources, such as power, time, data storage and data downlink. For example, the camera could take one or two images from farther away to cover a larger area, then go in and sample selected parts in higher resolution from closer up."

MAHLI can focus on targets as close as about 21 millimeters (0.8 inch) and as distant as the horizon or farther. JPL's Ashwin Vasavada, deputy project scientist for the Mars Science Laboratory, said, "MAHLI is really a fully functional camera that happens to be on the end of the arm. The close-up capability is its specialty, but it will also be able to take images or videos from many viewpoints inaccessible to the cameras on the mast, such as up high, down low, under the rover and on the rover deck. Think of it like a hand-held camera with a macro lens, one that you could use for taking pictures of the Grand Canyon, of yourself, or of a bumblebee on a flower."

Edgett is looking forward to what the camera will reveal in rock textures. "Just like larger rocks in a river, grains of sand carried in a stream get rounded from bouncing around and colliding with each other," he said. "If you look at a sandstone with a hand lens and see rounded grains, that tells you they came from a distance. If they are more angular, they didn't come as far before they were deposited in the sediment that became the rock. Where an impact excavated a crater, particles of the material ejected from the crater would be very angular.

"When you're talking about ancient rocks as clues for assessing habitability," he continued, "you're talking about the environments the sediments were deposited in -- whether a lake, a desert, an ice field. Also, what cemented the particles together to become rocks, and what changes have affected the rock after the sediments were deposited? All these things are relevant to whether an environment was favorable for life and also whether it was favorable for preserving the record of that life. Earth is a planet teeming with life, but most rocks have not preserved ancient organisms; Mars will be even more challenging than Earth in this sense."

Edgett says he is eager to see an additional image from this camera besides the details of rock textures. With the arm extended upwards, the camera can look down at the rover for a dramatic self-portrait on Mars. But as for the most important image the Mars Hand Lens Imager will take: "That will be something that surprises us, something we're not expecting."

Mars Science Laboratory is managed by NASA’s Jet Propulsion Laboratory, Pasadena, Calif. JPL also manages the Mars Exploration Rovers Spirit and Opportunity. JPL is a division of the California Institute of Technology in Pasadena.
More information about NASA's Mars Science Laboratory is at: http://www.nasa.gov/msl .

Wednesday, November 17, 2010

Shedding 'Bent' Light on Dark Matter

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Astronomers using NASA's Hubble Space Telescope took advantage of a giant cosmic magnifying glass to create one of the sharpest and most detailed maps of dark matter in the universe. Dark matter is an invisible and unknown substance that makes up the bulk of the universe's mass. Astronomer Dan Coe led the research while working at NASA's Jet Propulsion Laboratory in Pasadena, Calif.; he is currently with the Space Telescope Science Institute in Baltimore, Md.

The astronomers used Hubble to chart the invisible matter in the massive galaxy cluster Abell 1689, located 2.2 billion light-years away. The cluster's gravity, the majority of which comes from dark matter, acts like a cosmic magnifying glass, bending and amplifying the light from distant galaxies behind it. This effect, called gravitational lensing, produces multiple, warped, and greatly magnified images of those galaxies, like the view in a funhouse mirror. By studying the distorted images, astronomers estimated the amount of dark matter within the cluster.

The new dark matter observations may yield new insights into the role of dark energy in the universe's early formative years. A mysterious property of space, dark energy fights against the gravitational pull of dark matter. The new results suggest that galaxy clusters may have formed earlier than expected, before the push of dark energy inhibited their growth. Dark energy pushes galaxies apart from one another by stretching the space between them, suppressing the formation of giant structures called galaxy clusters. One way astronomers can probe this primeval tug-of-war is by mapping the distribution of dark matter in clusters.

Read the full story at http://hubblesite.org/newscenter/archive/releases/2010/37/full/ .

The California Institute of Technology in Pasadena manages JPL for NASA.