Thursday, August 29, 2013

NASA Solar Dynamics Observatory (SDO): Untangling motion inside the Sun

Observations by the Helioseismic and Magnetic Imager on NASA's Solar Dynamics Observatory show a two-level system of circulation inside the sun. 

Such circulation is connected to the flip of the sun's north and south magnetic poles that occurs approximately every 11 years. 

Credit: Stanford University

Using an instrument on NASA's Solar Dynamics Observatory, called the Helioseismic and Magnetic Imager (HMI), scientists have overturned previous notions of how the sun's writhing insides move from equator to pole and back again, a key part of understanding how the dynamo works.

Modeling this system also lies at the heart of improving predictions of the intensity of the next solar cycle.

Using SDO, scientists see a performance of explosions and fountains on the solar surface. Shots of solar material leap into the air.

Dark blemishes called sunspots grow, combine and disappear as they travel across the sun's face. Bright loops of charged particles – captured by magnetic fields dancing around the sun – hover in the atmosphere.

This dynamic display is all powered by a complex, ever-changing magnetic current inside the sun known as the dynamo.

This magnetic system flips approximately every 11 years, with magnetic north and magnetic south switching poles.

This process is an integral part of the sun's progression toward a pinnacle of solar activity, known as solar maximum.

The team's recent results show that, instead of a simple cycle of flow moving toward the poles near the sun's surface and then back to the equator, the material inside the sun shows a double layer of circulation, with two such cycles on top of each other.

The results appear online in the Astrophysical Journal Letters on Aug. 27, 2013.

"For decades people have known that the solar cycle depends on the poleward flow or material, changing the magnetic fields from one cycle to the next," said Philip Scherrer, principal investigator for HMI at Stanford University in Stanford, Calif.

"We mapped out what we believed to be the flow pattern in the 1990s, but the results didn't quite make sense."

Since the mid-1990s researchers have been observing movement inside the sun using a technique called helioseismology.

The technique makes use of the fact that waves course across the sun, back and forth, oscillating with an approximately five minute period.

Such waves are similar to the seismic waves that spread out under the ground during an earthquake. By monitoring the oscillations seen at the surface of the sun, scientists can gather information about the material through which the waves traveled, including what the material is made of and how fast and in what direction it is moving.

More information:

NASA Cassini: Data from Titan indicate a rigid, weathered ice shell

A rigid ice shell resists the upward pressure of a buoyant root, whose low density produces a negative gravity anomaly. 

Upward deflection of the ice shell creates positive topography, but surface weathering keeps that topography small. 

Credit: Doug Hemingway

An analysis of gravity and topography data from Saturn's largest moon, Titan, has revealed unexpected features of the moon's outer ice shell.

The best explanation for the findings, the authors said, is that Titan's ice shell is rigid and that relatively small topographic features on the surface are associated with large roots extending into the underlying ocean.

The study is published in the August 29 issue of the journal Nature.

Led by planetary scientists Douglas Hemingway and Francis Nimmo at the University of California, Santa Cruz, the study used new data from NASA's Cassini spacecraft.

The researchers were surprised to find a negative correlation between the gravity and topography signals on Titan.

"Normally, if you fly over a mountain, you expect to see an increase in gravity due to the extra mass of the mountain. On Titan, when you fly over a mountain the gravity gets lower. That's a very odd observation," said Nimmo, a professor of Earth and planetary sciences at UC Santa Cruz.

To explain that observation, the researchers developed a model in which each bump in the topography on the surface of Titan is offset by a deeper "root" big enough to overwhelm the gravitational effect of the bump on the surface.

The root is like an iceberg extending below the ice shell into the ocean underneath it. "Because ice is lower density than water, you get less gravity when you have a big chunk of ice there than when you have water," Nimmo explained.

An iceberg floating in water is in equilibrium, its buoyancy balancing out its weight. In this model of Titan, however, the roots extending below the ice sheet are so much bigger than the bumps on the surface that their buoyancy is pushing them up against the ice sheet.

"It's like a big beach ball under the ice sheet pushing up on it, and the only way to keep it submerged is if the ice sheet is strong," said Hemingway, a doctoral candidate in planetary geophysics at UCSC and lead author of the paper.

"If large roots are the reason for the negative correlation, it means that Titan's ice shell must have a very thick rigid layer."

The researchers calculated that, in this model, Titan's ice shell would have to have a rigid layer at least 40 kilometers thick.

They also found that hundreds of meters of surface erosion and deposition are needed to account for the observed imbalance between the large roots and small surface topography.

The results from their model are similar to estimates obtained by geo-morphologists studying the erosion of impact craters and other features on Titan.

These findings have several implications. For example, a thick rigid ice shell makes it very difficult to produce ice volcanoes, which some have proposed to explain certain features seen on the surface.

More information: Nature paper:

Solar System: Life began on Mars - Boron and Molybdenum

New evidence has emerged which supports the long-debated theory that life on Earth may have started on Mars.

Professor Steven Benner will tell geochemists gathering today (Thursday 29 Aug) at the annual Goldschmidt conference that an oxidized mineral form of the element molybdenum, which may have been crucial to the origin of life, could only have been available on the surface of Mars and not on Earth.

"In addition", said Professor Benner "recent studies show that these conditions, suitable for the origin of life, may still exist on Mars."

"It's only when molybdenum becomes highly oxidized that it is able to influence how early life formed," explains Professor Benner, from The Westheimer Institute for Science and Technology in the USA.

"This form of molybdenum couldn't have been available on Earth at the time life first began, because three billion years ago the surface of the Earth had very little oxygen, but Mars did. It's yet another piece of evidence which makes it more likely life came to Earth on a Martian meteorite, rather than starting on this planet."

The research Professor Benner will present at the Goldschmidt conference tackles two of the paradoxes which make it difficult for scientists to understand how life could have started on Earth.

The first is dubbed by Professor Benner as the 'tar paradox'. All living things are made of organic matter, but if you add energy such as heat or light to organic molecules and leave them to themselves, they don't create life. Instead, they turn into something more like tar, oil or asphalt.

"Certain elements seem able to control the propensity of organic materials to turn into tar, particularly boron and molybdenum, so we believe that minerals containing both were fundamental to life first starting," says Professor Benner.

"Analysis of a Martian meteorite recently showed that there was boron on Mars; we now believe that the oxidized form of molybdenum was there too."

The second paradox is that life would have struggled to start on the early Earth because it was likely to have been totally covered by water.

Not only would this have prevented sufficient concentrations of boron forming – it's currently only found in very dry places like Death Valley – but water is corrosive to RNA, which scientists believe was the first genetic molecule to appear.

Although there was water on Mars, it covered much smaller areas than on early Earth.

"The evidence seems to be building that we are actually all Martians; that life started on Mars and came to Earth on a rock," says Professor Benner.

"It's lucky that we ended up here nevertheless, as certainly Earth has been the better of the two planets for sustaining life. If our hypothetical Martian ancestors had remained on Mars, there might not have been a story to tell."

More information:

Wednesday, August 28, 2013

ULA Delta 4: US Largest Rocket Launches Top-Secret Spy Satellite

A United Launch Alliance (ULA) Delta 4 Heavy rocket carrying a payload for the National Reconnaissance Office (NRO) lifted off from Space Launch Complex-6 here at 11:03 a.m. PDT today. 

Designated NROL-65, the mission is in support of national defense. This is ULA’s eighth launch in 2013, the 24th Delta 4 mission and the second Delta 4 Heavy launch from Vandenberg Air Force Base.

Credit: Pat Corkery/United Launch Alliance

The United States' largest rocket launched a spy satellite on a hush-hush mission Wednesday (Aug. 28).

An unmanned Delta 4-Heavy rocket lifted off the pad at California's Vandenberg Air Force Base at 2:03 p.m. EDT (1803 GMT) Wednesday, carrying a classified payload to a polar orbit for the U.S. National Reconnaissance Office (NRO).

"Today's launch is dedicated to the men and women who serve for our nation's freedom," a commentator said a few minutes into the liftoff.

It's unclear what intelligence the spacecraft, which is known as NROL-65, will collect as it zips around our planet. Because of the clandestine nature of the mission, it entered a planned media blackout about seven minutes after liftoff.

"We are truly honored to deliver this critical asset to orbit," said Jim Sponnick, United Launch Alliance vice president for the Atlas and Delta Programs. "The ULA Delta 4 Heavy is currently the world's largest rocket, providing the nation with reliable, proven, heavy lift capability for our country’s national security payloads from both the east and west coasts."

The Delta 4 Heavy, which is built by ULA and first flew in 2004, is the biggest and most powerful American rocket in operation today. The 235-foot-tall (72 meters) launcher generates about 2 million pounds of thrust at liftoff, according to ULA officials.

ESA VLT: Oldest solar twin identified

This image tracks the life of a Sun-like star, from its birth on the left side of the frame to its evolution into a red giant star on the right. 

On the left the star is seen as a protostar, embedded within a dusty disc of material as it forms. It later becomes a star like our Sun. 

After spending the majority of its life in this stage, the star's core begins to gradually heat up, the star expands and becomes redder until it transforms into a red giant. 

Following this stage, the star will push its outer layers into the surrounding space to form an object known as a planetary nebula, while the core of the star itself will cool into a small, dense remnant called a white dwarf star. 

Marked on the lower timeline are where our Sun and solar twins 18 Sco and HIP 102152 are in this life cycle. 

The Sun is 4.6 billion years old and 18 Sco is 2.9 billion years old, while the oldest solar twin is some 8.2 billion years old -- the oldest solar twin ever identified. 

By studying HIP 102152, we can get a glimpse of what the future holds for our Sun. 

This image is illustrative; the ages, sizes, and colours are approximate (not to scale). The protostar stage, on the far left of this image, can be some 2000 times larger than our Sun. 

The red giant stage, on the far right of this image, can be some 100 times larger than the Sun. 

Credit: ESO/M. Kornmesser

An international team led by astronomers in Brazil has used ESO's Very Large Telescope to identify and study the oldest solar twin known to date.

Located 250 light-years from Earth, the star HIP 102152 is more like the Sun than any other solar twin—except that it is nearly four billion years older.

This older, but almost identical, twin gives us an unprecedented chance to see how the Sun will look when it ages.

The new observations also provide an important first clear link between a star's age and its lithium content, and in addition suggest that HIP 102152 may be host to rocky terrestrial planets.

Astronomers have only been observing the Sun with telescopes for 400 years—a tiny fraction of the Sun's age of 4.6 billion years.

It is very hard to study the history and future evolution of our star, but we can do this by hunting for rare stars that are almost exactly like our own, but at different stages of their lives.

Now astronomers have identified a star that is essentially an identical twin to our Sun, but 4 billion years older—almost like seeing a real version of the twin paradox in action.

Jorge Melendez (Universidade de São Paulo, Brazil), the leader of the team and co-author of the new paper explains: "For decades, astronomers have been searching for solar twins in order to know our own life-giving Sun better.

But very few have been found since the first one was discovered in 1997. We have now obtained superb-quality spectra from the VLT and can scrutinise solar twins with extreme precision, to answer the question of whether the Sun is special."

The team studied two solar twins—one that was thought to be younger than the Sun (18 Scorpii) and one that was expected to be older (HIP 102152).

They used the UVES spectrograph on the Very Large Telescope (VLT) at ESO's Paranal Observatory to split up the light into its component colours so that the chemical composition and other properties of these stars could be studied in great detail.

They found that HIP 102152 in the constellation of Capricornus (The Sea Goat) is the oldest solar twin known to date.

It is estimated to be 8.2 billion years old, compared to 4.6 billion years for our own Sun. On the other hand 18 Scorpii was confirmed to be younger than the Sun—about 2.9 billion years old.

More information: This research was presented in a paper to appear in "High precision abundances of the old solar twin HIP 102152: insights on Li depletion from the oldest Sun", by TalaWanda Monroe et al. in the Astrophysical Journal Letters. Research paper PDF

NASA's Mars Curiosity MSL debuts autonomous navigation

This mosaic of images from the Navigation Camera (Navcam) on NASA's Mars rover Curiosity shows the scene from the rover's position on the 376th Martian day, or sol, of the mission (Aug. 27, 2013). (Click on the image to see bigger version)

The images were taken right after Curiosity completed the first drive during which it used autonomous navigation on unknown ground. 

Credit: NASA/JPL-Caltech

NASA's Mars rover Curiosity has used autonomous navigation for the first time, a capability that lets the rover decide for itself how to drive safely on Mars.

This latest addition to Curiosity's array of capabilities will help the rover cover the remaining ground en route to Mount Sharp, where geological layers hold information about environmental changes on ancient Mars.

The capability uses software that engineers adapted to this larger and more complex vehicle from a similar capability used by NASA's Mars Exploration Rover Opportunity, which is also currently active on Mars.

Using autonomous navigation, or autonav, Curiosity can analyze images it takes during a drive to calculate a safe driving path. This enables it to proceed safely even beyond the area that the human rover drivers on Earth can evaluate ahead of time.

On Tuesday, Aug. 27, Curiosity successfully used autonomous navigation to drive onto ground that could not be confirmed safe before the start of the drive.

This was a first for Curiosity. In a preparatory test last week, Curiosity plotted part of a drive for itself, but kept within an area that operators had identified in advance as safe.

"Curiosity takes several sets of stereo pairs of images, and the rover's computer processes that information to map any geometric hazard or rough terrain," said Mark Maimone, rover mobility engineer and rover driver at NASA's Jet Propulsion Laboratory, Pasadena, Calif.

"The rover considers all the paths it could take to get to the designated endpoint for the drive and chooses the best one."

The drive on Tuesday, the mission's 376th Martian day, or "sol," took Curiosity across a depression where ground-surface details had not been visible from the location where the previous drive ended.

The drive included about 33 feet (10 meters) of autonomous navigation across hidden ground as part of a day's total drive of about 141 feet (43 meters).

"We could see the area before the dip, and we told the rover where to drive on that part. We could see the ground on the other side, where we designated a point for the rover to end the drive, but Curiosity figured out for herself how to drive the uncharted part in between," said JPL's John Wright, a rover driver.

NASA's Mars rover Curiosity left the "Glenelg" area on July 4, 2013, on a "rapid transit route" to the entry point for the mission's next major destination, the lower layers of Mount Sharp. 

As of Aug. 27, 2013, NASA's Mars rover Curiosity has driven about 0.86 mile (1.39 kilometers) since leaving Glenelg, with about 4.46 miles (7.18 kilometers) remaining to get to the entry point. 

The rover's drive on Aug. 27, the 376th sol (Martian day) of the mission, was the first Curiosity drive using the rover's autonomous navigation capability to safely drive beyond the area that rover drivers on Earth could evaluate from images before the drive. 

The rover can analyze stereo images that it takes during the drive and choose the best path to continue driving. 

Credit: NASA/JPL-Caltech/Univ. of Arizona

Curiosity is nearly two months into a multi-month trek from the "Glenelg" area, where it worked for the first half of 2013, to an entry point for the mission's major destination: the lower layers of a 3-mile-tall (5-kilometer-tall) mound called Mount Sharp.

The latest drive brought the distance traveled since leaving Glenelg to 0.86 mile (1.39 kilometers). The remaining distance to the Mount Sharp entry point is about 4.46 miles (7.18 kilometers) along a "rapid transit route."

That route was plotted on the basis of images from the High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter.

The actual driving route, which will be based on images from Curiosity's own cameras, could be longer or shorter.

Curiosity's science team has picked a few waypoints along the rapid transit route to Mount Sharp where driving may be suspended for a few days for science.

The rover has about 0.31 mile (500 meters) left to go before reaching the first of these waypoints, which appears from orbiter images to offer exposed bedrock for inspection.

"Each waypoint represents an opportunity for Curiosity to pause during its long journey to Mount Sharp and study features of local interest," said Curiosity Project Scientist John Grotzinger of the California Institute of Technology, Pasadena.

"These features are geologically interesting, based on HiRISE images, and they lie very close to the path that provides the most expeditious route to the base of Mount Sharp.

We'll study each for several sols, perhaps selecting one for drilling if it looks sufficiently interesting."

After landing inside Gale Crater in August 2012, Curiosity drove eastward to the Glenelg area, where it accomplished the mission's major science objective of finding evidence for an ancient wet environment that had conditions favorable for microbial life.

The rover's route is now southwestward. At Mount Sharp, in the middle of Gale Crater, scientists anticipate finding evidence about how the ancient Martian environment changed and evolved.

Micro Ion Thrusters: The newest little idea for nanosat micro rockets

L. Brad King's prototype of a ferrofluid ion thruster. When subjected to voltage, the points of the crown arise from a ring-shaped trench circling a one-inch block of aluminum. 

Credit: L. Brad King

Nanosatellites are smartphone-sized gadgets that can perform simple, yet valuable, space missions.

Dozens of these little spacecraft are now tirelessly orbiting the earth performing valuable missions for NASA, the Department of Defense and even private companies.

Nano-satellites borrow many of their components from terrestrial gadgets: miniaturized cameras, wireless radios and GPS receivers that have been perfected for hand-held devices are also perfect for spacecraft.

However, according to Michigan Technological University's Lyon Brad King, there is at least one technology need that is unique to space: "Even the best smartphones don't have miniaturized rocket engines, so we need to develop them from scratch."

Miniature rockets aren't needed to launch a nano-satellite from Earth. The small vehicles can hitchhike with a regular rocket that is going that way anyway.

But because they are hitchhikers, these nano-satellites don't always get dropped off in their preferred location.

Once in space, a nano-satellite might need some type of propulsion to move it from its drop-off point into its desired orbit. This is where the micro rocket engine comes in.

For the last few years, researchers around the world have been trying to build such rockets using microscopic hollow needles to electrically spray thin jets of fluid, which push the spacecraft in the opposite direction.

The fluid propellant is a special chemical known as an ionic liquid. A single thruster needle is finer than a human hair, less than one millimeter long and produces a thrust force equivalent to the weight of a few grains of sand.

A few hundred of these needles fit in a postage-stamp-size package and produce enough thrust to maneuver a nano-satellite.

Lyon Brad King
These new electrospray thrusters face some design challenges, however. "Because they are so small and intricate, they are expensive to make, and the needles are fragile," says King, the 'Ron and Elaine Starr' Professor of Mechanical Engineering-Engineering Mechanics.

"They are easily destroyed either by a careless bump or an electrical arc when they're running."

To get around the problem, King and his team have developed an elegant strategy: eliminate the expensive and tedious micro-fabrication required to make the needles by letting Mother Nature take care of the assembly.

"We're working with a unique type of liquid called a ferro-fluid that naturally forms a stationary pattern of sharp tips in the liquid surface," he says.

"Each tip in this self-assembling structure can spray a jet of fluid just like a micro-needle, so we don't actually have to make any needles."

Ferro-fluids have been around since the 1960s. They are made of tiny magnetic particles suspended in a solvent that moves when magnetic force is applied.

King illustrates with a tiny container holding a ferro-fluid made of kerosene and iron dust. The fluid lies flat until he puts a magnet beneath it.

Then suddenly, the liquid forms a regular series of peaks reminiscent of a mountain range.

These peaks remain perfectly stable despite vigorous shaking and even turning the container upside down. It is, nonetheless, completely liquid, as a finger-tip touch proves undeniably.

When the magnet is removed, the liquid relaxes to a perfectly flat surface.

King's team was trying to make an ionic liquid that behaved like a ferro-fluid when they learned about a research team at the University of Sydney that was already making these substances.

The Sydney team was using magnetic nanoparticles made by the life-sciences company Sirtex, which are used to treat liver cancer. "They sent us a sample, and we've used it to develop a thruster," King said.

"Now we have a nice collaboration going. It's amazing that the same technology used to treat cancer can also function as a micro rocket for spacecraft."

King's first thruster is made of a one-inch block of aluminum containing a small ring of the special fluid. When a magnet is placed beneath the block, the liquid forms a tiny, five-tipped crown.

Their thruster isn't ready to push a satellite around in orbit just yet. "First we have to really understand what is happening on a microscopic level, and then develop a larger prototype based on what we learn," King said.

"We're not quite there yet; we can't build a person out of liquid, like the notorious villain from the Terminator movies. But we're pretty sure we can build a rocket engine."

Tuesday, August 27, 2013

NASA's Spitzer Image Carina Nebula: Brighter Than a Thousand Thousand Suns

This new view shows the Carina nebula as seen in a new image made by NASA's Spitzer Space Telescope. 

At the center of the nebula lies Eta Carinae, one of the most massive stars in the galaxy. 

Its blinding glare sculpts and destroys the surrounding nebula.

Eta Carinae represents a true giant of a star. 

It contains 100 times the mass of our sun, and burns its nuclear fuel so quickly that it blazes at least one million times brighter than the sun. 

It has brightened and faded over the years, and some astronomers think it could explode as a supernova in the not-too-distant future.

ISS NASA Spacesuit Leak: Problem recreated - Video

ISS astronauts Luca Parmitano and Chris Cassidy tested the suit aboard the International Space Station and found that the helmet continues to leak water. The cause is still under investigation.

Credit: NASA

NASA to Crash Test Helicopter to Study Safety

Anybody who says NASA researchers don't know how to have a smashing good time has not met a team at NASA's Langley Research Center in Hampton, Va.

They are test engineers whose job it is to make aircraft safer by crashing them.

In late August those engineers plan to drop a 45-foot long helicopter fuselage from about 30 feet to test improved seat belts and seats and to collect crash-worthiness data.

NASA is collaborating with the Navy, Army and Federal Aviation Administration on the Transport Rotorcraft Airframe Crash Testbed full-scale crash tests at NASA Langley's Landing and Impact Research (LandIR) Facility.

LandIR, a 240-foot high, 400-foot long gantry, has an almost 50-year history.

It started out as the Lunar Landing Research Facility, where Neil Armstrong and other astronauts learned to land on the moon.

Then it became a crash test facility where engineers could simulate aircraft accidents.

And recently it added a big pool where NASA is testing Orion space capsule mock-ups in anticipation of water landings.

The August drop test is one of the most complicated and ambitious aircraft crash experiments at NASA Langley in recent memory.

"We have instrumented a former Marine helicopter airframe with cameras and accelerometers," said lead test engineer Martin Annett.

"Almost 40 cameras inside and outside of the helicopter will record how 13 crash test dummies react before, during and after impact. Onboard computers will also record more than 350 channels of data."

External cameras will capture images of an unusual looking helicopter. Instead of the usual Marine gray, technicians painted one entire side in black polka dots over a white background.

It is not a fashion statement, but a photographic technique called full field photogrammetry. Each dot represents a data point.

High speed cameras filming at 500 images per second track each dot, so after everything is over, researchers can plot and "see" exactly how the fuselage buckled, bent, cracked or collapsed under crash loads.

NASA Langley is planning to stream the crash test August 28 on the Internet live at about 1 p.m. EDT at:

LADEE, Lunar Atmosphere and Dust Environment Explorer

In an attempt to answer prevailing questions about our moon, NASA is making final preparations to launch a probe at 11:27 p.m. EDT Friday, Sept. 6, 2013, from NASA's Wallops Flight Facility on Wallops Island, Va.

The small car-sized Lunar Atmosphere and Dust Environment Explorer (LADEE) is a robotic mission that will orbit the moon to gather detailed information about the structure and composition of the thin lunar atmosphere and determine whether dust is being lofted into the lunar sky. 

A thorough understanding of these characteristics of our nearest celestial neighbor will help researchers understand other bodies in the solar system, such as large asteroids, Mercury, and the moons of outer planets.

In this photo, engineers as NASA's Wallops Flight Facility in Virginia encapsule the LADEE spacecraft into the fairing of the Minotaur V launch vehicle nose-cone. 

LADEE is the first spacecraft designed, developed, built, integrated and tested at NASA's Ames Research Center in Moffett Field, Calif. 

Image credit: NASA Wallops / Terry Zaperach

Remote detection of magmatic water in Bullialdus Crater on the Moon

Mosaic of the near side of the moon as taken by the Clementine star trackers. The images were taken on March 15, 1994. 

Credit: NASA

A research team with members from Johns Hopkins University Applied Physics Laboratory and the US Geological Survey has concluded that hydroxyl molecules found in the central peak of a crater on the moon indicates that the moon likely had a water component when it was first formed.

In their paper published in the journal Nature Geoscience, the researchers suggest that because the rock in which it was found likely came from deep within the moon, it's not likely the hydroxyl was formed by solar wind flux or by other bodies striking its surface.

Bullialdus Crater is on the near side of the moon, situated near the rim of the much larger impact basin.

At the center of the crater is rocky material that was pulled to the surface as the result of an impact, forming a peak.

The team looked at data from M3 and Lunar Reconnaissance Orbiter (LRO) Cameras available from NASA's planetary data system, which allowed them (via spectroscopic readings) to detect the presence of hydroxyl molecules—which is considered to be a sub-structure of water molecules.

This is not the first time hydroxyl has been seen on the lunar surface, of course, but other instances have been attributed to deposits created by interactions between solar wind flux and minerals on the surface or from other bodies that collided with the moon.

Prior research has shown that when hydroxyl is created or deposited on the moon, it generally sticks to cooler parts of the surface and moves as the temperature changes—the hydroxyl molecules found in the craters central peak.

However, indicating they are embedded, which the researchers interpret to mean that they were part of the rock that was pushed up from below when the crater was formed.

They also noted that there was no evidence of hydroxyl anywhere else near the crater.

The researchers theorize that the impact that created the larger impact zone likely caused material to be pulled from deep within the moon and deposited nearby.

The subsequent impact that caused the creation of the much smaller Bullialdus Crater, then caused material that had been spewed by the larger impact to be pulled to the surface of its central peak and that material, the team concludes, likely included water.

More information: Remote detection of magmatic water in Bullialdus Crater on the Moon, Nature Geoscience (2013) DOI: 10.1038/ngeo1909

Once considered dry compared with Earth, laboratory analyses of igneous components of lunar samples have suggested that the Moon's interior is not entirely anhydrous. 

Water and hydroxyl have also been detected from orbit on the lunar surface, but these have been attributed to nonindigenous sources, such as interactions with the solar wind. 

Magmatic lunar volatiles—evidence for water indigenous to the lunar interior—have not previously been detected remotely. 

Here we analyse spectroscopic data from the Moon Mineralogy Mapper (M3) and report that the central peak of Bullialdus Crater is significantly enhanced in hydroxyl relative to its surroundings. 

We suggest that the strong and localized hydroxyl absorption features are inconsistent with a surficial origin. 

Instead, they are consistent with hydroxyl bound to magmatic minerals that were excavated from depth by the impact that formed Bullialdus Crater. 

Furthermore, estimates of thorium concentration in the central peak using data from the Lunar Prospector orbiter indicate an enhancement in incompatible elements, in contrast to the compositions of water-bearing lunar samples2. 

We suggest that the hydroxyl-bearing material was excavated from a magmatic source that is distinct from that of samples analysed thus far.

Monday, August 26, 2013

CSIRO telescope marks 25 years of success

CSIRO's Australia Telescope Compact Array. Credit: David Smyth

One of the world's most successful astronomy observatories, CSIRO's Australia Telescope Compact Array near Narrabri, New South Wales (NSW), turns 25 years of age on 2 September.

CSIRO will celebrate with a public Open Day at the telescope site on 1 September, then a formal ceremony and a scientific meeting.

The Compact Array is a set of six dishes that work together as one much larger radio telescope. It lies between the towns of Narrabri and Wee Waa in northwest NSW, about 500 km from Sydney, at CSIRO's Paul Wild Observatory.

Black holes, exploding stars, magnetic fields in space, galaxies at the edge of the observable universe: the Compact Array studies them all.

The universe is a huge natural laboratory and astronomers study it to observe nature at its most extreme.

Jamie Stevens
"Every possible experiment is being played out somewhere in the universe," said Dr. Jamie Stevens, CSIRO's Senior Systems Scientist for the Compact Array.

The Compact Array has given us the first 3D picture of the radiation belts around Jupiter, the first good evidence linking exploding stars with flashes of gamma rays, and the first image showing how gas churns in interstellar space.

The telescope is so sensitive that it would see a mobile phone on the Moon as a very strong radio source. It can be pointed with an accuracy of better than two arcseconds—about the width of a finger seen one kilometer away.

The Compact Array is to astronomy what the Australian swimming team is to sport: a world-class achiever for many years.

It is among the top three telescopes of its kind by both publication numbers and citations. After the race, it would be standing on the podium!

About 500 scientists from around the world use the telescope each year.

The telescope has become better and better over time, as upgrades have made it more sensitive to faint radio signals and allowed it to capture more of the radio spectrum.

In 2012 Compact Array data led to 76 refereed science papers—more than in any previous year of the telescope's history.

"I never tire of observing with the Compact Array," Dr. Stevens said. "It's a factory for discovery."

The telescope was funded as a project for Australia's Bicentennial in 1988, and was opened by the then Prime Minister, Bob Hawke.

It boosted Australia's international standing in radio astronomy, enabling CSIRO to develop the Australian SKA Pathfinder in Western Australia and Australia to win the right to co-host the international Square Kilometre Array telescope.

Major volcanic eruption seen on Jupiter's moon Io

Voyager 1 acquired this image of Io on March 4, 1979. An enormous volcanic explosion can be seen silhouetted against dark space over Io’s bright limb. 

Credit: NASA/JPL

Recent observations of Jupiter's moon Io has revealed a massive volcanic eruption taking place 628,300,000 km (390,400,000 miles) from Earth. Io, the innermost of the four largest moons around Jupiter, is the most volcanically active object in the Solar System with about 240 active regions.

But this new one definitely caught the eye of Dr. Imke de Pater, Professor of Astronomy and of Earth and Planetary Science at the University of California in Berkeley.

She was using the Keck II telescope on Mauna Kea in Hawaii on August 15, 2013 when it immediately became apparent something big was happening at Io.

"When you are right at the telescope and see the data, this is something you can see immediately, especially with a big eruption like that," de Pater told reporters.

de Pater said this eruption is one of the top 10 most powerful eruptions that have been seen on this moon.

"It is a very energetic eruption that covers over a 30 square kilometer area," she said.

"For Earth, that is big, and for Io it is very big too. It really is one of the biggest eruptions we have seen."

She added the new volcano appears to have a large energy output. "We saw a big eruption in 2001, which was in the Surt region, which is well known as the biggest one anyone has ever seen," she said.

"For this one, the total energy is less but per square meter, it is bigger than the one in 2001, so it is very powerful."

While Io's eruptions can't be seen directly from Earth,infrared cameras on the Keck telescope (looking between 1 and 5 microns) have been able to ascertain there are likely fountains of lava gushing from fissures in the Rarog Patera region of Io, aptly named for a Czech fire deity.

While many regions of Io are volcanically active, de Pater said she's not been able to find any other previous activity that has been reported in the Rarog Patera area, which the team finds very interesting.

Ashley Davies of NASA's Jet Propulsion Laboratory in Pasadena, California and a member of the observing team told reporters that Rarog Patera was identified as a small, relatively innocuous hot spot previously in Galileo PPR data and possibly from Earth, but at a level way, way below what was seen on August 15, and reported in New Scientist.

de Pater and other astronomers will be taking more data soon with Keck and perhaps more telescopes to try and find out more about this massive eruption.

"We never know about eruptions – they can last hours, days months or years, so we have no idea how long it will stay active," she said, "but we are very excited about it."

No data or imagery has been released on the new eruption yet since the team is still making their observations and will be writing a paper on this topic.

Scientists think a gravitational tug-of-war with Jupiter is one cause of Io's intense vulcanism.

ESA Herschel Image: Embracing Orion

Orion A. Credit: ESA/Herschel/ Ph. André, V. Könyves, N. Schneider (CEA Saclay, France) for the Gould Belt survey Key Programme

This new view of the Orion A star-formation cloud from ESA's Herschel space observatory shows the turbulent region of space that hugs the famous Orion Nebula.

The nebula lies about 1500 light years from Earth within the 'sword of Orion' – below the three main stars that form the belt of the Orion constellation.

In this view, the nebula corresponds to the brightest region in the centre of the image, where it is lit up by the Trapezium group of stars at its heart.

The scene is awash with turbulent star formation, the fierce ultraviolet radiation of massive new born stars blasting away their surrounding cloudy cocoons, carving ethereal shapes into the gas and dust.

Wispy tendrils rise like flames away from some of the most intense regions of star formation, while pillars of denser material withstand the searing blaze for longer.

Great arms of gas and dust extend from the Orion Nebula to form a ring, while a spine of cooler material weaves up through the scene to a halo of cloudy star-formation material above.

Embedded within the red and yellow filaments are a handful of point-like sources: these are protostars, the seeds of new stars that will soon ignite and begin to flood their surrounds with intense radiation.

The black regions to the top of the image and to the bottom right may seem like voids, but actually contain hints of much fainter emission that has not been emphasised in this image.

The red 'islands' of emission in the bottom right are also a subtle trick of image processing for they are connected to the main cloud by much fainter emission.

The bright 'eyes' in the two most distinct clouds indicates that the tip of each pillar has already collapsed and is forming stars.

Saturday, August 24, 2013

NASA James Webb Space Telescope: backplane arrives at Marshall Centre for testing

The James Webb Space Telescope's backplane element arrives at the Marshall Center. 

Credit: NASA/MSFC/Fred Deaton

A major piece of the James Webb Space Telescope, the mirror's primary backplane support, arrived Aug. 22 at NASA's Marshall Space Flight Center in Huntsville, Ala., for testing in the X-ray and Cryogenic Test Facility.

The backplane is the backbone of the telescope, supporting its 18 beryllium mirrors, instruments and other elements while the telescope is looking into deep space.

The Webb Telescope is the world's next-generation space observatory and successor to the Hubble Space Telescope.

To prepare the telescope for the extreme temperatures of space, engineers at the facility have carefully examined the telescope's mirrors inside a vacuum chamber that simulates the hypercold of space, chilling the hardware from room temperature down to a frigid minus 414 degrees Fahrenheit.

The backplane is the latest and final piece of the telescope to undergo this extreme conditioning at the Marshall Center.

The X-ray and Cryogenic Facility at the Marshall Center (PDF) is the world's largest X-ray telescope test facility and offers a unique, cryogenic, clean-room optical test environment.

Cryogenic testing will take place in a 7,600-cubic-foot, helium-cooled vacuum chamber, chilling the Webb support structure from room temperature to simulate the frigid atmosphere of space.

While the structure changes temperature, test engineers will precisely measure its structural stability to ensure it will perform as designed in the extreme temperatures of space.

The cryogenic testing is targeted to begin in September.

"This testing of the backplane will verify limited movement of the structure when exposed to cryogenic temperatures," said Helen Cole, project manager for Webb Telescope mirror activities at the test facility.

"This is important to overall performance of the telescope."

Crews unload the James Webb Space Telescope's "backplane," which was flown aboard a Lockheed C-5 airplane to NASA’s Marshall Space Flight Center in Huntsville, Ala. 

Credit: NASA/MSFC/Fred Deaton

"Ensuring the best performance for the telescope requires evaluating the hardware at temperatures just as cold as in the environs of space," said Jeff Kegley, the test facility's manager.

 "This is the last in a series of Webb Telescope tests our facility has been performing since 2008; it's great to have the hardware here."

A joint project of NASA, the European Space Agency and the Canadian Space Agency, the Webb Telescope will observe the most distant objects in the universe, provide images of the first galaxies formed and see unexplored planets around distant stars.

ATK built the backplane structure at its facility in Magna, Utah, under a contract with prime contractor Northrop Grumman.

NASA Spitzer telescope celebrates ten years in space

A montage of images taken by NASA's Spitzer Space Telescope over the years. Credit: NASA/JPL-Caltech

Ten years after a Delta II rocket launched NASA's Spitzer Space Telescope, lighting up the night sky over Cape Canaveral, Fla., the fourth of the agency's four Great Observatories continues to illuminate the dark side of the cosmos with its infrared eyes.

The telescope studied comets and asteroids, counted stars, scrutinized planets and galaxies, and discovered soccer-ball-shaped carbon spheres in space called buckyballs.

Moving into its second decade of scientific scouting from an Earth-trailing orbit, Spitzer continues to explore the cosmos near and far.

One additional task is helping NASA observe potential candidates for a developing mission to capture, redirect and explore a near-Earth asteroid.

"President Obama's goal of visiting an asteroid by 2025 combines NASA's diverse talents in a unified endeavor," said John Grunsfeld, NASA's associate administrator for science in Washington.

"Using Spitzer to help us characterize asteroids and potential targets for an asteroid mission advances both science and exploration."

Spitzer's infrared vision lets it see the far, cold and dusty side of the universe.

Close to home, the telescope has studied the comet dubbed Tempel 1, which was hit by NASA's Deep Impact mission in 2005.

Spitzer showed the composition of Tempel 1 resembled that of solar systems beyond our own. Spitzer also surprised the world by discovering the largest of Saturn's many rings.

The enormous ring, a wispy band of ice and dust particles, is very faint in visible light, but Spitzer's infrared detectors were able to pick up the glow from its heat.

Astronaut Sees 'UFO' Near Space Station - Video

When any kind of unidentified flying object floats by the International Space Station, you can bet astronauts are going to notice. That's just what happened this week, and one space traveler caught it all on video.

NASA astronaut Chris Cassidy was quick on the draw when he captured a video of the 'unidentified object' near the space station. He spotted the object floating near the space station on Monday (Aug. 19).

"Was it a UFO? Not really," NASA officials wrote in a video description. "Russian ground controllers identified it as an antenna cover from the Zvezda service module."

The object was an antenna cover from one of the low-gain WAL antennas on the space station used to help guide the European Space Agency's unmanned Automated Transfer Vehicle cargo ships during rendezvous and docking operations, NASA officials said.

An unidentified object floats near the International Space Station on August 19, 2013. 

Russian ground controllers later identified it as an antenna cover from the Zvezda service module.

Credit: NASA TV

NASA spokesman Josh Byerly told reporters that the wayward antenna cover, which is now space junk, poses no impact threat to the space station.

During a spacewalk outside the station today (Aug. 22), two Russian cosmonauts are inspecting six WAL antennas on the Zvezda module to check the positions of their covers.

The cosmonauts reported some of the covers to be loose and were expected to tighten them at a later date.

Friday, August 23, 2013

'Sail rover' could explore hellish Venus

A landing concept for a possible Venus windsurfing rover from the NASA Innovative Advanced Concepts office. Credit: NASA

A windsailing rover could use the high speeds and hot temperatures of Venus to a robotic explorer's advantage, according to an idea funded by NASA's Innovative Advanced Concepts program.

The rover would not only be able to move around Venus, but would also have electronics inside able to withstand the temperatures of 450 degrees Celsius (840 degrees Fahrenheit).

The rover, which is nicknamed Zephyr, would spend most of its time on Venus doing analysis on the ground.

Whenever the science team wants to move some distance, however, it would deploy a sail that could bring it across the surface. One vision sees it sailing for about 15 minutes a day for about a month.

"A sail rover would be extraordinary for Venus. The sail has only two moving parts-just to set the sail and set the steering position-and that doesn't require a lot of power. There's no power required to actually drive," stated Geoffrey Landis, who is with NASA's Glenn Research Center.

"The fundamental elements of a rover for Venus are not beyond the bounds of physics," Landis added. "We could survive the furnace of Venus if we can come up with an innovative concept for a rover that can move on extremely low power levels."

Landis has had many ideas for exploring Venus, including using a solar powered airplane and colonizing the planet using floating cities.

You can read more details about the windsurfing rover here. If this gets to the mission phase, this would represent the first time that any robot landed on Venus since the Soviet Venera landers; the last attempt was in the 1980s.

A fluffy disk around a baby star

Artist’s rendition of the "fluffy" layer associated with the protoplanetary disk of RY Tau, including jets coming from the star. 

Although typical young stars like RY Tau are often associated with jets, they are not visible in the HiCIAO observations at this time. 

Credit: NAOJ

An international team of astronomers that are members of the Strategic Exploration of Exoplanets and Disks with Subaru Telescope (SEEDS) Project has used Subaru Telescope's High Contrast Instrument for the Subaru Next Generation Adaptive Optics (HiCIAO) to observe a disk around the young star RY Tau (Tauri).

The team's analysis of the disk shows that a "fluffy" layer above it is responsible for the scattered light observed in the infrared image.

Detailed comparisons with computer simulations of scattered light from the disk reveal that this layer appears to be a remnant of material from an earlier phase of stellar and disk development, when dust and gas were falling onto the disk.

Since 2009, the five-year SEEDS Project has focused on direct imaging of exoplanets, i.e., planets orbiting stars outside of our Solar System, and disks around a targeted total of 500 stars.

Planet formation, an exciting and active area for astronomical research, has long fascinated many scientists.

Disks of dust and gas that rotate around young stars are of particular interest, because astronomers think that these are the sites where planets form—in these so-called "protoplanetary disks."

Since young stars and disks are born in molecular clouds, giant clouds of dust and gas, the role of dust becomes an important feature of understanding planet formation; it relates not only to the formation of rocky, Earth-like planets and the cores of giant Jupiter-like planets but also to that of moons, planetary rings, comets, and asteroids.

As a part of the SEEDS Project, the current team of researchers used HiCIAO mounted on the Subaru Telescope to observe a possible planet-forming disk around the young star RY Tau.

This star is about 460 light years away from Earth in the constellation Taurus and is around half a million years old.

The disk has a radius of about 70 AU (10 billion kilometers), which is a few times larger than the orbit of Neptune in our own Solar System.

More information: Takami, M. et al, 2013, High-Contrast Near-Infrared Imaging Polarimetry of the Protoplanetary Disk around RY Tau, Astrophysical Journal, Vol. 772, paper 145.

ISS EVA: Russian Cosmonauts Wave Russia's Flag in Orbit, Tackle Faulty Gear

A cosmonaut unfurls a Russian flag outside the International Space Station during a spacewalk on Aug. 22, 2013, to mark Russian Flag Day.

Credit: NASA TV

A misaligned piece of gear on the International Space Station caused headaches in orbit for two spacewalking cosmonauts today (Aug. 22), but they ultimately triumphed and even managed to celebrate Russia's Flag Day with orbital style.

Veteran cosmonaut Fyodor Yurchikhin proudly waved a Russian flag while soaring 260 miles (418 kilometers) above Earth to celebrate Russia's Flag Day holiday, which just happened to coincide with their nearly six-hour spacewalk.

"Congratulations to everyone on this day of the Russian flag," Yurchikhin said as he waved the flag in space. "Please remember to value and respect it, and we will respect ourselves."

Yurchikhin and fellow cosmonaut Alexander Misurkin let loose three "hoorahs" as they posed for TV and still cameras. They joked that some viewers wouldn't believe they were in space as the flag floated around them.

"It's a wonderful day," Yurchikhin quipped. "Some people might think that this is actually a performance. That this is staged somewhere down there … this is in space, as real as it comes."

The light-hearted moment capped a long day in orbit for Yurchikhin and Misurkin, who began their spacewalk at 7:36 a.m. EDT (1136 GMT).

They spent five hours and 58 minutes working outside on what was their second spacewalk in six days. The cosmonauts spent more than seven hours outside the station on Aug. 16, setting a new record for the longest Russian spacewalk.

Thursday, August 22, 2013

ESA NASA Hubble Images: Changes in a black-hole-powered jet of hot gas

This sequence of images, taken over a 13-year span by NASA's Hubble Space Telescope, reveals changes in a black-hole-powered jet of hot gas in the giant elliptical galaxy M87. 

The observations show that the river of plasma, traveling at nearly the speed of light, may follow the spiral structure of the black hole's magnetic field, which astronomers think is coiled like a helix. 

The magnetic field is believed to arise from a spinning accretion disk of material around a black hole. 

Although the magnetic field cannot be seen, its presence is inferred by the confinement of the jet along a narrow cone emanating from the black hole. 

The visible portion of the jet extends 5,000 light-years. M87 resides at the center of the neighboring Virgo cluster of roughly 2,000 galaxies, located 50 million light-years away. 

The images are part of a time-lapse movie that reveals changes in the jet over more than a 13-year period. 

They were taken by Hubble's Advanced Camera for Surveys in 2006 and Wide Field Planetary Camera 2 in 1995, 1998, 2001, and 2007. 

Credit: NASA, ESA, E. Meyer, W. Sparks, J. Biretta, J. Anderson, S.T. Sohn, and R. van der Marel (STScI), C. Norman (Johns Hopkins University), and M. Nakamura (Academia Sinica)

Russian ISS EVA: Spacewalkers stumped by faulty equipment

A pair of Russian cosmonauts on a spacewalk Thursday ran into equipment trouble while trying to swap an old laser experiment for a new telescope mount at the International Space Station and had to give up.

They were making their second spacewalk in under a week.

Ultimately, Russian Mission Control told Fyodor Yurchikhin and Aleksandr Misurkin to give up and bring the telescope platform back inside.

"We have different objectives. We cannot spend a lot of time here," one of the cosmonauts said.

The spacewalkers' remaining chore: inspecting six antennas attached to Russia's main space station compartment.

On Monday, an antenna cover came off and floated away. Russian space officials want to know which antenna lost its protective shield.

The spacewalkers also were checking the remaining covers to make sure they're secure. At least two were loose, one by a lot.

Unable to get enough leverage to properly use a screw driver, the cosmonauts could not tighten one of the covers.

Aleksandr Misurkin
The U.S. space agency said the flyaway cover posed no risk to the space station.

NASA, meanwhile, has suspended all U.S. spacewalks while the investigation into last month's near-drowning continues.

An Italian astronaut's helmet filled with water during a spacewalk on July 16. He barely made it back inside. The water is believed to have originated from the suit's cooling system.

Early in Thursday's spacewalk, Russian Mission Control jokingly blared a few seconds of pop music into the cosmonauts' headsets.

"You want to keep the music on the loop?" Mission Control asked. "Well, if it's possible, yes," one of the spacewalkers replied.

"Are you already that tired of me that you want to listen to music instead of my voice?" Mission Control teased.

The reply from orbit: "Please, we never get tired of you."

The swiveling platform was to hold an optical telescope that will be launched in November and installed by spacewalking cosmonauts.

This was the 173rd spacewalk at the space station, coming up on the 15th anniversary of the launch of its first part.

The four other space station residents—two Americans, one Italian and another Russian—watched the spacewalk from inside.

As for the defective spacesuit of Italian astronaut Luca Parmitano, NASA said it will return part or all of the outfit early next year on a commercial SpaceX capsule.

NASA LADEE Mission: Monitoring Lunar Dust

Artist’s concept of NASA's Lunar Atmosphere and Dust Environment Explorer (LADEE) spacecraft in orbit above the moon as dust scatters light during the lunar sunset. 

Credit: NASA Ames 

In partnership with NASA's Ames Research Center in Silicon Valley, Calif., Goddard's Wallops Flight Facility will launch the Lunar Atmosphere and Dust Environment Explorer (LADEE) in September, a robotic mission that will study the moon's thin atmosphere and dust particles.

Ames manages the 100-day mission—-which will attempt to confirm whether dust caused a mysterious glow on the lunar horizon astronauts observed during several Apollo missions—and Goddard plays a variety of key roles in LADEE.

After launch, Ames will control the spacecraft and execute mission operations. Goddard is responsible for the LADEE launch and several important LADEE components, including the instruments, demonstrations of the mission's payload and science operations.

"We wanted to do a mission that would benefit both centers," LADEE payload manager Robert Caffrey said. "It's a good model for centers working together to achieve common goals."

LADEE's launch in September from Virginia's Eastern Shore marks the facility's first launch to the moon.

Wallops will provide the launch services and range operations as well the launch vehicle, a U.S. Air Force Minotaur V rocket. LADEE will be the first spacecraft to launch on this rocket.

One of Goddard's biggest roles on LADEE is to manage the mission's four instruments and demonstrations. Three of the payload instruments—the Neutral Mass Spectrometer or NMS, Ultraviolet and Visible Light Spectrometer and the Lunar Dust Experiment or LDEX—will study the lunar atmosphere composition and analyze lunar dust.

Developed at Goddard, the NMS will measure variations in the different gases of the lunar atmosphere while the spacecraft orbits the moon. A similar spectrometer will fly aboard the Mars Atmosphere and Volatile Evolution Mission, scheduled to launch in November

"The Goddard Neutral Mass Spectrometer team is delighted to provide this instrument to the LADEE mission and contribute to this mission's exploration of the tenuous atmosphere of the moon," said Goddard NMS Principal Investigator Paul Mahaffy.

LADEE will also host the Lunar Laser Communications Demonstration or LLCD mission payload. LLCD is an innovative laser technology that could one day replace radio waves currently used in satellite communications and is expected to transmit more data at faster rates.

Solar Photographer Spots Giant Snake-Like Tendril on the Sun

Astrophotographer John Chumack took this photo of a solar filament. 

The image was taken from his backyard in Dayton, Ohio on Aug. 11, 2013.

Credit: John Chumack |

A photographer and die-hard solar observer has captured absolutely stunning views of a colossal filament of super-hot plasma snaking its way across the surface of the sun.

Veteran astrophotographer John Chumack took the new sun photos on Aug. 11 despite cloudy weather from his backyard in Dayton, Ohio, using a DMK 21 and DMK 31 Cameras and Lunt Hydrogen Alpha Solar Scope.

The close-up image is 1/77-second exposures and the full disk shots 1/436-second exposure.

What looks like a snake-like cloud in the new sun photos is actually a solar filament made of primarily charged hydrogen gas.

The sun’s magnetic field holds the gas in the atmosphere giving it the shape seen in these images.

The filament appears dark because it is cooler than its surroundings. These filaments might remain over the sun’s surface for months.

Former NASA astronaut and Test Pilot C. Gordon Fullerton dies

NASA says former space shuttle astronaut and test pilot C. Gordon Fullerton has died at age 76.

A NASA statement says Fullerton died Wednesday after spending most of the past 3 ½ years in a care facility in Lancaster, Calif., following a stroke in 2009.

Fullerton spent 382 hours in space on two space shuttle missions during his career as an astronaut from 1969 to 1986.

He was also a member of one of two crews that flew the shuttle prototype Enterprise on approach and landing tests in 1977.

Fullerton later spent 22 years as a test pilot on projects at NASA's Dryden Flight Research Center at Edwards Air Force Base.

The Portland, Ore., native joined the Air Force in 1958 and flew fighters and bombers before becoming a test pilot.