NASA Spacecraft Hours From Comet Encounter

As of today, Feb. 14, at 9:21 a.m. PST (12:21 p.m. EST), NASA's Stardust-NExT mission spacecraft is within a quarter-million miles (402,336 kilometers) of its quarry, comet Tempel 1, which it will fly by tonight. The spacecraft is cutting the distance with the comet at a rate of about 10.9 kilometers per second (6.77 miles per second or 24,000 mph).

The flyby of Tempel 1 will give scientists an opportunity to look for changes on the comet's surface since it was visited by NASA's Deep Impact spacecraft in July 2005. Since then, Tempel 1 has completed one orbit of the sun, and scientists are looking forward to discovering any differences in the comet.

The closest approach is expected tonight at approximately 8:40 p.m. PST (11:40 p.m. EST).

During the encounter phase, the spacecraft will carry out many important milestones in short order and automatically, as the spacecraft is too far away to receive timely updates from Earth. These milestones include turning the spacecraft to point its protective shields between it and the anticipated direction from which cometary particles would approach. Another milestone will occur at about four minutes to closest approach, when the spacecraft will begin science imaging of the comet's nucleus.

NASA Hosting Events for Valentine's Night Comet Encounter

NASA will host several live activities for the Stardust-NExT mission's close encounter with comet Tempel 1. The closest approach is expected at approximately 8:37 p.m. PST (11:37 p.m. EST) on Feb. 14, with confirmation received on Earth at about 8:56 p.m. PST (11:56 p.m. EST).

Live coverage of the Tempel 1 encounter will begin at 8:30 p.m. PST on Feb. 14 on NASA Television and the agency's website. The coverage will include live commentary from mission control at NASA's Jet Propulsion Laboratory in Pasadena, Calif., and video from Lockheed Martin Space System's mission support area in Denver.

NASA's Kepler Spacecraft Discovers Extraordinary New Planetary System

Scientists using NASA's Kepler, a space telescope, recently discovered six planets made of a mix of rock and gases orbiting a single sun-like star, known as Kepler-11, which is located approximately 2,000 light years from Earth.

"The Kepler-11 planetary system is amazing," said Jack Lissauer, a planetary scientist and a Kepler science team member at NASA's Ames Research Center, Moffett Field, Calif. "It’s amazingly compact, it’s amazingly flat, there’s an amazingly large number of big planets orbiting close to their star - we didn’t know such systems could even exist."

In other words, Kepler-11 has the fullest, most compact planetary system yet discovered beyond our own.

"Few stars are known to have more than one transiting planet, and Kepler-11 is the first known star to have more than three," said Lissauer. "So we know that systems like this are not common. There’s certainly far fewer than one percent of stars that have systems like Kepler-11. But whether it’s one in a thousand, one in ten thousand or one in a million, that we don’t know, because we only have observed one of them."

NASA Spacecraft Prepares for Valentine's Day Comet Rendezvous

NASA's Stardust-NExT spacecraft is nearing a celestial date with comet Tempel 1 at approximately 8:37 p.m. PST (11:37 p.m. EST), on Feb. 14. The mission will allow scientists for the first time to look for changes on a comet's surface that occurred following an orbit around the sun.

The Stardust-NExT, or New Exploration of Tempel, spacecraft will take high-resolution images during the encounter, and attempt to measure the composition, distribution, and flux of dust emitted into the coma, or material surrounding the comet's nucleus. Data from the mission will provide important new information on how Jupiter-family comets evolved and formed.

The mission will expand the investigation of the comet initiated by NASA's Deep Impact mission. In July 2005, the Deep Impact spacecraft delivered an impactor to the surface of Tempel 1 to study its composition. The Stardust spacecraft may capture an image of the crater created by the impactor. This would be an added bonus to the huge amount of data that mission scientists expect to obtain.

NASA Video Shows Global Reach of Pollution from Fires

A series of large wildfires burning across western and central Russia, eastern Siberia and western Canada has created a noxious soup of air pollution that is affecting life far beyond national borders. Among the pollutants created by wildfires is carbon monoxide, a gas that can pose a variety of health risks at ground level. Carbon monoxide is also an ingredient in the production of ground-level ozone, which causes numerous respiratory problems. As the carbon monoxide from these wildfires is lofted into the atmosphere, it becomes caught in the lower bounds of the mid-latitude jet stream, which swiftly transports it around the globe.

Two movies were created using continuously updated data from the "Eyes on the Earth 3-D" feature on NASA's global climate change website http://climate.nasa.gov/ . They show three-day running averages of daily measurements of carbon monoxide present at an altitude of 5.5 kilometers (18,000) feet, along with its global transport. The data are from the Atmospheric Infrared Sounder (AIRS) instrument on NASA's Aqua spacecraft. AIRS is most sensitive to carbon monoxide at this altitude, which is a region conducive to long-range transport of the smoke. The abundance of carbon monoxide is shown in parts per billion, with the highest concentrations shown in yellows and reds.

The first movie, centered over Moscow, highlights the series of wildfires that continue to burn across Russia. It covers the period between July 18 and Aug. 10, 2010.

The second movie is centered over the North Pole and covers the period from July 16 to Aug. 10, 2010. From this vantage point, the long-range transport of pollutants is more easily visible.

AIRS is managed by NASA's Jet Propulsion Laboratory, Pasadena, Calif., under contract to NASA. JPL is a division of the California Institute of Technology in Pasadena.

More information about AIRS can be found at http://airs.jpl.nasa.gov .

For more information visit http://www.nasa.gov/topics/earth/features/earth20100811.html

Ping-Pong Balls to Float Crew Capsule Simulator

If ping-pong balls can float a sunken boat, they should be able to keep an uncrewed space capsule simulator from sinking.

Right?

That's what a team of summer students and engineers think at NASA's Langley Research Center in Hampton, Va. Langley is fabricating a proposed design of an astronaut crew module simulator for uncrewed flight-testing as part of the agency's effort to build a vehicle to replace the space shuttle.

The Orion crew exploration vehicle is the nation's next generation spacecraft designed to carry up to four astronauts to low Earth orbit and beyond.

Orion's first suborbital flight test will launch to 400,000 feet, or 75 miles above Earth. Because the crew module will not be pressurized during the test, it will not have the buoyancy of a pressurized spacecraft. This puts the simulated crew module at risk of sinking to the bottom of the Atlantic Ocean after splashdown.

To save the valuable test article for analysis and possible reuse, Langley called on a team of creative minds for a solution.

NASA Langley students gather around the crew module mockup that they propose to keep afloat with ping-pong balls after it splashes down. From left, front row: Edward Tillistrand, Brice Collamer, Patrick Cragg, Caroline Kirk and Kurian Thomas. In the capsule, from left; Joseph Randall Hunt, Heather Blount and Victor Stewart. Credit: NASA/Sean Smith

And as it turned out, inexpensive, lightweight ping-pong balls provided the answer. Langley engineer John DiNonno proposed the idea, and the Orion Flight Test Office told the team to study it.

The idea quickly became "very plausible," said student Caroline Kirk.

Way to go

"At first we didn't really realize that we were going to get so far in proving that it would be possible," said Kirk, a Suffolk, Va., native attending Virginia Tech as an aerospace engineering major. "But when we thought about everything logically, it just seemed like ping-pong balls were the way to go."

She and a team of seven other students worked the project in Langley's Mechanical Systems Branch, where they were assigned for the summer.

DiNonno got the idea from a Discovery Channel program about raising a sunken boat using 27,000 ping-pong balls.

Engineer David Covington said that when DiNonno suggested the ping-pong ball idea, "I just laughed. Not a 'what are you thinking' kind of laugh, but more of a 'that's the most awesome thing I've heard in a long time' laugh. I asked him 'are you serious?' and he said 'yeah, we're authorized to do a four-week study.' So we went straight to work."

Ensuring the outcome would be relatively low-cost was a top priority, said DiNonno.

"Recovering the capsule was not a requirement, but it was a desire," he said. "So there wasn't going to be a lot of investment in it."

Testing process

The students divided the tasks needed to determine if the idea was feasible, each becoming a "principal investigator" for a specific area.

They tested ping-pong balls of varying quality, much the way spacecraft hardware is tested. They studied how the balls would react to the near-vacuum at the edge of space. Using buoyancy tests, they determined how well the balls would float.

The students also subjected the ping-pong balls to mechanical loads using a hydraulic press, and heated them to see how they would react to the high temperatures of descent into the Earth's atmosphere. And they performed electrostatic discharge tests to determine if the balls would produce a static charge that could disrupt the space capsule's electronics.

Ping-Pong Ball Facts

›› Ping-pong balls are made of celluloid, which is processed cotton.
›› Each ping-pong ball weighs less than an ounce (2.7 grams) and is roughly 1.5 inches (38 - 40 mm) in diameter.
›› Ping-pong ball quality is rated from zero to three stars.

Credit: Microsoft

The ping-pong balls passed all the challenges, said Heather Blount, a materials science engineering student at Virginia Tech.

"Through all our testing and calculations, we figured out that it could be a safe and viable option," said Blount, of Yorktown, Va.

Keeping the crew module afloat would take at least 150,000 ping-pong balls, the students estimate, at a retail price of 50 cents or less each -- a fraction of the cost of traditional options. The students hope to reduce the cost through a bulk purchase.

If the flight test is approved, the ping-pong ball concept would still need to be vetted with the flight test team and reviewed by NASA senior management. If implemented, the ping-pong balls probably will be put into netted bags and secured inside the crew module just prior to launch. They would virtually fill the available space inside the uncrewed capsule.

Then, when the unsealed capsule splashes down, the buoyancy of the ping-pong balls will offset the weight of incoming water and it will float instead of sink.

The ping-pong balls also will reduce the volume of air that needs to be vented from the capsule during ascent - as well as drawn in during descent - as the capsule travels through significant changes in atmospheric pressure.

'Awesome' students

Approval of the flight test, as well as a launch date, has yet to be determined. "Even if it is not used, it's an idea that's out there that someone else could use," said Langley engineer Amanda Cutright, a student mentor.

Cutright said she has been enthused by the students.

"It's awesome working with them," she said. "They bring a different perspective. I've been really impressed with how quickly they pick up new ideas and new technology. It seems each team of students that we mentor learns quicker and is able to provide creative ideas."

Yammer

The ping-pong ball team has been using a social media tool called Yammer to communicate with each other, share files, links, work status, questions, and solutions.

"Yammer has been a great tool to communicate with the interns," said Brendan Shaughnessy, an engineer in the Mechanical Systems Branch. "They can post updates on their work or links to websites they found. I can also let them all know about something I need them to do or that I've done in one quick message."

To join NASA's Yammer site, you must have an email address that ends in nasa.gov.

The Orion FTA Students site is open to anyone with a NASA Yammer account.

Credit: Yammer.com

Kirk said the ping-pong ball project has been a unique experience. At school, she said, "we do lab experiments but nothing similar to this at all. Being able to develop an experiment that will be used for space flight tests is an opportunity of a lifetime."

NASA employees and contractors involved in the project include engineers Amanda Cutright; Brendan Shaughnessy, Analytical Services and Materials Inc.; David Covington, ATK Space Systems Inc.; and John DiNonno, all of the Mechanical Systems Branch.

Student team members:

Brice Collamer, Virginia Tech, Langley Aerospace Research Summer Scholars (LARSS) program
→ Principal investigator for electrostatic discharge tests
Patrick Cragg, Princeton University, DEVELOP program
→ Principal investigator for further testing and research
Kurian Thomas, University of Virginia, DEVELOP program
→ Principal investigator for loading tests and cost analysis
Caroline Kirk, Virginia Tech, LARSS
→ Co-principal investigator for vacuum oven tests
Joseph Randall Hunt, Western Carolina University, Undergraduate Student Research Program
→ Principal investigator for packing efficiency tests and operations concerns
Heather Blount, Virginia Tech, LARSS
→ Co-principal investigator for vacuum oven tests
Edward Tillistrand, University of Virginia, DEVELOP program
→ Principal investigator for buoyancy tests and quantity analysis
Victor Stewart, Virginia Tech, Cooperative Education Program
→ Principal investigator for support and review of experiment work

For more information visit http://www.nasa.gov/mission_pages/constellation/orion/orionfta-pingpong.html

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IBEX Spacecraft Finds Discoveries Close to Home

Imagine floating 35,000 miles above the sunny side of Earth. Our home planet gleams below, a majestic whorl of color and texture. All seems calm around you. With no satellites or space debris to dodge, you can just relax and enjoy the black emptiness of space.

But looks can be deceiving.

In reality, you've unknowingly jumped into an invisible mosh pit of electromagnetic mayhem — the place in space where a supersonic "wind" of charged particles from the Sun crashes head-on into the protective magnetic bubble that surrounds our planet. Traveling at a million miles per hour, the solar wind's protons and electrons sense Earth's magnetosphere too late to flow smoothly around it. Instead, they're shocked, heated, and slowed almost to a stop as they pile up along its outer boundary, the magnetopause, before getting diverted sideways.

Space physicists have had a general sense of these dynamic goings-on for decades. But it wasn't until the advent of the Interstellar Boundary Explorer or IBEX, a NASA spacecraft launched in October 2008, that they've been able to see what the human eye cannot: the first-ever images of this electromagnetic crash scene. They can now witness how some of the solar wind's charged particles are being neutralized by gas escaping from Earth's atmosphere.

A New Way to See Atoms

IBEX wasn't designed to keep tabs on Earth's magnetosphere. Instead, its job is to map interactions occurring far beyond the planets, 8 to 10 billion miles away, where the Sun's own magnetic bubble, the heliosphere, meets interstellar space.

IBEX found that Energetic Neutral Atoms, or ENAs, are coming from a region just outside Earth's magnetopause where nearly stationary protons from the solar wind interact with the tenuous cloud of hydrogen atoms in Earth's exosphere. Credit: NASA/Goddard Space Flight Center

Only two spacecraft, Voyagers 1 and 2, have ventured far enough to probe this region directly. IBEX, which travels in a looping, 8-day-long orbit around Earth, stays much closer to home, but it carries a pair of detectors that can observe the interaction region from afar.

Here's how: When fast-moving protons in the solar wind reach the edge of the heliosphere, they sometimes grab electrons from the slower-moving interstellar atoms around them, like batons getting passed between relay runners. This charge exchange creates electrically neutral hydrogen atoms that are no longer controlled by magnetic fields. Suddenly, they're free to go wherever they want — and because they're still moving fast, they quickly zip away from the interstellar boundary in all directions.

> Download video

This animation shows a neutral solar particle's path leaving the Sun, following the magnetic field lines out to the Heliosheath. The solar particle hits a hydrogen atom, stealing it's electron and we follow it until we see it hit one of IBEXs detectors. Credit: NASA/Goddard Space Flight Center

Some of these "energetic neutral atoms," or ENAs, zip past Earth, where they're recorded by IBEX. Its two detectors don't take pictures with conventional optics. Instead, they record the number and energy of atoms arriving from small spots of sky about 7 degrees across (the apparent size of a tennis ball held at arm's length). Because its spin axis always points at the Sun, the spacecraft slowly turns throughout Earth's orbit and its detectors scan overlapping strips that create a complete 360 degrees map every six months.

A Collision Zone Near Earth

Because IBEX is orbiting Earth, it also has a front-row seat for observing the chaotic pileup of solar-wind particles occurring along the "nose" of Earth's magnetopause, about 35,000 miles out. ENAs are created there too, as solar-wind protons wrest electrons from hydrogen atoms in the outermost vestiges of our atmosphere, the exosphere.

Other spacecraft have attempted to measure the density of the dayside exosphere, without much success. NASA's Imager for Magnetopause-to-Aurora Global Exploration (IMAGE) spacecraft probably detected ENAs from this region a decade ago, but its detectors didn't have the sensitivity to pinpoint or measure the source.

Now, thanks to IBEX, we know just how tenuous the outer exosphere really is. "Where the interaction is strongest, there are only about eight hydrogen atoms per cubic centimeter," explains Stephen A. Fuselier, the Lockheed Martin Space Systems researcher who led the mapping effort. His team's results appear in the July 8 issue of Geophysical Research Letters.

The key observations were made in March and April 2009, when IBEX was located far from Earth — about halfway to the Moon's orbit — and its detectors could scan the region directly in front of the magnetopause. During some of the March observations, the European Space Agency's Cluster 3 spacecraft was positioned just in front of the magnetopause, where it measured the number of deflected solar-wind protons directly. "Cluster played a very important role in this study," Fuselier explains. "It was in the right place at the right time."

Artist concept of the IBEX satellite. Credit: NASA/Goddard Space Flight Center

The new IBEX maps show that the ENAs thin out at locations away from the point of peak intensity. This falloff makes sense, Fuselier says, because Earth's magnetopause isn't spherical. Instead, it has a teardrop shape that's closest to Earth at its nose but farther away everywhere else. So at locations well away from the magnetopause's centerline, even fewer of the exosphere's hydrogen atoms are hanging around to interact with the solar wind. "No exosphere, no ENAs," he explains.

A Versatile Spacecraft

Since its launch, IBEX has also scanned another nearby world, with surprising results. The moon has no atmosphere or magnetosphere, so the solar wind slams unimpeded into its desolate surface. Most of those particles get absorbed by lunar dust. In fact, space visionaries wonder if the moon's rubbly surface has captured enough helium-3, an isotope present in tiny amounts in the Sun's outflow, to serve as a fuel for future explorers.

Yet cosmic chemists have long thought that some solar-wind protons must be bouncing off the lunar surface, becoming ENAs through charge exchange as they do. So does the moon glow in IBEX's scans? Indeed it does, says David J. McComas of Southwest Research Institute in San Antonio, Texas, who serves as the mission's Principal Investigator.

In a report published last year in Geophysical Research Letters, McComas and other researchers conclude that about 10 percent of the solar-wind particles striking the Moon escape to space as ENAs detectable by IBEX. That amounts to roughly 150 tons of recycled hydrogen atoms per year.

Meanwhile, the squat, eight-sided spacecraft continues its primary task of mapping the interactions between the outermost heliosphere and the interstellar medium that lies beyond. McComas and his team are especially eager to learn more about the mysterious and unexpected "ribbon" of ENAs that turned up in the spacecraft's initial all-sky map.

At NASA's Goddard Space Flight Center in Greenbelt, Md., IBEX Mission Scientist Robert MacDowall says the spacecraft should be able to continue its observations through at least 2012. "We weren't sure those heliospheric interactions would vary with time, but they do," he explains, "and it's great that IBEX will be able to record them for years to come."

For more information visit http://www.nasa.gov/mission_pages/ibex/em-crash.html

Cassini Bags Enceladus 'Tigers'

NASA's Cassini spacecraft has successfully completed its flyby over the "tiger stripes" in the south polar region of Saturn's moon Enceladus and has sent back images of its passage. The spacecraft also targeted the moon Tethys.

The tiger stripes are actually giant fissures that spew jets of water vapor and organic particles hundreds of kilometers, or miles, out into space. While the winter is darkening the moon's southern hemisphere, Cassini has its own version of "night vision goggles" -- the composite infrared spectrometer instrument - to track heat even when visible light is low. It will take time for scientists to assemble the data into temperature maps of the fissures.

The camera was pointing toward Enceladus at approximately 348,913 kilometers (216,805 miles) away, and the image was taken using the CL1 and GRN filters. This image has not been validated or calibrated. A validated/calibrated image will be archived with the NASA Planetary Data System in 2011. Image Credit: NASA/JPL/Space Science Institute

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 raw images from the Enceladus flyby, dubbed "E11," are available at: http://saturn.jpl.nasa.gov/photos/raw/

More information about the Cassini-Huygens mission is at: http://www.nasa.gov/cassini and http://saturn.jpl.nasa.gov.

For more information visit http://www.nasa.gov/mission_pages/cassini/whycassini/cassini20100814.html

NASA Instrument Tracks Pollution from Russian Fires

Drought and the worst heat wave Russia has seen in 130 years have sparked a devastating outbreak of wildfires across the nation this summer, primarily in the country's western and central regions. According to wire service reports and Russia's Emergency Situations Ministry, as of Aug. 6, 2010, some 558 fires were burning. The fires have killed at least 52 people, destroyed some 2,000 homes and charred more than 1,796 square kilometers (693 square miles). Russia's capital city of Moscow is currently blanketed in a thick smog, which has curtailed activities and disrupted air traffic. According to the Associated Press, levels of carbon monoxide pollution in Moscow are at an all-time high, four times higher than normal.

The Atmospheric Infrared Sounder (AIRS) instrument on NASA's Aqua spacecraft is tracking the concentration and transport of carbon monoxide from the Russian fires. The figures presented here show the abundance of carbon monoxide present in the atmosphere at an altitude of 5.5 kilometers (18,000 feet). AIRS is sensitive to carbon monoxide in the mid-troposphere at heights between 2 and 10 kilometers (1.2 and 6.2 miles), with a peak sensitivity at an altitude of approximately 5 kilometers (3.1 miles). This region of Earth's atmosphere is also conducive to the long-range transport of the pollution that is lofted to this altitude.

Top (fig.1) and bottom (fig.2) comparison of carbon monoxide pollution from the series of devastating wildfires burning across central and western Russia, as seen by the Atmospheric Infrared Sounder (AIRS) instrument on NASA's Aqua spacecraft on July 21, 2010 (top) and Aug. 1, 2010 (bottom). The AIRS data show the abundance of carbon monoxide present in the atmosphere at an altitude of 5.5 kilometers (18,000 feet). Image credit: NASA/JPL/Leonid Yurganov, University of Maryland, Baltimore County

As shown in Figure 1, acquired July 21, 2010, the concentration of carbon monoxide from the fires on that date was largely limited to the European part of Russia (western and central Russia). This contrasts dramatically with the data in Figure 2, acquired on August 1, when the carbon monoxide concentration was much higher and the area of the fires had increased significantly. The concentration of carbon monoxide is continuing to grow. According to Aug. 4 NASA estimates, the smoke plume from the fires spans about 3,000 kilometers (1,860 miles) from east to west, approximately the distance from San Francisco to Chicago.

Fig. 3 - Changes in the total amount of carbon monoxide above western Russia, in megatons, through Aug. 1, 2010, as measured by the JPL AIRS instrument on NASA's Aqua spacecraft, are compared with 2002 data from the MOPITT instrument on NASA's Terra spacecraft and data from the year 2009, which saw normal levels of seasonal carbon monoxide. Image credit: NASA/JPL/Leonid Yurganov, University of Maryland, Baltimore County

Figure 3 shows changes in the total amount of carbon monoxide above western Russia in megatons through August 1, 2010 (shown by the red curve). The changes are plotted again the base year of 2009, which saw normal levels of seasonal carbon monoxide. This is contrasted against the year 2002, when peat fires predominated in Russia. The 2002 data are from the Measurements of Pollution in the Troposphere (MOPITT) instrument on NASA's Terra spacecraft. On August 1, 2010, the excess carbon monoxide content almost reached the maximum values seen in 2002. The rate of growth (approximately 0.7 megatons, or 700,000 metric tons, per day) characterizes the rate of emission; the current rate is approximately three times higher than in 2002.

AIRS is managed by NASA's Jet Propulsion Laboratory, Pasadena, Calif., under contract to NASA. JPL is a division of the California Institute of Technology in Pasadena. More information about AIRS can be found at http://airs.jpl.nasa.gov.

For more information visit http://www.nasa.gov/topics/earth/features/fires20100806.html

Exposed Ice in a Fresh Crater

At the center of this view of an area of mid-latitude northern Mars, a fresh crater about 6 meters (20 feet) in diameter holds an exposure of bright material, blue in this false-color image. The High-Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter made this observation on June 20, 2010.

Previous HiRISE images of fresh craters in the middle to high northern latitudes show exposed water ice on the poleward-facing slopes (see: http://www.nasa.gov/mission_pages/MRO/news/mro-20090924r.html). Here is another example. This crater formed sometime between April 2004 and January 2010, as determined from before-and-after images acquired by the Thermal Emission Imaging System camera on NASA's Mars Odyssey orbiter and the Context Camera on the Mars Reconnaissance Orbiter. This HiRISE image was acquired in northern Mars' early summer, when frost at this latitude is not expected. Scientists propose that the bright material at the crater is subsurface ice exposed by the impact that excavated the crater.

This image spans a distance of about 170 meters (about 560 feet) and is presented in false color, which aids in distinguishing among surface materials and textures. It is a portion of the HiRISE observation catalogued as ESP_018273_2245, of an area at 44 degrees north latitude, 180 degrees east longitude. Other image products from this observation are available at http://hirise.lpl.arizona.edu/ESP_018273_2245.

NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, Calif., manages the Mars Reconnaissance Orbiter for NASA's Science Mission Directorate, Washington. Lockheed Martin Space Systems, Denver, built the spacecraft. The High Resolution Imaging Science Experiment is operated by the University of Arizona, Tucson, and the instrument was built by Ball Aerospace & Technologies Corp., Boulder, Colo.

Image Credit: NASA/JPL-Caltech/University of Arizona

For more information visit http://www.nasa.gov/mission_pages/MRO/multimedia/gallery/pia13315.html

Artist's Concept of Planned 2016 Mars Mission

NASA and the European Space Agency are jointly developing the ExoMar Trace Gas Orbiter mission for launch in 2016. This is an artist's concept of the planned spacecraft, which will carry five science instruments plus a European entry, descent and landing demonstrator vehicle. The orbiter will also serve as a communications relay for Mars surface missions.

Image Credit: ESA

For more information visit http://www.nasa.gov/mission_pages/mars/images/pia13310.html

Blowing in the Wind: Cassini Helps with Dune Whodunit

The answer to the mystery of dune patterns on Saturn's moon Titan did turn out to be blowing in the wind. It just wasn't from the direction many scientists expected.

Basic principles describing the rotation of planetary atmospheres and data from the European Space Agency's Huygens probe led to circulation models that showed surface winds streaming generally east-to-west around Titan's equatorial belt. But when NASA's Cassini spacecraft obtained the first images of dunes on Titan in 2005, the dunes' orientation suggested the sands – and therefore the winds – were moving from the opposite direction, or west to east.

A new paper by Tetsuya Tokano in press with the journal Aeolian Research seeks to explain the paradox. It explains that seasonal changes appear to reverse wind patterns on Titan for a short period. These gusts, which occur intermittently for perhaps two years, sweep west to east and are so strong they do a better job of transporting sand than the usual east-to-west surface winds. Those east-to-west winds do not appear to gather enough strength to move significant amounts of sand.

A related perspective article about Tokano's work by Cassini radar scientist Ralph Lorenz, the lead author on a 2009 paper mapping the dunes, appears in this week's issue of the journal Science.

"It was hard to believe that there would be permanent west-to-east winds, as suggested by the dune appearance," said Tokano, of the University of Cologne, Germany. "The dramatic, monsoon-type wind reversal around equinox turns out to be the key."

Cassini radar sees sand dunes on Saturn's giant moon Titan (upper photo) that are sculpted like Namibian sand dunes on Earth (lower photo). The bright features in the upper radar photo are not clouds but topographic features among the dunes. Image credit: NASA/JPL - upper photo; NASA/JSC - lower photo

The dunes track across the vast sand seas of Titan only in latitudes within 30 degrees of the equator. They are about a kilometer (half a mile) wide and tens to hundreds of kilometers (miles) long. They can rise more than 100 meters (300 feet) high. The sands that make up the dunes appear to be made of organic, hydrocarbon particles. The dunes' ridges generally run west-to-east, as wind here generally sheds sand along lines parallel to the equator.

Scientists predicted winds in the low latitudes around Titan's equator would blow east-to-west because at higher latitudes the average wind blows west-to-east. The wind forces should balance out, based on basic principles of rotating atmospheres.

Tokano re-analyzed a computer-based global circulation model for Titan he put together in 2008. That model, like others for Titan, was adapted from ones developed for Earth and Mars. Tokano added in new data on Titan topography and shape based on Cassini radar and gravity data. In his new analysis, Tokano also looked more closely at variations in the wind at different points in time rather than the averages. Equinox periods jumped out.

Equinoxes occur twice a Titan year, which is about 29 Earth years. During equinox, the sun shines directly over the equator, and heat from the sun creates upwelling in the atmosphere. The turbulent mixing causes the winds to reverse and accelerate. On Earth, this rare kind of wind reversal happens over the Indian Ocean in transitional seasons between monsoons.

The episodic reverse winds on Titan appear to blow around 1 to 1.8 meters per second (2 to 4 mph). The threshold for sand movement appears to be about 1 meter per second (2 mph), a speed that the typical east-to-west winds never appear to surpass. Dune patterns sculpted by strong, short episodes of wind can be found on Earth in the northern Namib sand seas in Namibia, Africa.

Scientists have used data from the Cassini radar mapper to map the global wind pattern on Saturn's moon Titan using data collected over a four-year period, as depicted in this image. Image credit: NASA/JPL/Space Science Institute

"This is a subtle discovery -- only by delving into the statistics of the winds in the model could this rather distressing paradox be resolved," said Ralph Lorenz, a Cassini radar scientist based at the Johns Hopkins University Applied Physics Laboratory in Laurel, Md. "This work is also reassuring for preparations for proposed future missions to Titan, in that we can become more confident in predicting the winds which can affect the delivery accuracy of landers, or the drift of balloons."

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. JPL manages the Cassini-Huygens mission for NASA's Science Mission Directorate. The Cassini orbiter was designed, developed and assembled at JPL. The radar instrument was built by JPL and the Italian Space Agency, working with team members from the United States and several European countries. JPL is a division of the California Institute of Technology in Pasadena.

More Cassini information is available, at http://www.nasa.gov/cassini and http://saturn.jpl.nasa.gov.

For more information visit http://www.nasa.gov/mission_pages/cassini/whycassini/cassini20100729.html

GRAIL Spacecraft Takes Shape

Engineers have conducted a fuel tank check of one of NASA's GRAIL mission spacecraft (Gravity Recovery and Interior Laboratory), scheduled for launch in 2011. Confirming the size and fit of manufactured components is one of the steps required prior to welding the spacecraft's fuel tanks into the propulsion system's feed lines.

The image was taken on June 29, 2010, during the propulsion subsystem assembly and integration effort in the Space Support Building clean room at Lockheed Martin Space Systems in Denver.

Engineers conduct checks on one of NASA's GRAIL spacecraft in the Space Support Building at Lockheed Martin Space Systems in Denver. Image credit: NASA/JPL/LockheedMartin

The GRAIL mission will fly twin spacecraft (spacecraft "A" and "B") in tandem orbits around the moon for several months to measure its gravity field in unprecedented detail. The mission will also answer longstanding questions about Earth's moon, and provide scientists a better understanding of how Earth and other rocky planets in the solar system formed.

For more information about GRAIL, please visit: http://moon.mit.edu/ .

For more information visit http://www.nasa.gov/topics/moonmars/features/grail20100728.html

NASA Spacecraft Camera Yields Most Accurate Mars Map Ever

PASADENA, Calif. -- A camera aboard NASA's Mars Odyssey spacecraft has helped develop the most accurate global Martian map ever. Researchers and the public can access the map via several websites and explore and survey the entire surface of the Red Planet.

The map was constructed using nearly 21,000 images from the Thermal Emission Imaging System, or THEMIS, a multi-band infrared camera on Odyssey. Researchers at Arizona State University's Mars Space Flight Facility in Tempe, in collaboration with NASA's Jet Propulsion Laboratory in Pasadena, Calif., have been compiling the map since THEMIS observations began eight years ago.

The pictures have been smoothed, matched, blended and cartographically controlled to make a giant mosaic. Users can pan around images and zoom into them. At full zoom, the smallest surface details are 100 meters (330 feet) wide. While portions of Mars have been mapped at higher resolution, this map provides the most accurate view so far of the entire planet.

The new map is available at: http://www.mars.asu.edu/maps/?layer=thm_dayir_100m_v11 .

Advanced users with large bandwidth, powerful computers and software capable of handling images in the gigabyte range can download the full-resolution map in sections at: http://www.mars.asu.edu/data/thm_dir_100m .

Valles Marineris, the "Grand Canyon of Mars," sprawls wide enough to reach from Los Angeles to nearly New York City, if it were located on Earth. The red outline box shows the location of a second, full-resolution image. Credit: NASA/JPL/Arizona State University

"We've tied the images to the cartographic control grid provided by the U.S. Geological Survey, which also modeled the THEMIS camera's optics," said Philip Christensen, principal investigator for THEMIS and director of the Mars Space Flight Facility. "This approach lets us remove all instrument distortion, so features on the ground are correctly located to within a few pixels and provide the best global map of Mars to date."

Working with THEMIS images from the new map, the public can contribute to Mars exploration by aligning the images to within a pixel's accuracy at NASA's "Be a Martian" website, which was developed in cooperation with Microsoft Corp. Users can visit the site at: http://beamartian.jpl.nasa.gov/maproom#/MapMars .

"The Mars Odyssey THEMIS team has assembled a spectacular product that will be the base map for Mars researchers for many years to come," said Jeffrey Plaut, Odyssey project scientist at JPL. "The map lays the framework for global studies of properties such as the mineral composition and physical nature of the surface materials."

Other sites build upon the base map. At Mars Image Explorer, which includes images from every Mars orbital mission since the mid-1970s, users can search for images using a map of Mars at: http://themis.asu.edu/maps .

"The broad purpose underlying all these sites is to make Mars exploration easy and engaging for everyone," Christensen said. "We are trying to create a user-friendly interface between the public and NASA's Planetary Data System, which does a terrific job of collecting, validating and archiving data."

This image shows a 90-mile-wide portion of the giant Valles Marineris canyon system. Landslide debris and gullies in the canyon walls on Mars can be seen at 100 meters (330 feet) per pixel. Credit: NASA/JPL/Arizona State University

Mars Odyssey was launched in April 2001 and reached the Red Planet in October 2001. Science operations began in February 2002. The mission is managed by JPL for NASA's Science Mission Directorate in Washington. Lockheed Martin Space Systems in Denver is the prime contractor for the project and built the spacecraft. NASA's Planetary Data System, sponsored by the Science Mission Directorate, archives and distributes scientific data from the agency's planetary missions, astronomical observations, and laboratory measurements.

For more information about NASA's Odyssey spacecraft, visit: http://mars.jpl.nasa.gov/odyssey .

JPL is managed for NASA by the California Institute of Technology in Pasadena.

For more information visit http://www.nasa.gov/mission_pages/odyssey/odyssey20100723.html

See Beautiful Ontario Lacus: Cassini's Guided Tour

Ontario Lacus, the largest lake in the southern hemisphere of Saturn's moon Titan, turns out to be a perfect exotic vacation spot, provided you can handle the frosty, subzero temperatures and enjoy soaking in liquid hydrocarbon.

Several recent papers by scientists working with NASA's Cassini spacecraft describe evidence of beaches for sunbathing in Titan's low light, sheltered bays for mooring boats, and pretty deltas for wading out in the shallows. They also describe seasonal changes in the lake's size and depth, giving vacationers an opportunity to visit over and over without seeing the same lake twice. (Travel agents, of course, will have to help you figure out how to breathe in an atmosphere devoid of oxygen.)

Using data that give us the most detailed picture yet of a lake on another world, scientists and animators have collaborated on a new video tour of Ontario Lacus based on radar data from Cassini's Titan flybys on June 22, 2009, July 8, 2009, and Jan. 12, 2010. A Web video explaining how scientists look to Earth's Death Valley to understand places like Titan's Ontario Lacus is available at: http://www.nasa.gov/multimedia/videogallery/index.html?collection_id=14658&media_id=16290407

"With such frigid temperatures and meager sunlight, you wouldn't think Titan has a lot in common with our own Earth," said Steve Wall, deputy team lead for the Cassini radar team, based at NASA's Jet Propulsion Laboratory in Pasadena, Calif. "But Titan continues to surprise us with activity and seasonal processes that look marvelously, eerily familiar."

Cassini arrived at Saturn in 2004 when the southern hemisphere of the planet and its moons were experiencing summer. The seasons have started to change toward autumn, with winter solstice darkening the southern hemisphere of Titan in 2017. A year on Titan is the equivalent of about 29 Earth years.

This image of Ontario Lacus, the largest lake on the southern hemisphere of Saturn's moon Titan, was obtained by NASA's Cassini spacecraft on Jan. 12, 2010. Image Credit: NASA/JPL-Caltech

Titan is the only other world in our solar system known to have standing bodies of liquid on its surface. Because surface temperatures at the poles average a chilly 90 Kelvin (about minus 300 degrees Fahrenheit), the liquid is a combination of methane, ethane and propane, rather than water. Ontario Lacus has a surface area of about 15,000 square kilometers (6,000 square miles), slightly smaller than its terrestrial namesake Lake Ontario.

Cassini first obtained an image of Ontario Lacus with its imaging camera in 2004. A paper submitted to the journal Icarus by Alex Hayes, a Cassini radar team associate at the California Institute of Technology in Pasadena, and colleagues finds that the lake's shoreline has receded by about 10 kilometers (6 miles). This has resulted in a liquid level reduction of about 1 meter (3 feet) per year over a four–year period.

The shoreline appears to be receding because of liquid methane evaporating from the lake, with a total amount of evaporation that would significantly exceed the yearly methane gas output of all the cows on Earth, Hayes said. Some of the liquid could also seep into porous ground material. Hayes said the changes in the lake are likely occurring as part of Titan's seasonal methane cycle, and would be expected to reverse during southern winter.

This seasonal filling and receding is similar to what occurs at the shallow lakebed known as Racetrack Playa in Death Valley National Park, Hayes said. In fact, from the air, the topography and shape of Racetrack Playa and Ontario Lacus are quite similar, although Ontario Lacus is about 60 times larger.

"We are very excited about these results, because we did not expect Cassini to be able to detect changes of this magnitude in Titan's lakes," Hayes said. "It is only through the continued monitoring of seasonal variation during Cassini's extended mission that these discoveries have been made possible."

Other parts of the Ontario Lacus' shoreline, as described in the paper published in Geophysical Research Letters in March 2010 by Wall, Hayes and other colleagues, show flooded valleys and coasts, further proof that the lake level has changed.

The delta revealed by Cassini radar data on the western shore of Ontario Lacus is also the first well-developed delta observed on Titan, Wall said. He explained that the shape of the land there shows liquid flowing down from a higher plain switching channels on its way into the lake, forming at least two lobes.

Examples of this kind of channel switching and wave-modified deltas can be found on Earth at the southern end of Lake Albert between Uganda and the Democratic Republic of Congo in Africa, and the remains of an ancient lake known as Megachad in the African country Chad, Wall said.

The radar data also show a smooth beach on the northwestern shore of Ontario Lacus. Smooth lines parallel to the current shoreline could be formed by low waves over time, which were likely driven by winds sweeping in from the west or southwest. The pattern at Ontario Lacus resembles what might be seen on the southeastern side of Lake Michigan, where waves sculpt the shoreline in a similar fashion.

"Cassini continues to take our breath away as it fills in the details on the surfaces of these far-off moons," said Linda Spilker, Cassini project scientist based at JPL. "It's exhilarating to ride along as it takes us on the ultimate cold-weather adventure."

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. JPL manages the Cassini-Huygens mission for NASA's Science Mission Directorate. The Cassini orbiter was designed, developed and assembled at JPL. The radar instrument was built by JPL and the Italian Space Agency, working with team members from the United States and several European countries.

More Cassini information is available, at http://www.nasa.gov/cassini, http://saturn.jpl.nasa.gov.

For more information visit http://www.nasa.gov/mission_pages/cassini/whycassini/cassini20100715.html

Saturn System Moves Oxygen From Enceladus to Titan

Complex interactions between Saturn and its satellites have led scientists using NASA's Cassini spacecraft to a comprehensive model that could explain how oxygen may end up on the surface of Saturn's icy moon Titan. The presence of these oxygen atoms could potentially provide the basis for pre-biological chemistry.

The interactions are captured in two papers, one led by John Cooper and another led by Edward Sittler, published in the journal Planetary and Space Science in late 2009. Cooper and Sittler are Cassini plasma spectrometer team scientists at NASA's Goddard Space Flight Center in Greenbelt, Md.

"Titan and Enceladus, another icy moon of Saturn, are chemically connected by the flow of material through the Saturn system," Cooper said.

In one paper, Cooper and colleagues provide an explanation for forces that could generate the Enceladus geysers that spew water vapor into space. In the other, published in the same issue, Sittler and colleagues describe a unique new process in which oxygen that circulates in the upper atmosphere of Titan can be carried all the way to the surface without further chemical contamination by being encased in carbon cages called fullerenes.

The work draws upon previous work by Sittler and others that model the dynamics of how particles, including water molecules, travel from Enceladus to Titan. At Enceladus the flow process begins with what they call the "Old Faithful" model, after the Old Faithful geyser in Yellowstone National Park. In this model, gas pressure slowly builds up inside Enceladus, then gets released occasionally in geyser-like eruptions.

Unlike terrestrial geysers, or even geyser-like forces on Jupiter's moon Io, the model proposed by Cooper shows that charged particle radiation raining down from Saturn’s magnetosphere can create the forces from below the surface that are required to eject gaseous jets.

Energetic particles raining down from Saturn's magnetosphere – at Enceladus, mostly electrons from Saturn's radiation belts -- can break up molecules within the surface. This process is called radiolysis. Like a process called photolysis, in which sunlight can break apart molecules in the atmosphere, energetic radiation from charged particles that hit an icy surface, like that of Enceladus, can cause damage to molecules within the ice. These damaged molecules can get buried deeper and deeper under the surface by the perpetual churning forces that can repave the icy surface. Meteorites constantly crashing into the surface and splashing out material might also be burying the molecules.

This annotated image collage features Saturn and the moons Titan, Enceladus, Dione, Rhea and Helene, which are being studied by the Cassini mission. Image credit: NASA/JPL/Space Science Institute

When chemically altered icy grains come into contact beneath the surface with icy contaminants such as ammonia, methane and other hydrocarbons, they can produce volatile gases that can explode outward. Such gases can create plumes of the size seen by Cassini. Cooper and colleagues call such icy volatile mechanics "cryovolcanism."

What's unique about the "Old Faithful" model is that it "is a model for cryovolcanism that is based on not only liquid water, but also requires the production of gases by the radiolytic chemistry observed at Enceladus," said Sittler.

The plumes that emanate from Enceladus' south polar region consist of water, ammonia and other compounds. Scientists have known since the 1980s that Saturn's magnetosphere is inexplicably filled with neutral particles. In the intervening decades, particularly since the discovery of plumes jetting out from the south pole of Enceladus, work has shown how some of the water molecules that escape from Enceladus get split up into neutral and charged particles and are transported throughout Saturn's magnetosphere.

Sittler's new model indicates that as these broken water molecules enter Titan's atmosphere, they may be captured by fullerenes—hollow, soccer-ball shaped shells made of carbon atoms. Although the heavy molecules Cassini has detected in the upper atmosphere of Titan may be other molecules, Sittler suggests they are likely fullerenes.

In Sittler's model, the fullerenes then condense into larger clusters that can attach to polycyclic aromatic hydrocarbons—chemical compounds also found on Earth in oil, coal and tar deposits, and as the byproducts of burning fossil fuels. The fullerene clusters form even larger aerosols that travel down to Titan's surface.

This process protects the trapped oxygen from Titan's atmosphere, which is saturated with hydrogen atoms and compounds that are capable of breaking down other molecules. Otherwise, the oxygen would combine with methane in Titan's atmosphere and form carbon monoxide or carbon dioxide. Until now, scientists have not been able to explain how oxygen fits into the picture of the dynamics and chemistry of Saturn and its moons.

As the oxygen-rich aerosols fall to Titan's surface, they are further bombarded by products of galactic cosmic ray interactions with Titan's atmosphere. Cosmic rays bombarding the oxygen-stuffed fullerenes could produce more complex organic materials, such as amino acids, in the carbon-rich and oxygen-loaded fullerenes. Amino acids are considered important for pre-biological chemistry.

Scientists have been able to couple the new models that describe the generation of plumes at Enceladus and oxygen ion capture in fullerenes near the top of Titan's atmosphere to existing theories of the transport of oxygen across the magnetosphere. Taken together, Sittler and Cooper suggest a chemical pathway that allows the oxygen to be introduced to Titan's surface chemistry.

"Cooper and Sittler's work helps us understand more about the potential for chemical interactions among Saturn's moons," said Linda Spilker, Cassini project scientist at NASA's Jet Propulsion Laboratory in Pasadena, Calif.

"The Saturn system is indeed a dynamic place, with the Enceladus plumes creating the E ring and loading the magnetosphere with water which interacts with Titan and the other moons," Spilker said.

The Cassini mission is a joint effort of NASA, the European Space Agency, and the Italian space agency Agenzia Spaziale Italiana. The mission is managed for NASA by the Jet Propulsion Laboratory, a division of the California Institute of Technology. Partners include the U.S. Air Force, Department of Energy, and academic and industrial participants from 19 countries.

For more information visit http://www.nasa.gov/mission_pages/cassini/whycassini/saturn20100701.html

Tile Testing

In Orbiter Processing Facility-3 at NASA’s Kennedy Space Center in Florida, United Space Alliance tile technician Jimmy Carter works on boundary layer transition tile bonding on space shuttle Discovery's leading wing edge.

The boundary layer transition tiles are part of testing designed to help engineers better understand the heating environment around a spacecraft as it reenters the atmosphere.

Discovery and its crew for the STS-133 mission are targeted to deliver the Express Logistics Carrier-4 filled with external payloads and experiments, as well as critical spare components to the International Space Station.

Image credit: NASA/Frankie Martin
June 25, 2010

For more information visit http://www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/multimedia/gallery/10-06-25.html

Next Mars Rover Sports a Set of New Wheels

PASADENA, Calif. – NASA's next Mars rover, Curiosity, is sitting pretty on a set of spiffy new wheels that would be the envy of any car show on Earth.

The wheels and a suspension system were added this week by spacecraft technicians and engineers. These new and important touches are a key step in assembling and testing the flight system in advance of a planned 2011 launch.

Mars rover Curiosity, the centerpiece of NASA's Mars Science Laboratory mission, is coming together for extensive testing prior to its late 2011 launch. Image Credit: NASA/JPL-Caltech

Curiosity, centerpiece of NASA's Mars Science Laboratory mission, is a six-wheeler and uses a rocker-bogie suspension system like its smaller predecessors: Spirit, Opportunity and Sojourner. Each wheel has its own drive motor, and the corner wheels also have independent steering motors. Unlike earlier Mars rovers, Curiosity will also use its mobility system as a landing gear when the mission's rocket-powered descent stage lowers the rover directly onto the Martian surface on a tether in August 2012.

In coming months at NASA's Jet Propulsion Laboratory, the mobility system will get functional testing and be part of environmental testing of the rover. The mobility system will now stay on Curiosity through launch unless testing identifies a need for rework that would require it to be disassembled.

With the wheels and suspension system already installed onto one side of NASA's Mars rover Curiosity the previous day, spacecraft engineers and technicians prepare the other side's mobility subsystem for installation on June 29, 2010. Image Credit: NASA/JPL-Caltech

The mission will launch from Florida during the period Nov. 25 to Dec. 18, 2011. Curiosity will examine an area of Mars for modern or ancient habitable environments, including any that may have also been favorable for preserving clues about life and environment, though this mission will not seek evidence of life. It will examine rocks, soil and atmosphere with a diverse payload of tools, including a laser to vaporize patches of rock from a distance and an instrument designed to test for organic compounds.

For more information visit http://www.nasa.gov/mission_pages/msl/msl20100701.html

NASA Retires TRACE Spacecraft After Highly Successful Mission

NASA's Transition Region And Coronal Explorer, known as TRACE, conducted its final observations of the sun on June 21.

Although launched on April Fools' Day, 1998, TRACE quickly proved its worth, observing – for the first time - an entire cycle of solar activity and imaging dynamic coronal phenomena.

TRACE provided images at five times the magnification of those taken by the Extreme Ultraviolet Imaging Telescope Instrument aboard the Solar and Heliospheric Observatory (SOHO).

TRACE spacecraft from video

Many details of the fine structure of the corona were observed for the first time. Early in its mission, it discovered the fine-scale magnetic features where enhanced heating occurs at the footpoints of coronal loop systems in solar active regions, which later became known as "coronal moss."

In 2001, TRACE observations of astonishing coronal activity were highlighted in the IMAX movie SolarMax.

High spatial resolution observations of the solar corona are now being carried out by NASA''s newest eye on the sun, the Solar Dynamics Observatory, a Goddard-built spacecraft managed by the Science Mission Directorate's Heliophysics Division. SDO's field of view is much larger than TRACE, so that the entire disk of the sun, not a small area, is imaged in every observation.

The TRACE spacecraft observes an X-ray flare over solar active region AR9906, April 21, 2002.

Lockheed-Martin Solar and Astrophysics Laboratory in Palo Alto, Calif., developed the TRACE instrument and NASA Goddard Space Flight Center's Flight Projects Directorate designed and built this Small Explorer class spacecraft. The entire mission was accomplished for $10M under budget.

During its 12 year mission, TRACE produced millions of stunning images and contributed to more than 1,000 scientific publications.

Congratulations to TRACE mission team and numerous other scientists and engineers who contributed the mission’s outstanding success.

For more information visit http://www.nasa.gov/topics/solarsystem/sunearthsystem/main/trace-retires.html

Voyager 2 at 12,000 Days: The Super-Marathon Continues

NASA's plucky Voyager 2 spacecraft has hit a long-haul operations milestone today (June 28) -- operating continuously for 12,000 days. For nearly 33 years, the venerable spacecraft has been returning data about the giant outer planets, and the characteristics and interaction of solar wind between and beyond the planets. Among its many findings, Voyager 2 discovered Neptune's Great Dark Spot and its 450-meter-per-second (1,000-mph) winds.

The two Voyager spacecraft have been the longest continuously operating spacecraft in deep space. Voyager 2 launched on August 20, 1977, when Jimmy Carter was president. Voyager 1 launched about two weeks later on Sept. 5. The two spacecraft are the most distant human-made objects, out at the edge of the heliosphere -- the bubble the sun creates around the solar system. Mission managers expect Voyager 1 to leave our solar system and enter interstellar space in the next five years or so, with Voyager 2 on track to enter interstellar space shortly after that.

This artist's rendering depicts NASAs Voyager 2 spacecraft as it studies the outer limits of the heliosphere - a magnetic 'bubble' around the solar system that is created by the solar wind. Image credit: NASA/JPL-Caltech.

Having traveled more than 21 billion kilometers (13 billion miles) on its winding path through the planets toward interstellar space, the spacecraft is now nearly 14 billion kilometers (9 billion miles) from the sun. A signal from the ground, traveling at the speed of light, takes about 12.8 hours one-way to reach Voyager 2.

This image of the official Voyager clock, taken today, June 28, 2010, at NASA's Jet Propulsion Laboratory, shows that NASA's Voyager 2 spacecraft has been operating continuously for 12,000 days. The Voyager clock is kept at JPL. Image Credit: NASA/JPL-Caltech.

Voyager 1 will reach this 12,000-day milestone on July 13, 2010 after traveling more than 22 billion kilometers (14 billion miles). Voyager 1 is currently more than 17 billion kilometers (11 billion miles) from the sun.

The Voyagers were built by JPL, which continues to operate both spacecraft. Caltech manages JPL for NASA.

For more information about the Voyagers, visit: http://voyager.jpl.nasa.gov/.

For more information visit http://www.nasa.gov/mission_pages/voyager/voyager20100628.html