NASA Study Sheds Light on Ozone Hole Chemistry

A new NASA study of Earth's polar ozone layer reinforces scientists' understanding of how human-produced chlorine chemicals involved in the destruction of ozone interact with each other.

A team of scientists led by Michelle Santee of NASA's Jet Propulsion Laboratory, Pasadena, Calif., examined how nighttime temperatures affect chlorine monoxide, a key chemical involved in ozone destruction. Combining NASA satellite measurements with a state-of-the-art chemical model, they found this relationship to be more consistent with recent laboratory work than with some older laboratory and field observational data. This verification is important, because scientists have not been able to conduct appropriate laboratory experiments relevant to understanding how polar chlorine monoxide behaves at night at the lowest temperatures of the stratosphere, Earth's second lowest atmospheric layer.

Santee and her team published their findings this month in the Proceedings of the National Academy of Sciences. The data came from the Microwave Limb Sounder instrument on NASA's Aura satellite.

"Our comprehensive study uses multiple years of Arctic and Antarctic satellite observations to quantify the nighttime balance of ozone-destroying chlorine chemical compounds," said Santee. "By gaining a better knowledge of this balance, scientists will be able to make more accurate predictions of polar ozone loss, especially in twilight and in the Arctic, where conditions are often only marginally favorable for ozone destruction."

At night, chlorine monoxide molecules combine to form chlorine peroxide, and the balance between these two chemicals is highly temperature-sensitive. Studying this balance quantitatively is challenging. Previous studies in the laboratory and using aircraft and satellites had found significantly different degrees of balance. The Microwave Limb Sounder's very large number of measurements has quantified this balance far better than before.

The new research contributes to scientific understanding of the phenomenon more commonly known as the "ozone hole." Each year in late winter and early spring in the southern hemisphere, chlorine and bromine from human-produced compounds cause the nearly total destruction of ozone in Earth's stratosphere in a layer about 20 kilometers (12 miles) above Antarctica. These source gases that are responsible for the greatest destruction of the ozone layer are now declining in response to the 1985 Montreal Protocol and its amendments.

Since its launch in 2004, the Microwave Limb Sounder has monitored most of the polar regions of both hemispheres daily, compiling tens of thousands of measurements of nighttime chlorine monoxide levels, along with various other chemicals, including ozone. These data are allowing scientists to test their understanding of chlorine-related chemistry on an unprecedented scale.

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Cassini and Amateurs Chase Storm on Saturn

Cassini and Amateurs

With the help of amateur astronomers, the composite infrared spectrometer instrument aboard NASA's Cassini spacecraft has taken its first look at a massive blizzard in Saturn's atmosphere. The instrument collected the most detailed data to date of temperatures and gas distribution in that planet's storms.

The data showed a large, turbulent storm, dredging up loads of material from the deep atmosphere and covering an area at least five times larger than the biggest blizzard in this year's Washington, D.C.-area storm front nicknamed "Snowmageddon."

"We were so excited to get a heads-up from the amateurs," said Gordon Bjoraker, a composite infrared spectrometer team member based at NASA's Goddard Space Flight Center in Greenbelt, Md. Normally, he said, "Data from the storm cell would have been averaged out."

Cassini's radio and plasma wave instrument and imaging cameras have been tracking thunder and lightning storms on Saturn for years in a band around Saturn's mid-latitudes nicknamed "storm alley." But storms can come and go on a time scale of weeks, while Cassini's imaging and spectrometer observations have to be locked in place months in advance.

The radio and plasma wave instrument regularly picks up electrostatic discharges associated with the storms, so team members have been sending periodic tips to amateur astronomers, who can quickly go to their backyard telescopes and try to see the bright convective storm clouds. Amateur astronomers including Anthony Wesley, Trevor Barry and Christopher Go got one of those notices in February and were able to take dozens of pictures over the next several weeks.

In late March, Wesley, an amateur astronomer from Australia who was actually the first person to detect the new dark spot caused by an impact on Jupiter last summer, sent Cassini scientists an e-mail with a picture of the storm.

"I wanted to be sure that images like these were being seen by the Cassini team just in case this was something of interest to be imaged directly by Cassini or the Hubble Space Telescope," Wesley wrote.

Cassini scientists eagerly pored through the images, including a picture of the storm at its peak on March 13 by Go, who lives in the Philippines.

By a stroke of luck, the composite infrared spectrometer happened to be targeting the latitude of the storms. The instrument's scientists knew there could be storms there, but didn't know when they might be active.

Data obtained by the spectrometer on March 25 and 26 showed larger than expected amounts of phosphine, a gas typically found in Saturn's deep atmosphere and an indicator that powerful currents were dredging material upward into the upper troposphere. The spectrometer data also showed another signature of the storm: the tropopause, the dividing line between the serene stratosphere and the lower, churning troposphere, was about 0.5 Kelvin (1 degree Fahrenheit) colder in the storm cell than in neighboring areas.

"A balloonist floating about 100 kilometers down from the bottom of Saturn's calm stratosphere would experience an ammonia-ice blizzard with the intensity of Snowmageddon," said Brigette Hesman, a composite infrared spectrometer team member who is an assistant research scientist at the University of Maryland. "These blizzards appear to be powered by violent storms deeper down - perhaps another 100 to 200 kilometers down - where lightning has been observed and the clouds are made of water and ammonia."

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 mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The composite infrared spectrometer team is based at NASA's Goddard Space Flight Center, Greenbelt, Md., where the instrument was built.

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Scientists Say Ice Lurks In Asteroid's Cold Heart

Scientists using a NASA funded telescope have detected water-ice and carbon-based organic compounds on the surface of an asteroid. The cold hard facts of the discovery of the frosty mixture on one of the asteroid belt's largest occupants, suggests that some asteroids, along with their celestial brethren, comets, were the water carriers for a primordial Earth. The research is published in today's issue of the journal Nature.

"For a long time the thinking was that you couldn't find a cup's worth of water in the entire asteroid belt," said Don Yeomans, manager of NASA's Near-Earth Object Program Office at the Jet Propulsion Laboratory in Pasadena, Calif. "Today we know you not only could quench your thirst, but you just might be able to fill up every pool on Earth - and then some."

The discovery is a result of six years of observing asteroid 24 Themis by astronomer Andrew Rivkin of the Johns Hopkins University Applied Physics Laboratory in Laurel, Maryland. Rivkin, along with Joshua Emery, of the University of Tennessee in Knoxville, employed the NASA Infrared Telescope Facility to take measurements of the asteroid on seven separate occasions beginning in 2002. Buried in their compiled data was the consistent infrared signature of water ice and carbon-based organic materials.

The study's findings are particularly surprising because it was believed that Themis, orbiting the sun at "only" 479 million kilometers (297 million miles), was too close to the solar system's fiery heat source to carry water ice left over from the solar system's origin 4.6 billion years ago.

Now, the astronomical community knows better. The research could help re-write the book on the solar system's formation and the nature of asteroids.

"This is exciting because it provides us a better understanding about our past - and our possible future," said Yeomans. "This research indicates that not only could asteroids be possible sources of raw materials, but they could be the fueling stations and watering holes for future interplanetary exploration."

Rivkin and Emory's findings were independently confirmed by a team led by Humberto Campins at the University of Central Florida in Orlando.

NASA detects, tracks and characterizes asteroids and comets passing close to Earth using both ground- and space-based telescopes. The Near-Earth Object Observations Program, commonly called "Spaceguard," discovers these objects, characterizes a subset of them, and plots their orbits to determine if any could be potentially hazardous to our planet.

JPL manages the Near-Earth Object Program Office for NASA's Science Mission Directorate in Washington. JPL is a division of the California Institute of Technology in Pasadena.

-----------------------------

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Planck Sees a Cold and Stormy Orion

The big hunter in the sky is seen in a new light by Planck, a European Space Agency mission with significant NASA participation. The long-wavelength image shows most of the constellation Orion, highlighting turbid clouds of cold material, where new stars are being stirred into existence.

The Planck mission is busy surveying the whole sky at longer wavelengths of light than we can see with our eyes, ranging from infrared to even longer-wavelength microwaves. It is collecting ancient light from when the universe was very young, less than half a million years old, telling us about the birth and fate of our universe. In the process, the mission is gathering data on our Milky Way galaxy that astronomers are using to see through cold pools of gas and dust, which block visible-light views of star formation.

The new image is online at: http://www.nasa.gov/mission_pages/planck/planckorion20100426.html. It shows one such region in our Milky Way, where stars are actively bursting to life. The much-photographed Orion nebula is the bright spot to the lower center. The bright spot to the right of center is around the Horsehead Nebula, so called because at high magnifications a pillar of dust resembles a horse's head. The whole view covers a square patch of sky equivalent to 26 by 26 moons.

"Because Planck is mapping the whole sky, we can capture mosaics of huge regions of the Milky Way," said Charles Lawrence, the NASA project scientist for Planck at NASA's Jet Propulsion Laboratory in Pasadena, Calif. "We are seeing the coldest material in star-forming regions, where stars are at the very earliest stages of formation."

The giant red arc of Barnard's Loop is thought to be the blast wave from a star that blew up inside the region about two million years ago. The bubble it created is now about 300 light-years across.

The picture shows light resulting from two different types of sources. At the lowest frequencies, Planck primarily maps emission from ionized gas heated by newly formed hot stars. At higher frequencies, Planck maps the meager heat emitted by extremely cold dust. This can reveal the coldest cores in the clouds, which are approaching the final stages of collapse, before they are reborn as full-fledged stars.

Another new image from Planck shows a similar, yet less vigorous star-forming area called Perseus. It is online at: http://www.nasa.gov/mission_pages/planck/planckperseus20100426.html .

Planck is a European Space Agency mission, with significant participation from NASA. NASA's Planck Project Office is based at JPL. JPL contributed mission-enabling technology for both of Planck's science instruments. European, Canadian, U.S. and NASA Planck scientists will work together to analyze the Planck data. More information is online at http://www.nasa.gov/planck and http://www.esa.int/planck .

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Cassini Measures Tug of Enceladus

NASA's Cassini spacecraft will be gliding low over Saturn's moon Enceladus for a gravity experiment designed to probe the moon's interior composition. The flyby, which will take Cassini through the water-rich plume flaring out from Enceladus's south polar region, will occur on April 27 Pacific time and April 28 UTC. At closest approach, Cassini will be flying about 100 kilometers (60 miles) above the moon's surface.

Cassini's scientists plan to use the radio science instrument to measure the gravitational pull of Enceladus against the steady radio link to NASA's Deep Space Network on Earth. Detecting any wiggle will help scientists understand what is under the famous "tiger stripe" fractures that spew water vapor and organic particles from the south polar region. Is it an ocean, a pond or a great salt lake?

The experiment will also help scientists find out if the sub-surface south polar region resembles a lava lamp. Scientists have hypothesized that a bubble of warmer ice periodically moves up to the crust and repaves it, explaining the quirky heat behavior and intriguing surface features.

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 in Pasadena, manages the Cassini-Huygens mission for NASA's Science Mission Directorate in Washington. The Cassini orbiter was designed, developed and assembled at JPL.

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'This Planet Tastes Funny,' According to Spitzer

NASA's Spitzer Space Telescope has discovered something odd about a distant planet -- it lacks methane, an ingredient common to many of the planets in our solar system.

"It's a big puzzle," said Kevin Stevenson, a planetary sciences graduate student at the University of Central Florida in Orlando, lead author of a study appearing tomorrow, April 22 in the journal Nature. "Models tell us that the carbon in this planet should be in the form of methane. Theorists are going to be quite busy trying to figure this one out."

The discovery brings astronomers one step closer to probing the atmospheres of distant planets the size of Earth. The methane-free planet, called GJ 436b, is about the size of Neptune, making it the smallest distant planet that any telescope has successfully "tasted," or analyzed. Eventually, a larger space telescope could use the same kind of technique to search smaller, Earth-like worlds for methane and other chemical signs of life, such as water, oxygen and carbon dioxide.

"Ultimately, we want to find biosignatures on a small, rocky world. Oxygen, especially with even a little methane, would tell us that we humans might not be alone," said Stevenson.

"In this case, we expected to find methane not because of the presence of life, but because of the planet's chemistry. This type of planet should have cooked up methane. It's like dipping bread into beaten eggs, frying it, and getting oatmeal in the end," said Joseph Harrington of the University of Central Florida, the principal investigator of the research.

Methane is present on our life-bearing planet, manufactured primarily by microbes living in cows and soaking in waterlogged rice fields. All of the giant planets in our solar system have methane too, despite their lack of cows. Neptune is blue because of this chemical, which absorbs red light. Methane is a common ingredient of relatively cool bodies, including "failed" stars, which are called brown dwarfs.

In fact, any world with the common atmospheric mix of hydrogen, carbon and oxygen, and a temperature up to 1,000 Kelvin (1,340 degrees Fahrenheit) is expected to have a large amount of methane and a small amount of carbon monoxide. The carbon should "prefer" to be in the form of methane at these temperatures.

At 800 Kelvin (or 980 degrees Fahrenheit), GJ 436b is supposed to have abundant methane and little carbon monoxide. Spitzer observations have shown the opposite. The space telescope has captured the planet's light in six infrared wavelengths, showing evidence for carbon monoxide but not methane.

"We're scratching our heads," said Harrington. "But what this does tell us is that there is room for improvement in our models. Now we have actual data on faraway planets that will teach us what's really going on in their atmospheres."

GJ 436b is located 33 light-years away in the constellation Leo, the Lion. It rides in a tight, 2.64-day orbit around its small star, an "M-dwarf" much cooler than our sun. The planet transits, or crosses in front of, its star as viewed from Earth.

Spitzer was able to detect the faint glow of GJ 436b by watching it slip behind its star, an event called a secondary eclipse. As the planet disappears, the total light observed from the star system drops -- this drop is then measured to find the brightness of the planet at various wavelengths. The technique, first pioneered by Spitzer in 2005, has since been used to measure atmospheric components of several Jupiter-sized exoplanets, the so-called "hot Jupiters," and now the Neptune-sized GJ 436b.

"The Spitzer technique is being pushed to smaller, cooler planets more like our Earth than the previously studied hot Jupiters," said Charles Beichman, director of NASA's Exoplanet Science Institute at NASA's Jet Propulsion Laboratory and the California Institute of Technology, both in Pasadena, Calif. "In coming years, we can expect that a space telescope could characterize the atmosphere of a rocky planet a few times the size of the Earth. Such a planet might show signposts of life."

This research was performed before Spitzer ran out of its liquid coolant in May 2009, officially beginning its "warm" mission.

Other authors include: Sarah Nymeyer, William C. Bowman, Ryan A. Hardy and Nate B. Lust from the University of Central Florida; Nikku Madhusudhan and Sara Seager of the Massachusetts Institute of Technology, Cambridge; Drake Deming of NASA's Goddard Space Flight Center, Greenbelt, Md.; and Emily Rauscher of Columbia University, New York.

JPL manages the Spitzer Space Telescope mission for NASA's Science Mission Directorate, Washington. Science operations are conducted at the Spitzer Science Center at Caltech. Caltech manages JPL for NASA. For more information about Spitzer, visit http://www.spitzer.caltech.edu/spitzer and http://www.nasa.gov/spitzer.

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NASA Satellite Eyes Iceland Volcano Cauldron

On Saturday, April 17, 2010, the Hyperion instrument onboard NASA's Earth Observing-1 (EO-1) spacecraft obtained this pair of images of the continuing eruption of Iceland's Eyjafjallajökull volcano. In the left-hand image, created from visible wavelengths, new black ash deposits are visible on the ground, as well as nearby brilliant unsullied ice and snow and the volcano's brown, billowing plume. The plume's dark color reflects its large ash content. These fine particles of pulverized rock are carried high into the atmosphere, where they create a hazard for aviation and are carried long distances by the prevailing winds.

In contrast, the false-color, infrared image at the right reveals the intense thermal emissions (at least 60 megawatts, or 60 million watts) emanating from the vent at the base of the massive plume. This thermal emission, equivalent to the energy consumption of 60,000 homes, represents only a small proportion of the total energy being released by the volcano as its molten lava interacts violently with ice and water. Each image covers an area measuring 7.7 kilometers (4.8 miles) wide, and has a resolution of 30 meters (98 feet) per pixel. The vertical direction is north-northeast.

The EO-1 spacecraft is managed by NASA's Goddard Space Flight Center, Greenbelt, Md. EO-1 is the satellite remote-sensing asset used by the Volcano Sensor Web developed by NASA's Jet Propulsion Laboratory, Pasadena, Calif., which is being used to monitor this, and other, volcanic eruptions around the world.

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'This Planet Tastes Funny,' According to Spitzer

NASA's Spitzer Space Telescope has discovered something odd about a distant planet -- it lacks methane, an ingredient common to many of the planets in our solar system.

"It's a big puzzle," said Kevin Stevenson, a planetary sciences graduate student at the University of Central Florida in Orlando, lead author of a study appearing tomorrow, April 22 in the journal Nature. "Models tell us that the carbon in this planet should be in the form of methane. Theorists are going to be quite busy trying to figure this one out."

The discovery brings astronomers one step closer to probing the atmospheres of distant planets the size of Earth. The methane-free planet, called GJ 436b, is about the size of Neptune, making it the smallest distant planet that any telescope has successfully "tasted," or analyzed. Eventually, a larger space telescope could use the same kind of technique to search smaller, Earth-like worlds for methane and other chemical signs of life, such as water, oxygen and carbon dioxide.

"Ultimately, we want to find biosignatures on a small, rocky world. Oxygen, especially with even a little methane, would tell us that we humans might not be alone," said Stevenson.

"In this case, we expected to find methane not because of the presence of life, but because of the planet's chemistry. This type of planet should have cooked up methane. It's like dipping bread into beaten eggs, frying it, and getting oatmeal in the end," said Joseph Harrington of the University of Central Florida, the principal investigator of the research.

Methane is present on our life-bearing planet, manufactured primarily by microbes living in cows and soaking in waterlogged rice fields. All of the giant planets in our solar system have methane too, despite their lack of cows. Neptune is blue because of this chemical, which absorbs red light. Methane is a common ingredient of relatively cool bodies, including "failed" stars, which are called brown dwarfs.

In fact, any world with the common atmospheric mix of hydrogen, carbon and oxygen, and a temperature up to 1,000 Kelvin (1,340 degrees Fahrenheit) is expected to have a large amount of methane and a small amount of carbon monoxide. The carbon should "prefer" to be in the form of methane at these temperatures.

At 800 Kelvin (or 980 degrees Fahrenheit), GJ 436b is supposed to have abundant methane and little carbon monoxide. Spitzer observations have shown the opposite. The space telescope has captured the planet's light in six infrared wavelengths, showing evidence for carbon monoxide but not methane.

"We're scratching our heads," said Harrington. "But what this does tell us is that there is room for improvement in our models. Now we have actual data on faraway planets that will teach us what's really going on in their atmospheres."

GJ 436b is located 33 light-years away in the constellation Leo, the Lion. It rides in a tight, 2.64-day orbit around its small star, an "M-dwarf" much cooler than our sun. The planet transits, or crosses in front of, its star as viewed from Earth.

Spitzer was able to detect the faint glow of GJ 436b by watching it slip behind its star, an event called a secondary eclipse. As the planet disappears, the total light observed from the star system drops -- this drop is then measured to find the brightness of the planet at various wavelengths. The technique, first pioneered by Spitzer in 2005, has since been used to measure atmospheric components of several Jupiter-sized exoplanets, the so-called "hot Jupiters," and now the Neptune-sized GJ 436b.

"The Spitzer technique is being pushed to smaller, cooler planets more like our Earth than the previously studied hot Jupiters," said Charles Beichman, director of NASA's Exoplanet Science Institute at NASA's Jet Propulsion Laboratory and the California Institute of Technology, both in Pasadena, Calif. "In coming years, we can expect that a space telescope could characterize the atmosphere of a rocky planet a few times the size of the Earth. Such a planet might show signposts of life."

This research was performed before Spitzer ran out of its liquid coolant in May 2009, officially beginning its "warm" mission.

Other authors include: Sarah Nymeyer, William C. Bowman, Ryan A. Hardy and Nate B. Lust from the University of Central Florida; Nikku Madhusudhan and Sara Seager of the Massachusetts Institute of Technology, Cambridge; Drake Deming of NASA's Goddard Space Flight Center, Greenbelt, Md.; and Emily Rauscher of Columbia University, New York.

JPL manages the Spitzer Space Telescope mission for NASA's Science Mission Directorate, Washington. Science operations are conducted at the Spitzer Science Center at Caltech. Caltech manages JPL for NASA. For more information about Spitzer, visit http://www.spitzer.caltech.edu/spitzer and http://www.nasa.gov/spitzer.

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NASA Celebrates 40th Anniversary of Earth Day

NASA centers across the nation, including the Jet Propulsion Laboratory in Pasadena, Calif., invite journalists and the public to see and hear about the agency's contributions to exploring and protecting our home planet during this year's Earth Day celebrations. A highlight of this year's activities is a weeklong series of exhibits and talks on the National Mall in Washington.

Begun in 1970, Earth Day is the annual celebration of the environment and a time to assess work still needed to protect the natural resources of our planet. NASA maintains the world's largest contingent of dedicated Earth scientists and engineers in leading and assisting other agencies in preserving the planet's environment.

For a comprehensive listing of NASA's Earth Day activities, visit: http://www.nasa.gov/earthday.

All times are local. NASA center events include:

NASA Headquarters, Washington
Sat., April 17 through Sun., April 25 (11 a.m.-5 p.m. EDT) -- NASA is participating in the Earth Day Celebration on the National Mall organized by the Earth Day Network. The NASA Village, adjacent to the Smithsonian Metro entrance on the Mall, will feature exhibits, presentations and opportunities to meet NASA Earth scientists throughout the week.

Jet Propulsion Laboratory, Pasadena, Calif.
Thurs., April 22 (10-11 a.m. PDT) -- A live, text-based Earth Day Web chat geared toward students in third through eighth grades will feature Mike Gunson, project scientist for NASA's Orbiting Carbon Observatory-2 mission, who will answer questions about how NASA is studying Earth's climate.

Sat. and Sun., April 24-25 (9 a.m.-5 p.m. PDT) -- JPL will join the Earth Day celebration at the Aquarium of the Pacific in Long Beach, Calif. The event will include exhibits and handouts on NASA's Earth science research.

Ames Research Center, Moffett Field, Calif.
Mon., April 19 (1-8 p.m. PDT) -- Reporters and the public are invited to a Green Earth Forum at the Ames Exploration Center to listen to NASA scientists discuss their research and applications projects.

Dryden Flight Research Center, Edwards, Calif.
Wed., April 28 (10 a.m.-2 p.m. PDT) -- Highlights include exhibits and displays from a variety of environmental agencies, public utilities, conservation groups and businesses, and an opportunity to recycle personal electronics.

Glenn Research Center, Cleveland
Sun., April 18 (10 a.m.-5 p.m. EDT) -- Displays at the Cleveland Metroparks Zoo will focus on the use of space and aeronautics technology for sustainable energy on Earth, including the NASA-led Renewable Hydrogen Today project to construct a hydrogen fueling station at the Great Lakes Science Center.

Goddard Space Flight Center, Greenbelt, Md.
Mon., April 19 (1-2 p.m. EDT) -- Goddard's Digital Learning Network will broadcast a performance of "Bella Gaia" (Beautiful Earth), a multimedia journey across our planet that combines views of Earth from space, scientific visualization and an original score from director and composer Kenji Williams. NASA scientist Christopher Shuman also provides a first-hand look at the changing face of Antarctica. The performance will be broadcast and streamed live on NASA TV's Education channel at http://www.nasa.gov/ntv.

Langley Research Center, Hampton, Va.
Thurs., April 22 (4-5 p.m. EDT) -- NASA scientist Thomas Charlock will discuss global climate change with teachers during a live webcast on the Digital Learning Network at: http://dln.nasa.gov/dln.

Sat., April 24 (10 a.m.-3 p.m. EDT) -- Exhibits and speakers will be at the Virginia Zoo's "Party for the Planet: Earth Day at the Zoo" in Norfolk, Va.

Marshall Space Flight Center, Huntsville, Ala.
Thurs., April 22 (10 a.m.-12:30 p.m. CDT) -- Activities on the theme "reducing our carbon footprint" include a talk about energy by an expert from the Tennessee Valley Authority, a tree-planting ceremony and an environmental vendor exposition.

Stennis Space Center near Bay St. Louis, Miss.
Tues., April 27 (8:30 a.m.-2 p.m. CDT) -- An environmental workshop for elementary school teachers, "Helping Our Planet Earth: It's Up to You and Me," includes classroom activities about animal habitats, "green" tips, recycling and other topics.

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NASA Continues to Track Persistent Iceland Volcano

The continuing eruption of Iceland's Eyjafjallajökull volcano was observed Mon., April 19, 2010, by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) instrument onboard NASA's Terra spacecraft. The new image shows a white eruption column being carried toward the south by prevailing winds. The image is dominated by the gray, ash-laden eruption cloud dispersed south and east by the winds, blowing from the southern Iceland coast toward Europe. The bright red areas mark the hot lava at the current vent (upper left), and the still-hot lava flows from the earlier phases of the eruption (upper center). The high-temperature material is revealed by ASTER's thermal infrared bands.

This image covers an area of 58.6 by 46.8 kilometers (36.3 by 29 miles). The resolution is 15 meters (49 feet) per pixel.

Read more at http://photojournal.jpl.nasa.gov/catalog/PIA13049

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NASA Satellite Eyes Iceland Volcano Cauldron

On Saturday, April 17, 2010, the Hyperion instrument onboard NASA's Earth Observing-1 (EO-1) spacecraft obtained this pair of images of the continuing eruption of Iceland's Eyjafjallajökull volcano. In the left-hand image, created from visible wavelengths, new black ash deposits are visible on the ground, as well as nearby brilliant unsullied ice and snow and the volcano's brown, billowing plume. The plume's dark color reflects its large ash content. These fine particles of pulverized rock are carried high into the atmosphere, where they create a hazard for aviation and are carried long distances by the prevailing winds.

In contrast, the false-color, infrared image at the right reveals the intense thermal emissions (at least 60 megawatts, or 60 million watts) emanating from the vent at the base of the massive plume. This thermal emission, equivalent to the energy consumption of 60,000 homes, represents only a small proportion of the total energy being released by the volcano as its molten lava interacts violently with ice and water. Each image covers an area measuring 7.7 kilometers (4.8 miles) wide, and has a resolution of 30 meters (98 feet) per pixel. The vertical direction is north-northeast.

The EO-1 spacecraft is managed by NASA's Goddard Space Flight Center, Greenbelt, Md. EO-1 is the satellite remote-sensing asset used by the Volcano Sensor Web developed by NASA's Jet Propulsion Laboratory, Pasadena, Calif., which is being used to monitor this, and other, volcanic eruptions around the world.

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NASA's Cassini Sees Lightning on Saturn

NASA's Cassini spacecraft has captured images of lightning on Saturn. The images have allowed scientists to create the first movie showing lightning flashing on another planet.

After waiting years for Saturn to dim enough for the spacecraft's cameras to detect bursts of light, scientists were able to create the movie, complete with a soundtrack that features the crackle of radio waves emitted when lightning bolts struck.

"This is the first time we have the visible lightning flash together with the radio data," said Georg Fischer, a radio and plasma wave science team associate based at the Space Research Institute in Graz, Austria. "Now that the radio and visible light data line up, we know for sure we are seeing powerful lightning storms."

The movie and radio data suggest extremely powerful storms with lightning that flashes as brightly as the brightest super-bolts on Earth, according to Andrew Ingersoll, a Cassini imaging science subsystem team member at the California Institute of Technology in Pasadena. "What's interesting is that the storms are as powerful -- or even more powerful -- at Saturn as on Earth," said Ingersoll. "But they occur much less frequently, with usually only one happening on the planet at any given time, though it can last for months."

The first images of the lightning were captured in August 2009, during a storm that churned from January to October 2009 and lasted longer than any other observed lightning storm in the solar system. Results are described in an article accepted for publication in the journal Geophysical Research Letters.

To make a video, scientists needed more pictures with brighter lightning and strong radio signals. Data were collected during a shorter subsequent storm, which occurred from November through mid-December 2009. The frames in the video were obtained over 16 minutes on Nov. 30, 2009. The flashes lasted less than one second. The images show a cloud as long as 3,000 kilometers (1,900 miles) across and regions illuminated by lightning flashes about 300 kilometers (190 miles) in diameter. Scientists use the width of the flashes to gauge the depth of the lightning below the cloud tops.

When lightning strikes on Earth and on Saturn, it emits radio waves at a frequency that can cause static on an AM radio. The sounds in the video approximate that static sound, based on Saturn electrostatic discharge signals detected by Cassini's radio and plasma wave science instrument.

Cassini, launched in 1997, and NASA's Voyager mission, launched in 1977, had previously captured radio emissions from storms on Saturn. A belt around the planet where Cassini has detected radio emissions and bright, convective clouds earned the nickname "storm alley." Cassini's cameras, however, had been unable to get pictures of lightning flashing.

Since Cassini's arrival at Saturn in 2004, it has been difficult to see the lightning because the planet is very bright and reflective. Sunlight shining off Saturn's enormous rings made even the night side of Saturn brighter than a full-moon night on Earth. Equinox, the period around August 2009 when the sun shone directly over the planet's equator, finally brought the needed darkness. During equinox, the sun lit the rings edge-on only and left the bulk of the rings in shadow.

Seeing lightning was another highlight of the equinox period, which already enabled scientists to see clumps in the rings as high as the Rocky Mountains.

"The visible-light images tell us a lot about the lightning," said Ulyana Dyudina, a Cassini imaging team associate based at Caltech, who was the first to see the flashes. "Now we can begin to measure how powerful these storms are, where they form in the cloud layer and how the optical intensity relates to the total energy of the thunderstorms."

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 in Pasadena, manages the Cassini-Huygens mission for NASA's Science Mission Directorate in Washington. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL.

Get information about patio misting system and misting systems

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Cassini Finishes Saturnian Doubleheader

NASA's Cassini spacecraft completed its double flyby this week, swinging by Saturn's moons Titan and Dione with no maneuver in between. The spacecraft has beamed back stunning raw images of fractured terrain and craters big and small on Dione, a moon that had only been visited once before by Cassini.

The Titan flyby took place April 5, and the Dione flyby took place April 7 in the UTC time zone, and April 6 Pacific time. During the Titan flyby, an unexpected autonomous reset occurred and Cassini obtained fewer images of Titan than expected. But the cameras were reset before reaching Dione, which was the primary target on this double flyby.

Scientists are poring over data from Dione to discern whether the moon could be a source of charged particles to the environment around Saturn and material to one of its rings. They are also trying to understand the history of dark material found on Dione.

A fortuitous alignment of these moons allowed Cassini to attempt this doubleheader. Cassini had made three previous double flybys and another two are planned in the years ahead. The mission is nearing the end of its first extension, known as the Equinox Mission. It will begin its second mission extension, known as the Solstice Mission, in October 2010.

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 in Pasadena, manages the Cassini-Huygens mission for NASA's Science Mission Directorate in Washington. The Cassini orbiter was designed, developed and assembled at JPL.

More information about the Titan flyby, dubbed "T67," is available at: http://saturn.jpl.nasa.gov/mission/flybys/titan20100405/.

More information about the Dione flyby, dubbed "D2," is available at: http://saturn.jpl.nasa.gov/mission/flybys/dione20100407/.

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Galaxy Evolution Explorer Spies Band of Stars

The Galaxy Evolution Explorer's ultraviolet eyes have captured a globular star cluster, called NGC 362, in our own Milky Way galaxy. In this new image, the cluster appears next to stars from a more distant neighboring galaxy, known as the Small Magellanic Cloud.

"This image is so interesting because it allows a study of the final stages of evolution of low-mass stars in NGC 362, as well as the history of star formation in the Small Magellanic Cloud," said Ricardo Schiavon of the University of Virginia, Charlottesville, Va.

Globular clusters are densely packed bunches of old stars scattered in galaxies throughout the universe. NGC 362, located 30,000 light-years away, can be spotted as the dense collection of mostly yellow-tinted stars surrounding a large white-yellow spot toward the top-right of this image. The white spot is actually the core of the cluster, which is made up of stars so closely packed together that the Galaxy Evolution Explorer cannot see them individually.

The light blue dots surrounding the cluster core are called extreme horizontal branch stars. These stars used to be very similar to our sun and are nearing the end of their lives. They are very hot, with temperatures reaching up to about four times that of the surface of our sun (25,000 Kelvin or 45,500 degrees Fahrenheit).

A star like our sun spends most of its life fusing hydrogen atoms in its core into helium. When the star runs out of hydrogen in its core, its outer envelope will expand. The star then becomes a red giant, which burns hydrogen in a shell surrounding its inner core. Throughout its life as a red giant, the star loses a lot of mass, then begins to burn helium at its core. Some stars will have lost so much mass at the end of this process, up to 85 percent of their envelopes, that most of the envelope is gone. What is left is a very hot ultraviolet-bright core, or extreme horizontal branch star.

Blue dots scattered throughout the image are hot, young stars in the Small Magellanic Cloud, a satellite galaxy of the Milky Way located approximately 200,000 light-years away. The stars in this galaxy are much brighter intrinsically than extreme horizontal branch stars, but they appear just as bright because they are farther away. The blue stars in the Small Magellanic Cloud are only about a few tens of millions of years old, much younger than the approximately 10-million-year-old stars in NGC 362.

Because NGC 362 sits on the northern edge of the Small Magellanic Cloud galaxy, the blue stars are denser toward the south, or bottom, of the image.

Some of the yellow spots in this image are stars in the Milky Way galaxy that are along this line of sight. Astronomers believe that some of the other spots, particularly those closer to NGC 362, might actually be a relatively ultraviolet-dim family of stars called "blue stragglers." These stars are formed from collisions or close encounters between two closely orbiting stars in a globular cluster.

"This observation could only be done with the Galaxy Evolution Explorer because it is the only ultraviolet imager available to the astronomical community with such a large field of view," said Schiavon.

This image is a false-color composite, where light detected by the Galaxy Evolution Explorer's far-ultraviolet detector is colored blue, and light from the telescope's near-ultraviolet detector is red.

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NASA-Funded Research Suggests Venus is Geologically Alive

For the first time, scientists have detected clear signs of recent lava flows on the surface of Venus.

The observations reveal that volcanoes on Venus appeared to erupt between a few hundred years to 2.5 million years ago. This suggests the planet may still be geologically active, making Venus one of the few worlds in our solar system that has been volcanically active within the last 3 million years.

The evidence comes from the European Space Agency's Venus Express mission, which has been in orbit around the planet since April 2006. The science results were laid over topographic data from NASA's Magellan spacecraft. Magellan radar-mapped 98 percent of the surface and collected high-resolution gravity data while orbiting Venus from 1990 to 1994.

Scientists see compositional differences compared to the surrounding landscape in three volcanic regions. Relatively young lava flows have been identified by the way they emit infrared radiation. These observations suggest Venus is still capable of volcanic eruptions. The findings appear in the April 8 edition of the journal Science.

"The geological history of Venus has long been a mystery," said Sue Smrekar, a scientist at NASA's Jet Propulsion Laboratory in Pasadena, Calif., and lead author of the paper describing the work. "Previous spacecraft gave us hints of volcanic activity, but we didn't know how long ago that occurred. Now we have strong evidence right at the surface for recent eruptions."

The volcanic provinces, or hotspots, on which Smrekar and her team focused are geologically similar to Hawaii. Scientists previously detected plumes of hot rising material deep under Venus' surface. Those plumes are thought to have produced significant volcanic eruptions. Other data from the planet suggest that volatile gases commonly spewed from volcanoes were breaking down in its atmosphere. The rate of volcanism will help scientists determine how the interior of the planet works and how gases emitted during eruptions affect climate.

Something is smoothing Venus' surface, because the planet has only about 1,000 craters, a relatively small amount compared to other bodies in our solar system. Scientists think it may be the result of volcanic activity and want to know if it happens quickly or slowly. The Venus Express results suggest a gradual sequence of smaller volcanic eruptions as opposed to a cataclysmic volcanic episode that resurfaces the entire planet with lava.

Smrekar and her team also discovered that several volcanic features in the regions they studied show evidence of minerals found in recent lava flows. These mineral processes correspond to the youngest volcanic flows in each region, giving scientists additional support for the idea they formed during recent volcanic activity. On Earth, lava flows react rapidly with oxygen and other elements in the atmosphere when they erupt to the surface. On Venus, the process is similar, although it is more intense and changes the outer layer more substantially.

Scientists call Venus Earth's sister planet because of similarities in size, mass, density and volume. Scientists deduce that both planets shared a common origin, forming at the same time about 4.5 billion years ago. Venus also is the planet on which the runaway greenhouse effect was discovered. The planet is cloaked in a much less friendly atmosphere than that found on Earth. It is composed chiefly of carbon dioxide, which generates a surface temperature hot enough to melt lead, and a surface pressure 90 times greater than that on Earth.

The small group of worlds in our solar system known to be volcanically active today includes Earth and Jupiter's moon Io. Crater counts on Mars also have suggested recent lava flows. Scientists are studying evidence of another kind of active volcanism that involves ice-spewing volcanoes on other moons in our solar system.

NASA sponsored Smrekar's research. The European Space Agency built and manages Venus Express. JPL is managed for NASA by the California Institute of Technology in Pasadena.

To view the spacecraft data and images, visit: http://www.nasa.gov/topics/solarsystem/features/pia13001.html

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NASA's Global Hawk Completes First Science Flight

NASA has successfully completed the first science flight of the Global Hawk unpiloted aircraft system over the Pacific Ocean. The flight was the first of five scheduled for this month's Global Hawk Pacific, or GloPac, mission to study atmospheric science over the Pacific and Arctic oceans.

The Global Hawk is a robotic plane that can fly autonomously to altitudes above 18,288 meters (60,000 feet) -- roughly twice as high as a commercial airliner -- and as far as 20,372 kilometers (11,000 nautical miles), which is half the circumference of Earth. Operators pre-program a flight path, then the plane flies itself for as long as 30 hours, staying in contact through satellite and line-of-site communications links to a ground control station at NASA's Dryden Flight Research Center in California's Mojave Desert.

"The Global Hawk is a revolutionary aircraft for science because of its enormous range and endurance," said Paul Newman, co-mission scientist for GloPac and an atmospheric scientist from NASA's Goddard Space Flight Center in Greenbelt, Md. "No other science platform provides the range and time to sample rapidly evolving atmospheric phenomena. This mission is our first opportunity to demonstrate the unique capabilities of this plane, while gathering atmospheric data in a region that is poorly sampled."

GloPac researchers plan to directly measure and sample greenhouse gases, ozone-depleting substances, aerosols and constituents of air quality in the upper troposphere and lower stratosphere. GloPac's measurements will cover longer time periods and greater geographic distances than any other science aircraft.

During Wednesday's flight, the plane flew approximately 8,334 kilometers (4,500 nautical miles) along a flight path that took it to 150.3 degrees West longitude, and 54.6 degrees North latitude, just south of Alaska's Kodiak Island. The flight lasted just over 14 hours and flew up to 18,562 meters (60,900 feet). The mission is a joint project with the National Oceanic and Atmospheric Administration, or NOAA.

The plane carries 11 instruments to sample the chemical composition of the troposphere and stratosphere, including two from NASA's Jet Propulsion Laboratory, Pasadena, Calif.. The instruments profile the dynamics and meteorology of both layers and observe the distribution of clouds and aerosol particles. Project scientists expect to take observations from the equator north to the Arctic Circle and west of Hawaii.

Although the plane is designed to fly on its own, pilots can change its course or altitude based on interesting atmospheric phenomena ahead. Researchers have the ability via communications links to control their instruments from the ground.

"The Global Hawk is a fantastic platform because it gives us expanded access to the atmosphere beyond what we have with piloted aircraft," said David Fahey, co-mission scientist and a research physicist at NOAA's Earth System Research Laboratory in Boulder, Colo. "We can go to regions we couldn't reach or go to previously explored regions and study them for extended periods that are impossible with conventional planes."

The timing of GloPac flights should allow scientists to observe the breakup of the polar vortex. The vortex is a large-scale cyclone in the upper troposphere and lower stratosphere that dominates winter weather patterns around the Arctic and is particularly important for understanding ozone depletion in the Northern Hemisphere.

Scientists also expect to gather high-altitude data between 13,716 and 19,812 meters (45,000 and 65,000 feet), where many greenhouse gases and ozone-depleting substances are destroyed. They will measure dust, smoke and pollution that cross the Pacific from Asia and Siberia and affect U.S. air quality.

Global Hawk will make several flights under NASA's Aura satellite and other "A-train" Earth-observing satellites, "allowing us to calibrate and confirm what we see from space," Newman added. GloPac is specifically being conducted in conjunction with NASA's Aura Validation Experiment.

GloPac includes more than 130 researchers and technicians from Goddard, Dryden Flight Research Center, JPL, and Ames Research Center in Moffett Field, Calif. Also involved are NOAA's Earth System Research Laboratory; the University of California, Santa Cruz; Droplet Measurement Technologies of Boulder, Colo.; and the University of Denver.

NASA Dryden and the Northrop Grumman Corp. of Rancho Bernardo, Calif., signed a Space Act Agreement to re-fit and maintain three Global Hawks transferred from the U.S. Air Force for use in high-altitude, long-duration Earth science missions.

For more on GloPac, visit: http://www.nasa.gov/topics/earth/features/global-hawk.html . JPL is managed for NASA by the California Institute of Technology in Pasadena.

For more information on the GloPac instruments, see: http://www.nasa.gov/centers/dryden/research/GloPac/glopac_instruments.html

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Juno Taking Shape in Denver

Assembly has begun on NASA's Juno spacecraft, which will help scientists understand the origin and evolution of Jupiter. The mission, whose principal investigator is Scott Bolton of Southwest Research Institute in San Antonio, Tex., is expected to launch in August 2011 and reach Jupiter in 2016.

The assembly, testing and launch operations phase began April 1 in a high-bay clean room at Lockheed Martin Space Systems in Denver. Engineers and technicians will spend the next few months fitting instruments and navigation equipment onto the spacecraft.

"We're excited the puzzle pieces are coming together," Bolton said. "We're one important step closer to getting to Jupiter."

Jupiter is the largest planet in our solar system. Underneath its dense cloud cover, the planet safeguards secrets to the fundamental processes and conditions that governed our solar system during its formation. As our primary example of a giant planet, Jupiter can also provide critical knowledge for understanding the planetary systems being discovered around other stars.

Juno will have nine science instruments on board to investigate the existence of a solid planetary core, map Jupiter's intense magnetic field, measure the amount of water and ammonia in the deep atmosphere, and observe the planet's auroras.

"We plan to be doing a lot of testing in the next few months," said Jan Chodas, the project manager based at NASA's Jet Propulsion Laboratory in Pasadena, Calif. "We want to make sure the spacecraft is ready for the long journey to Jupiter and the harsh environment it will encounter there."

JPL manages the Juno mission for the principal investigator, Scott Bolton. Lockheed Martin Space Systems is building the spacecraft. The Italian Space Agency, Rome, is contributing an infrared spectrometer instrument and a portion of the radio science experiment.

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Cassini Doubleheader: Flying By Titan and Dione

In a special double flyby early next week, NASA's Cassini spacecraft will visit Saturn's moons Titan and Dione within a period of about a day and a half, with no maneuvers in between. A fortuitous cosmic alignment allows Cassini to attempt this doubleheader, and the interest in swinging by Dione influenced the design of its extended mission.

The Titan flyby, planned for Monday, April 5, will take Cassini to within about 7,500 kilometers (4,700 miles) of the moon's surface. The distance is relatively long as far as encounters go, but it works to the advantage of Cassini's imaging science subsystem. Cassini's cameras will be able to stare at Titan's haze-shrouded surface for a longer time and capture high-resolution pictures of the Belet and Senkyo areas, dark regions around the equator that ripple with sand dunes.

In the early morning of Wednesday, April 7 in UTC time zones, which is around 9 p.m. on Tuesday, April 6 in California, Cassini will make its closest approach to the medium-sized icy moon Dione. Cassini will plunge to within about 500 kilometers (300 miles) of Dione's surface.

This is only Cassini's second close encounter with Dione. The first flyby in October 2005, and findings from the Voyager spacecraft in the 1990s, hinted that the moon could be sending out a wisp of charged particles into the magnetic field around Saturn and potentially exhaling a diffuse plume that contributes material to one of the planet's rings. Like Enceladus, Saturn's more famous moon with a plume, Dione features bright, fresh fractures. But if there were a plume on Dione, it would certainly be subtler and produce less material.

Cassini plans to use its magnetometer and fields and particles instruments to see if it can find evidence of activity at Dione. Thermal mapping by the composite infrared spectrometer will also help in that search. In addition, the visual and infrared mapping spectrometer will examine dark material found on Dione. Scientists would like to understand the source of this dark material.

Cassini has made three previous double flybys and another two are planned in the years ahead. The mission is nearing the end of its first extension, known as the Equinox mission. It will begin its second mission extension, known as the Solstice Mission, in October 2010.

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 in Pasadena, manages the Cassini-Huygens mission for NASA's Science Mission Directorate in Washington. The Cassini orbiter was designed, developed and assembled at JPL.

More information about the Titan flyby, dubbed "T67," is available at:
http://saturn.jpl.nasa.gov/mission/flybys/titan20100405/ .

More information about the Dione flyby, dubbed "D2," is available at:
http://saturn.jpl.nasa.gov/mission/flybys/dione20100407/

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Spirit May Have Begun Months-Long Hibernation

NASA's Mars Exploration Rover Spirit skipped a planned communication session on March 30 and, as anticipated from recent power-supply projections, has probably entered a low-power hibernation mode.

In this mode, the rover's clock keeps running, but communications and other activities are suspended in order to put all available energy into heating and battery recharging. When the battery charge is adequate, the rover attempts to wake up and communicate on a schedule it knows.

"We may not hear from Spirit again for weeks or months, but we will be listening at every opportunity, and our expectation is that Spirit will resume communications when the batteries are sufficiently charged," said John Callas of NASA's Jet Propulsion Laboratory, Pasadena, Calif., who is project manager for Spirit and its twin rover, Opportunity.

Spirit's power supply is low because daily sunshine for dusty solar panels is declining with the approach of the winter solstice, in mid-May, in Mars' southern hemisphere. In the three previous Martian winters that Spirit has survived since landing in January 2004, the rover was tilted northward to put its solar panels at a favorable angle toward the sun. That preparation was not possible this winter because of impaired mobility. Spirit's wheels are dug into soft sand, and the rover lost the use of a second wheel four months ago. It had previously lost use of one of its six wheels four years ago.

Spirit's original mission was planned to last for three months. The rover has worked extended missions since April 2004. Opportunity is currently on a long-term trek toward a large crater named Endeavour.

Spirit had been communicating on a once-per-week schedule in recent weeks. During the designated time for the rover to communicate with NASA's Mars Odyssey orbiter passing overhead on March 30, Odyssey heard nothing from the rover.

"We are checking other less-likely possibilities for the missed communication, but this probably means that Spirit tripped a low-power fault sometime between the last downlink on March 22 and yesterday," Callas said. "The recent downlinks had indicated that the battery state of charge was decreasing, getting close to the level that would put Spirit into this hibernation."

In coming weeks, Spirit's core electronics will become colder than any temperature they have ever experienced on Mars. Thermal projections indicate the temperature probably will not drop lower than the electronics were designed and tested to tolerate, but the age of the rover adds to the uncertainty of survival.

"The temperature limit was for a new rover. We now have an older rover with thousands of thermal cycles on Mars, so the colder temperatures will be a further stress," Callas said. JPL, a division of the California Institute of Technology in Pasadena, manages the Mars Exploration Rover Project for NASA's Science Mission Directorate, Washington. For more information about the Mars rovers, visit http://www.nasa.gov/rovers .

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