Data from a NASA planetary mission have provided scientists evidence of what appears to be a body of liquid water, equal in volume to the North American Great Lakes, beneath the icy surface of Jupiter’s moon, Europa.

The data suggest there is significant exchange between Europa’s icy shell and the ocean beneath. This information could bolster arguments that Europa’s global subsurface ocean represents a potential habitat for life elsewhere in our solar system. The findings are published in the scientific journal Nature.

“The data opens up some compelling possibilities,” said Mary Voytek, director of NASA’s Astrobiology Program at agency headquarters in Washington. “However, scientists worldwide will want to take a close look at this analysis and review the data before we can fully appreciate the implication of these results.”

NASA’s Galileo spacecraft, launched by the space shuttle Atlantis in 1989 to Jupiter, produced numerous discoveries and provided scientists decades of data to analyze. Galileo studied Jupiter, which is the most massive planet in the solar system, and some of its many moons.

One of the most significant discoveries was the inference of a global salt water ocean below the surface of Europa. This ocean is deep enough to cover the whole surface of Europa and contains more liquid water than all of Earth’s oceans combined. However, being far from the sun, the ocean surface is completely frozen. Most scientists think this ice crust is tens of miles thick.

“One opinion in the scientific community has been if the ice shell is thick, that’s bad for biology. That might mean the surface isn’t communicating with the underlying ocean,” said Britney Schmidt, lead author of the paper and postdoctoral fellow at the Institute for Geophysics, University of Texas at Austin. “Now, we see evidence that it’s a thick ice shell that can mix vigorously and new evidence for giant shallow lakes. That could make Europa and its ocean more habitable.”

Schmidt and her team focused on Galileo images of two roughly circular, bumpy features on Europa’s surface called chaos terrains. Based on similar processes seen on Earth — on ice shelves and under glaciers overlaying volcanoes — they developed a four-step model to explain how the features form. The model resolves several conflicting observations. Some seemed to suggest the ice shell is thick. Others suggest it is thin.

This recent analysis shows the chaos features on Europa’s surface may be formed by mechanisms that involve significant exchange between the icy shell and the underlying lake. This provides a mechanism or model for transferring nutrients and energy between the surface and the vast global ocean already inferred to exist below the thick ice shell. This is thought to increase the potential for life there.

The study authors have good reason to believe their model is correct, based on observations of Europa from Galileo and of Earth. Still, because the inferred lakes are several miles below the surface, the only true confirmation of their presence would come from a future spacecraft mission designed to probe the ice shell. Such a mission was rated as the second highest priority flagship mission by the National Research Council’s recent Planetary Science Decadal Survey and is being studied by NASA.

“This new understanding of processes on Europa would not have been possible without the foundation of the last 20 years of observations over Earth’s ice sheets and floating ice shelves,” said Don Blankenship, a co-author and senior research scientist at the Institute for Geophysics, where he leads airborne radar studies of the planet’s ice sheets.

Galileo was the first spacecraft to directly measure Jupiter’s atmosphere with a probe and conduct long-term observations of the Jovian system. The probe was the first to fly by an asteroid and discover the moon of an asteroid. NASA extended the mission three times to take advantage of Galileo’s unique science capabilities, and it was put on a collision course into Jupiter’s atmosphere in September 2003 to eliminate any chance of impacting Europa.

The Galileo mission was managed by NASA’s Jet Propulsion Laboratory in Pasadena, Calif., for the agency’s Science Mission Directorate.

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Saturn’s moon Enceladus shows its icy face and famous plumes in raw, unprocessed images captured by NASA’s Cassini spacecraft during its successful flyby on Nov. 6, 2011.

During this Enceladus encounter, the 16th of Cassini’s mission, the spacecraft passed the moon at distance of about 300 miles (500 kilometers) at 10:11 p.m. PDT on Nov. 5 (04:49 UTC on Nov. 6).

To see the raw images, go to http://saturn.jpl.nasa.gov/photos/raw/ and click on “Search Images.”

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Part of human fascination with space is the chance to look back at our own planet from afar. The unique vantage from the International Space Station affords a vista both breathtaking and scientifically illuminating.

Here on Earth, both scientists and spectators rely on the station’s crew to record and transmit images and videos of what they see to share in their experience. Until recently, reduced lighting conditions at night, combined with insufficiently perceptive equipment, made some of the most beautiful views difficult to capture.

This changed with the arrival of the Super Sensitive High Definition TV, or SS-HDTV, camera on the space station. With the SS-HDTV, the crew can document new and more detailed footage of the dynamic interactions that take place in the area between the Earths’ atmosphere and the vacuum of space, known as the cosmic shore.

According to Keiji Murakami, a senior engineer with the Japan Aerospace Exploration Agency, or JAXA, this camera’s superior recording capability opens up a significant window of observation. Some may not realize that the station orbits the Earth 16 times a day, experiencing multiple sunrises and sunsets during those 24 hours. The crew actually has a 50/50 chance of a night view. “Half of the Earth view from [station] is a night view. And the day view and night view are very different,” said Murakami.

By October, JAXA astronaut Satoshi Furukawa had logged more than 30 hours of video using the camera. While the Earth observations are an amazing sight, they are also an important part of the research goals for the space station. From images taken by crew members aboard station, scientists can research natural phenomena and man-made changes to the planet.

Japan Broadcasting Corp., or NHK, which is similar to the U.S.’s Public Broadcasting System, or PBS, aired the first public videos showing the SS-HDTV camera’s capabilities Sept. 18, 2011. The resulting show was appropriately titled “The Cosmic Shore,” and it thrilled audiences with a spectacular view of natural phenomena, such as aurora and lightning. Furukawa filmed and narrated the video footage, which also shared man-made wonders, like the lights of Japan at night, in greater detail than previously possible.

Murakami comments on the merit of the SS-HDTV camera system’s ability to capture momentary phenomena, like meteors and sprites — a form of upper atmospheric lightning. “Using this super sensitive camera, we have observed the lightning, sprite, aurora, meteor, noctilucent cloud and airglow,” said Murakami. “The phenomena of the sprite has not yet been studied in high definition until now. The color video of the sprite was taken for the first time from space using this camera.”

This advanced equipment belongs to JAXA, in cooperation with NHK, and enables recording of the elusive phenomena that occurs within low-light conditions using an Electron Multiplying Charged Coupled Device, or EM-CCD, sensor. After filming, the crew downlinks the videos to the ground using data-relay satellites.

The SS-HDTV also can advance astronomical observations, according to Murakami. This equipment will continue to operate on orbit indefinitely. Even if a failure should occur, there is a backup camera and Panasonic SD card recorder already aboard the station as a precaution. As with many facilities and technology on the space station, this camera provides another asset available to future researchers as they continue to explore the space environment using the orbiting laboratory.

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A lunar sample from a rock that once sat on the surface of the moon will be on public display at Arizona State University (ASU) in Tempe, AZ beginning November 5, 2011.

The golf ball-sized moon rock, on a long-term loan to ASU from NASA, will be on display in the Lunar Reconnaissance Orbiter Camera (LROC) Visitor Gallery on ASU’s Tempe campus.

Weighing 77 grams, or about 2.7 ounces, the lunar sample comes from a larger moon rock that was collected by Apollo 15 astronauts. The parent sample, from which the ASU rock was cut, weighed 9.6 kilograms, or about 21 pounds, and was the largest of the rocks collected during the Apollo 15 geologic traverses.

Informally named after its collector, Apollo 15 astronaut Dave Scott, the “Great Scott” rock was picked up about 13 yards (12 meters) north of the rim of Hadley Rille on August 2, 1971. It is part of the 842 pounds (382 kilograms) of lunar samples collected during six Apollo missions (1969 to 1972), and one of the most intensively studied samples.

Brownish-gray in color, sample 15555 is classified as medium-grained olivine basalt. Basalt is one of the most common types of rocks found on Earth, and is also one of the main lunar rock types. This rock crystallized from magma erupted from the mantle almost 3.3 billion years ago, and is predominantly composed of silicate minerals.

“Documented samples from the moon, or any asteroids and planets, are the key to unlocking how planets form and evolve,” says Mark Robinson, professor in the School of Earth and Space Exploration in ASU’s College of Liberal Arts and Sciences. “The moon is especially interesting because it preserves a record of the early solar system that you simply can’t find on Earth, since plate tectonics and fluvial erosion have mostly erased Earth’s early geologic history. Most lunar rocks are older than the oldest Earth rocks found to date. Thus the moon can help scientists go back into the early stages of planet formation. However, it is fascinating to remember that it appears that some of the areas Apollo astronauts did not sample are relatively young, perhaps as young as 500 million years. What will we learn from these younger lunar rocks? A fascinating question left to the next generation of lunar explorers.”

The ASU moon rock is encased in a triangular NASA-prepared airtight glass case that is filled with inert gas to protect the sample from the terrestrial environment. It resides in a protective alcove encapsulated in a specially designed display secured by multiple levels of security. The display’s creator, Chris Skiba, a research professional in the School of Earth and Space Exploration, was asked to design a display worthy of showcasing a priceless national treasure. Skiba stated that he had seen many lunar sample displays and wanted to “kick it up a notch” so the public could experience the sample in 360 degrees.

The moon rocks sits on top of a quartz plate, attached to a polished stainless steel stage that rotates displaying all sides of the moon rock. According to Skiba, this might be the only Apollo 15 lunar sample that rotates for public viewing.

“It is almost like you are holding it yourself and experiencing all sides of the moon rock,” says Skiba.

Skiba utilized the effects of the quartz and how it can transmit light. The quartz plate is illuminated by a blue LED that creates a stunning blue ring of light around the sample.

Several Apollo lunar samples are on long-term loan for public displays around the world. Display samples are historically allocated to major museums with relevant content, or places with a current or historical connection to lunar exploration. Mark Robinson is the principal investigator of the Lunar Reconnaissance Orbiter Camera (LROC) on board the Lunar Reconnaissance Orbiter (LRO) spacecraft. Key goals of the LRO mission are to collect comprehensive data sets on fifty scientifically intriguing sites, identification of lunar resources, studies of how the lunar radiation environment will affect humans, and answering fundamental lunar science questions.

The LRO spacecraft is managed by NASA’s Goddard Space Flight Center in Greenbelt, Md., for NASA’s Science Mission Directorate in Washington.

Sample Unveiling

The moon rock will be unveiled in the LROC Visitor Gallery on November 5. The LROC Visitor Gallery also features “The Lunar History Walk” hallway exhibit and additional interpretive exhibits in the Science Operations Center (SOC). The SOC handles the planning, targeting and data processing activities associated with the LRO camera, and is designed so that guests can observe the scientists at work behind a glass wall.

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New observations by NASA’s Wide-field Infrared Survey Explorer, or WISE, show there are significantly fewer near-Earth asteroids in the mid-size range than previously thought. The findings also indicate NASA has found more than 90 percent of the largest near-Earth asteroids, meeting a goal agreed to with Congress in 1998.

Astronomers now estimate there are roughly 19,500 — not 35,000 — mid-size near-Earth asteroids. Scientists say this improved understanding of the population may indicate the hazard to Earth could be somewhat less than previously thought. However, the majority of these mid-size asteroids remain to be discovered. More research also is needed to determine if fewer mid-size objects (between 330 and 3,300-feet wide) also mean fewer potentially hazardous asteroids, those that come closest to Earth.

The results come from the most accurate census to date of near-Earth asteroids, the space rocks that orbit within 120 million miles (195 million kilometers) of the sun into Earth’s orbital vicinity. WISE observed infrared light from those in the middle to large-size category. The survey project, called NEOWISE, is the asteroid-hunting portion of the WISE mission. Study results appear in the Astrophysical Journal.

“NEOWISE allowed us to take a look at a more representative slice of the near-Earth asteroid numbers and make better estimates about the whole population,” said Amy Mainzer, lead author of the new study and principal investigator for the NEOWISE project at NASA’s Jet Propulsion Laboratory in Pasadena, Calif. “It’s like a population census, where you poll a small group of people to draw conclusions about the entire country.”

WISE scanned the entire celestial sky twice in infrared light between January 2010 and February 2011, continuously snapping pictures of everything from distant galaxies to near-Earth asteroids and comets. NEOWISE observed more than 100 thousand asteroids in the main belt between Mars and Jupiter, in addition to at least 585 near Earth.

WISE captured a more accurate sample of the asteroid population than previous visible-light surveys because its infrared detectors could see both dark and light objects. It is difficult for visible-light telescopes to see the dim amounts of visible-light reflected by dark asteroids. Infrared-sensing telescopes detect an object’s heat, which is dependent on size and not reflective properties.

Though the WISE data reveal only a small decline in the estimated numbers for the largest near-Earth asteroids, which are 3,300 feet (1 kilometer) and larger, they show 93 percent of the estimated population have been found. This fulfills the initial “Spaceguard” goal agreed to with Congress. These large asteroids are about the size of a small mountain and would have global consequences if they were to strike Earth. The new data revise their total numbers from about 1,000 down to 981, of which 911 already have been found. None of them represents a threat to Earth in the next few centuries. It is believed that all near-Earth asteroids approximately 6 miles (10 kilometers) across, as big as the one thought to have wiped out the dinosaurs, have been found.

“The risk of a really large asteroid impacting the Earth before we could find and warn of it has been substantially reduced,” said Tim Spahr, the director of the Minor Planet Center at the Harvard Smithsonian Center for Astrophysics in Cambridge, Mass.

The situation is different for the mid-size asteroids, which could destroy a metropolitan area if they were to impact in the wrong place. The NEOWISE results find a larger decline in the estimated population for these bodies than what was observed for the largest asteroids. So far, the Spaceguard effort has found and is tracking more than 5,200 near-Earth asteroids 330 feet or larger, leaving more than an estimated 15,000 still to discover. In addition, scientists estimate there are more than a million unknown smaller near-Earth asteroids that could cause damage if they were to impact Earth.

“NEOWISE was just the latest asset NASA has used to find Earth’s nearest neighbors,” said Lindley Johnson, program executive for the Near Earth Object Observation Program at NASA Headquarters in Washington. “The results complement ground-based observer efforts over the past 12 years. These observers continue to track these objects and find even more.”

WISE is managed and operated by JPL for NASA’s Science Mission Directorate in Washington. The principal investigator, Edward Wright, is at the University of California, Los Angeles. The WISE science instrument was built by the Space Dynamics Laboratory in Logan, Utah, and the spacecraft was built by Ball Aerospace and Technologies Corp. in Boulder, Colo. Science operations and data processing occur at the Infrared Processing and Analysis Center at the California Institute of Technology.

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NASA’s Cassini spacecraft successfully completed its Oct. 1 flyby of Saturn’s moon Enceladus and its jets of water vapor and ice. At its closest approach, the spacecraft flew approximately 62 miles (100 kilometers) above the moon’s surface. The close approach was designed to give some of Cassini’s instruments, including the ion and neutral mass spectrometer, the chance to “taste” the jets themselves.

At a higher vantage point during the encounter, Cassini’s high-resolution camera captured pictures of the jets emanating from the moon’s south polar region. The latest raw images of Enceladus are online at: http://saturn.jpl.nasa.gov/photos/raw/ .

The images of the surface include previously seen leading-hemisphere terrain. However, during this encounter, multi-spectral imaging of these terrains extended farther into the ultraviolet region of the electromagnetic spectrum than had previously been achieved at this resolution. By looking at the surface at ultraviolet wavelengths, scientists can better detect the difference between surface materials and shadows than they can at visible wavelengths, where icy materials are highly reflective and shadows are washed out. With both ultraviolet and visible images of the same terrain available to them, scientists will better understand how the surface coverage of icy particles coming from the vents and plumes changes with terrain type and age.

Cassini’s next pass of this fascinating moon will be Oct. 19, when the spacecraft flies by at an altitude of approximately 765 miles (1231 kilometers).

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 mission for NASA’s Science Mission Directorate, Washington. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colo.
The Ion and Neutral Mass Spectrometer science team is based at the Southwest Research Institute, San Antonio, Texas.

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Backpack technology gains traction with astronauts:

After years of chaffing, bruising, and discomfort in some astronauts, running in space just got easier. Whether it’s a two-mile jog or a half-marathon, many astronauts on the International Space Station find their stride and enjoy a relatively pain-free run thanks to the custom-fit, backpack-inspired Glenn Harness.

Because their bones are not under stress or heavy loads in space, astronauts on orbit can suffer a rapid loss of bone mineral density. Without exercise the average monthly loss in astronauts during a six-month stay on the space station is approximately equivalent to the average annual loss that is suffered by post-menopausal women on Earth.

In response, astronauts follow a bone-strengthening routine that includes treadmill running. While the space station has two treadmills, just having the machines available isn’t enough. The microgravity environment of space means astronauts cannot simply step onto a treadmill and jog through a twenty-minute run.

“The only way you can run on a treadmill in space is to have a harness that pulls you back toward the treadmill surface,” said Peter Cavanagh, University of Washington professor and former Director of the Cleveland Clinic’s Center for Space Medicine that developed the new harness design. “What you want ideally is a harness that will apply a force exactly equal to your body weight.”

To provide the mechanical stimulus for healthy bones, the runner needs an impact that represents their full body weight as it is on Earth. Depending on the astronaut, that could be 220 pounds, up to 110 pounds provided by the harness on each side of the body. Compared to the 80- to 90-pound backpack that is considered a heavy load on earth, full body loading is an “extraordinarily difficult loading situation,” according to Gail Perusek, NASA’s Glenn Research Center, Principal Investigator and Project Manager for the Glenn Harness flight studies.

“The torso is basically a cylinder. To get traction you need to apply a downward force. All you have to work with are the shoulders and the hips,” said Perusek. “The original treadmill harness was mostly just Nomex fabric and webbing with minimal padding (Aramid felt). The harness was one-size-fits-all and cumbersome to adjust. It was also inadequate to transfer loads to the hips, where 70-80% of the load should be going.”

Not only did the original harness not transfer loads well, some astronauts found it uncomfortable. One astronaut said the old harness gave him “hot spots.” So he tried using duct tape to protect his skin, leaving him with a few scars. Other astronauts shared his frustration. Crew members complained at times about rubbing, chaffing, and bruising at the shoulders and hips.

Because of the discomfort, astronauts reduced the loads and, as a result, the thinking goes, failed to provide enough stimulus for bone maintenance. Investigating a new design became an obvious direction for the research team.

“Conceptually, the treadmill harness is like a backpack harness. You’re bearing a downward load with the backpack and you’re bearing it on your shoulders and hips. This was a key insight for the research team,” said Sara Novotny, who was a Research Engineer on Cavanagh’s team at the Cleveland Clinic.

The research team went to backpack manufacturers Kelty and Osprey Packs to learn what those companies had done to improve the comfort of carrying heavy loads. The team then selected a mixture of off-the-shelf components from the backpack manufacturers and added some parts of its own to produce a composite harness.

Novotny, a Colorado native who describes the harness as similar to a “backpack without the pack,” assembled the new harnesses that were then used in a number of research studies, including those conducted in NASA Glenn’s Enhanced Zero-gravity Locomotion Simulator, which replicates running on a treadmill in zero gravity.

Ultimately the new experimental Glenn Harnesses were tested aboard the space station in a side-by-side comparison with the operational harnesses. Harnesses equipped with innovative, non-invasive instrumentation provided first-ever insight into how crew members were loading the harnesses in-flight. Crew feedback regarding comfort provided qualitative data, and enthusiasm for the new design.

The collaboration between NASA Glenn and the Cleveland Clinic resulted in the much more comfortable and practical Glenn Harness.

The Glenn Harness has a softer, more malleable interior with a harder exterior, to better distribute loads and avoid hot spots. The hip belt is molded to hug the pelvis, and has a “split feature” to minimize pressure at the hip bones. The shoulder straps are designed in an “S” shape that lets them cut across the chest so they don’t impede the ability to breathe while running under a heavy load.

The Glenn Harness can be easily adjusted while running and is designed for a custom fit with a range of sizes from small to extra large in both female and male versions. The harness sizes can be blended as necessary. For example, a large shoulder strap can be combined with a medium waist strap for a perfect fit. A more recent development is a newer shoulder-strap design specifically for women.

With the new harness it is possible to adjust how the load is distributed between the shoulders and the hips. The molded waist belt allows for more comfortable distribution of a large load to encourage astronauts to run under a heavier load, a condition believed to be necessary for bone health.

Along with the custom fitting, another reason for providing each astronaut with their own harness has to do with the basic feature of a good workout.

“It’s athletic equipment. They sweat in it. The harness never gets washed. They wear these things for the entire six-month increment,” said Perusek.

At the suggestion of one astronaut, the Glenn Harness now employs a biocidal fabric on surfaces where there is contact with the body. This antimicrobial material kills the bacteria that causes odor and causes things to grow. Pre – and post-microbial tests confirm “the stuff works great,” said Perusek.

The new harnesses are endorsed as a crew preference item and are provided by request to the U.S. on orbit segment. They can take up to six months prior to launch to schedule the pre-fit session with the crew member and conduct a crew familiarity briefing. The new harnesses take about eight weeks to assemble and certify before they are ready for use in space. The future plan is to have an inventory of harnesses in stock, and certify them for operational use as the primary treadmill harness for the space station.

The next step is to evaluate whether use of the new harness influences bone health in long duration crew members.

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As the school year kicks off, teachers commonly ask students to share their summer experiences with the class. One might have vacationed with their family, another may have gone camping, but this year there will be a select few who can say that they programmed code that controlled satellites on the International Space Station!

The second annual Zero Robotics Summer SPHERES Program ran for five weeks this past summer. The Synchronized Position Hold, Engage, Reorient Experimental Satellites, or SPHERES, mentioned in the program name are used aboard the station to test guidance, navigation and control in microgravity — when not in use for space competitions.

Astronaut Ron Garan refereed the on-orbit tournament on Aug. 16, 2011. Students watched via live video downlink as the team from Winthrop 21st Century Community Learning Center in Winthrop, Mass. took home first place honors. Other participating Massachusetts schools included Salem CyberSpace in Salem, Robert L. Ford School in Lynn, the East End House in Cambridge and James P. Timilty Middle School in Roxbury.

Zero Robotics Lead 2011 Sreeja Nag explained the appeal for participating students. “It’s like playing video games with real satellites on the space station, except that instead of an X-box or a game controller, students are using computer code for autonomous control,” said Nag.

The goal of this partnership between NASA, the Massachusetts Institute of Technology, or MIT, and the Massachusetts Afterschool Partnership, or MAP, is to ramp up middle school student interest in math, science, technology and engineering. More than 75 students participated this summer, learning problem-solving and design skills. Under the guidance of an MIT undergraduate coach, students worked through a preset curriculum. After covering basic math, science and space concepts, students studied the game and then divided into groups to plan strategies and learn to write code.

MAP Executive Director Kathleen Magrane commented on the success of the collaborative effort. “We want to provide students with complimentary, experiential learning opportunities that connect youth with prominent scientists and encourage them to pursue careers in the fields of science, technology, engineering and/or mathematics,” said Magrane. “Strategic partnerships like these allow us to generate curiosity, build confidence and strengthen the capacity of our young people to achieve greatness, now and in the future.”

This year the competition had half the participants as last year, due to reduced funding. The students learned C Programming, an advanced computer language with specific rules on how the code must be written. Each team paid great attention to their code, as a misplaced colon or parenthesis could mean the difference between a win or loss.

Once uploaded, the code that student teams wrote controlled and directed the SPHERES to achieve the game objectives aboard the station. This summer’s specific challenge was to provide a lasting energy source by mining asteroids. In addition, mentors organized fun science activities, like liquid nitrogen making and shooting bottle rockets, to give students a break from coding. “Students enjoyed it and said that they learned a lot,” said Nag. “This year’s Zero Robotics game was very challenging, however, they picked up very well and the station finals had pretty awesome formation flights in microgravity!”

Since many of the students had no previous coding experience, the success of their efforts was proof of their new capabilities. Even if their SPHERE did not triumph, each student in the competition came away a winner, having learned a new skill in the area of computer programming. More importantly, as their classmates may learn this fall, they likely have a new found passion for space that could put them on the path to higher education and careers in engineering, math, science or technology.

NASA has many opportunities for teachers and students to participate in space station science and education. Zero Robotics organizes yearly robotics programming tournaments for students, including the upcoming SPHERES Zero Robotics high school competition, which kicks off nationwide this month. The final event for the high school challenge will take place in December 2011.

Although a Zero Robotics Summer SPHERES Program 2012 challenge has yet to be planned, there are hopes for growth in the program. “Zero Robotics’ high school program operates nationwide and is looking to go international,” said Nag. “Given the positive feedback from students in the summer programs, we are also very keen on expanding the middle school program nationwide, given funding and support.”

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NASA’s twin lunar Gravity Recovery and Interior Laboratory (GRAIL) spacecraft lifted off from Cape Canaveral Air Force Station in Florida at 9:08 a.m. EDT (6:08 a.m. PDT) Saturday, Sept. 10, to study the moon in unprecedented detail.

GRAIL-A is scheduled to reach the moon on New Year’s Eve 2011, while GRAIL-B will arrive New Year’s Day 2012. The two solar-powered spacecraft will fly in tandem orbits around the moon to measure its gravity field. GRAIL will answer longstanding questions about the moon and give scientists a better understanding of how Earth and other rocky planets in the solar system formed.

“If there was ever any doubt that Florida’s Space Coast would continue to be open for business, that thought was drowned out by the roar of today’s GRAIL launch,” said NASA Administrator Charles Bolden. “GRAIL and many other exciting upcoming missions make clear that NASA is taking its next big leap into deep space exploration, and the space industry continues to provide the jobs and workers needed to support this critical effort.”

The spacecraft were launched aboard a United Launch Alliance Delta II rocket. GRAIL mission controllers acquired a signal from GRAIL-A at 10:29 a.m. EDT (7:29 a.m. PDT). GRAIL-B’s signal was received eight minutes later. The telemetry downlinked from both spacecraft indicates they have deployed their solar panels and are operating as expected.

“Our GRAIL twins have Earth in their rearview mirrors and the moon in their sights,” said David Lehman, GRAIL project manager at NASA’s Jet Propulsion Laboratory in Pasadena, Calif. “The mission team is ready to test, analyze and fine-tune our spacecraft over the next three-and-a-half months on our journey to lunar orbit.”

The straight-line distance from Earth to the moon is approximately 250,000 miles (402,336 kilometers). NASA’s Apollo moon crews needed approximately three days to cover that distance. However, each spacecraft will take approximately 3.5 months and cover more than 2.5 million miles (4 million kilometers) to arrive. This low-energy trajectory results in the longer travel time. The size of the launch vehicle allows more time for spacecraft check-out and time to update plans for lunar operations. The science collection phase for GRAIL is expected to last 82 days.

“Since the earliest humans looked skyward, they have been fascinated by the moon,” said GRAIL principal investigator Maria Zuber from the Massachusetts Institute of Technology in Cambridge. “GRAIL will take lunar exploration to a new level, providing an unprecedented characterization of the moon’s interior that will advance understanding of how the moon formed and evolved.”

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The sun’s surface dances. Giant loops of magnetized solar material burst up, twist, and fall back down. Some erupt, shooting radiation flares and particles out into space. Forced to observe this dance from afar, scientists use all the tools at their disposal to look for patterns and connections to discover what causes these great explosions. Mapping these patterns could help scientists predict the onset of space weather that bursts toward Earth from the sun, interfering with communications and Global Positioning System (GPS) signals.

Analysis of 191 solar flares since May 2010 by NASA’s Solar Dynamics Observatory (SDO) has recently shown a new piece in the pattern: some 15 percent of the flares have a distinct “late phase flare” some minutes to hours later that has never before been fully observed. This late phase of the flare pumps much more energy out into space than previously realized.

“We’re starting to see all sorts of new things,” says Phil Chamberlin, deputy project scientist for SDO at NASA’s Goddard Space Flight Center in Greenbelt, Md. “We see a large increase in emissions a half-hour to several hours later, that is sometimes even larger than the original, traditional phases of the flare. In one case on November 3, 2010, measuring only the effects of the main flare would mean underestimating the amount of energy shooting into Earth’s atmosphere by 70 percent.”

The entire space weather system, from the sun’s surface to the outer edges of the solar system, is dependent on how energy transfers from one event to another – magnetic reconnection near the sun transferred to movement energy barreling across space to energy deposited into Earth’s atmosphere, for example. Better understanding of this late phase flare will help scientists quantify just how much energy is produced when the sun erupts.

The team found evidence for these late phases when SDO first began collecting data in May of 2010 and the sun decided to put on a show. In that very first week, in the midst of an otherwise fairly quiet time for the sun, there sprouted some nine flares of varying sizes. Flare sizes are divided into categories, named A, B, C, M and X, that have long been defined by the intensity of the X-rays emitted at the flare’s peak as measured by the GOES (Geostationary Operational Environmental Satellite) satellite system. GOES is a NOAA-operated network of satellites that has been in geosynchronous orbit near Earth since 1976. One of the GOES satellites measures only X-ray emissions and is a crucial source of information on space weather that the sun sends our way.

That May 2010, however, SDO observed those flares with its multi-wavelength vision. It recorded data indicating that some other wavelengths of light weren’t behaving in sync with the X-rays, but peaked at other times.

“For decades, our standard for flares has been to watch the x-rays and see when they peak,” says Tom Woods, a space scientist at the University of Colorado, Boulder, Colo. who is first author on a paper on this subject that goes online September 7 in the Astrophysical Journal. “That’s our definition for when a flare goes off. But we were seeing peaks that didn’t correspond to the X-rays.” Woods says that at first they were worried the data were an anomaly or a glitch in the instruments. But as they confirmed the data with other instruments and watched the patterns repeat over many months, they began to trust what they were seeing. “And then we got excited,” he says.

Over the course of a year, the team used the EVE (for Extreme ultraviolet Variability Experiment) instrument on SDO to record data from many more flares. EVE doesn’t snap conventional images. Woods is the principal investigator for the EVE instrument and he explains that it collects all the light from the sun at once and then precisely separates each wavelength of light and measures its intensity. This doesn’t produce pretty pictures the way other instruments on SDO do, but it provides graphs that map out how each wavelength of light gets stronger, peaks, and diminishes over time. EVE collects this data every 10 seconds, a rate guaranteed to provide brand new information about how the sun changes, given that previous instruments only measured such information every hour and a half or didn’t look at all the wavelengths simultaneously – not nearly enough information to get a complete picture of the heating and cooling of the flare.

Recording extreme ultraviolet light, the EVE spectra showed four phases in an average flare’s lifetime. The first three have been observed and are well established. (Though EVE was able to measure and quantify them over a wide range of light wavelengths better than has ever been done.) The first phase is the hard X-ray impulsive phase, in which highly energetic particles in the sun’s atmosphere rain down toward the sun’s surface after an explosive event in the atmosphere known as magnetic reconnection. They fall freely for some seconds to minutes until they hit the denser lower atmosphere, and then the second phase, the gradual phase, begins. Over the course of minutes to hours, the solar material, called plasma, is heated and explodes back up, tracing its way along giant magnetic loops, filling the loops with plasma. This process sends off so much light and radiation that it can be compared to millions of hydrogen bombs.

The third phase is characterized by the sun’s atmosphere — the corona –losing brightness, and so is known as the coronal dimming phase. This is often associated with what’s known as a coronal mass ejection, in which a great cloud of plasma erupts off the surface of the sun.

But the fourth phase, the late phase flare, spotted by EVE was new. Anywhere from one to five hours later for several of the flares, they saw a second peak of warm coronal material that didn’t correspond to another X-ray burst.

“Many observations have spotted an increased extreme ultraviolet peak just seconds to minutes after the main phase of the flare, and this behavior is considered a normal part of the flare process. But this late phase is different,” says Goddard’s Chamberlin, who is also a co-author on the paper. “These emissions happen substantially later. And it happens after the main flare exhibits that initial peak.”

To try to understand what was happening, the team looked at the images collected from SDO’s Advanced Imaging Assembly (AIA) as well. They could see the main phase flare eruption in the images and also noticed a second set of coronal loops far above the original flare site. These extra loops were longer and become brighter later than the original set (or the post-flare loops that appeared just minutes after that). These loops were also physically set apart from those earlier ones.

“The intensity we’re recording in those late phase flares is usually dimmer than the X-ray intensity,” says Woods. “But the late phase goes on much longer, sometimes for multiple hours, so it’s putting out just as much total energy as the main flare that typically only lasts for a few minutes.” Because this previously unrealized extra source of energy from the flare is equally important to impacting Earth’s atmosphere, Woods and his colleagues are now studying how the late phase flares can influence space weather.

The late phase flare is, of course, just one piece of the puzzle as we try to understand the star with which we live. But keeping track of the energy, measuring all the different wavelengths of light, using all the instruments NASA has at its disposal, such information helps us map out all the steps of the sun’s great dance.

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