Friday, July 25, 2014

How Did Earth's Primitive Chemistry Get Kick Started?

How Did Earth's Primitive Chemistry Get Kick Started?:

This image from the floor of the Atlantic Ocean shows a collection of limestone towers known as the 'Lost City.'
This image from the floor of the Atlantic Ocean shows a collection of limestone towers known as the "Lost City." Alkaline hydrothermal vents of this type are suggested to be the birthplace of the first living organisms on the ancient Earth. Scientists are interested in understanding early life on Earth because if we ever hope to find life on other worlds - especially icy worlds with subsurface oceans such as Jupiter's moon Europa and Saturn's Enceladus - we need to know what chemical signatures to look for. Image courtesy D. Kelley and M. Elend/University of Washington
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July 30, 2013

How did life on Earth get started? Three new papers co-authored by Mike Russell, a research scientist at NASA's Jet Propulsion Laboratory, Pasadena, Calif., strengthen the case that Earth's first life began at alkaline hydrothermal vents at the bottom of oceans. Scientists are interested in understanding early life on Earth because if we ever hope to find life on other worlds -- especially icy worlds with subsurface oceans such as Jupiter's moon Europa and Saturn's Enceladus -- we need to know what chemical signatures to look for.


Two papers published recently in the journal Philosophical Transactions of the Royal Society B provide more detail on the chemical and precursor metabolic reactions that have to take place to pave the pathway for life. Russell and his co-authors describe how the interactions between the earliest oceans and alkaline hydrothermal fluids likely produced acetate (comparable to vinegar). The acetate is a product of methane and hydrogen from the alkaline hydrothermal vents and carbon dioxide dissolved in the surrounding ocean. Once this early chemical pathway was forged, acetate could become the basis of other biological molecules. They also describe how two kinds of "nano-engines" that create organic carbon and polymers -- energy currency of the first cells -- could have been assembled from inorganic minerals.


A paper published in the journal Biochimica et Biophysica Acta analyzes the structural similarity between the most ancient enzymes of life and minerals precipitated at these alkaline vents, an indication that the first life didn't have to invent its first catalysts and engines.


"Our work on alkaline hot springs on the ocean floor makes what we believe is the most plausible case for the origin of the life's building blocks and its energy supply," Russell said. "Our hypothesis is testable, has the right assortment of ingredients and obeys the laws of thermodynamics."


Russell's work was funded by the NASA Astrobiology Institute through the Icy Worlds team based at JPL, a division of the California Institute of Technology, Pasadena. The NASA Astrobiology Institute, based at NASA's Ames Research Center, Moffett Field, Calif., is a partnership among NASA, 15 U.S. teams and 13 international consortia. The Institute is part of NASA's astrobiology program, which supports research into the origin, evolution, distribution and future of life on Earth and the potential for life elsewhere.

Jia-Rui C. Cook 818-354-0850

Jet Propulsion Laboratory, Pasadena, Calif.

jccook@jpl.nasa.gov


2013-235

Spitzer Discovers Young Stars with a 'Hula Hoop'

Spitzer Discovers Young Stars with a 'Hula Hoop':

In this artist's impression, a disk of dusty material leftover from star formation girds two young stars like a hula hoop
In this artist's impression, a disk of dusty material leftover from star formation girds two young stars like a hula hoop. As the two stars whirl around each other, they periodically peek out from the disk, making the system appear to "blink" every 93 days. Image credit: NASA/JPL-Caltech
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July 31, 2013

Astronomers using NASA's Spitzer Space Telescope have spotted a young stellar system that "blinks" every 93 days. Called YLW 16A, the system likely consists of three developing stars, two of which are surrounded by a disk of material left over from the star-formation process.


As the two inner stars whirl around each other, they periodically peek out from the disk that girds them like a hula hoop. The hoop itself appears to be misaligned from the central star pair, probably due to the disrupting gravitational presence of the third star orbiting at the periphery of the system. The whole system cycles through bright and faint phases, with the central stars playing a sort of cosmic peek-a-boo as the tilted disk twirls around them. It is believed that this disk should go on to spawn planets and the other celestial bodies that make up a solar system.


Spitzer observed infrared light from YLW 16A, emitted by the warmed gas and dust in the disk that still swathes the young stars. Other observations came from the ground-based 2MASS survey, as well as from the NACO instrument at the European Southern Observatory's Very Large Telescope in Chile.


YLW 16A is the fourth example of a star system known to blink in such a manner, and the second in the same star-forming region Rho Ophiuchus. The finding suggests that these systems might be more common than once thought. Blinking star systems with warped disks offer scientists a way to study how planets form in these environments. The planets can orbit one or both of the stars in the binary star system. The famous science fictional planet Tatooine in "Star Wars" orbits two stars, hence its double sunsets. Such worlds are referred to as circumbinary planets. Astronomers can record how light is absorbed by planet-forming disks during the bright and faint phases of blinking stellar systems, which in turn reveals information about the materials that comprise the disk.


"These blinking systems offer natural probes of the binary and circumbinary planet formation process," said Peter Plavchan, a scientist at the NASA Exoplanet Science Institute and Infrared Processing and Analysis Center at the California Institute of Technology, Pasadena, Calif., and lead author of a new paper accepted for publication in Astronomy & Astrophysics.


NASA's Jet Propulsion Laboratory, Pasadena, Calif., manages the Spitzer Space Telescope mission for NASA's Science Mission Directorate, Washington. Science operations are conducted at the Spitzer Science Center at Caltech. Data are archived at the Infrared Science Archive housed at the Infrared Processing and Analysis Center. Caltech manages JPL for NASA. For more information about Spitzer, visit http://spitzer.caltech.edu and http://www.nasa.gov/spitzer .

Written by Adam Hadhazy

Contact:

Whitney Clavin 818-354-4673

Jet Propulsion Laboratory, Pasadena, Calif.

whitney.clavin@jpl.nasa.gov


2013-236

Monster Galaxies Lose Their Appetite With Age

Monster Galaxies Lose Their Appetite With Age:

This image shows two of the galaxy clusters observed by NASA's Wide-field Infrared Survey Explorer (WISE) and Spitzer Space Telescope missions
This image shows two of the galaxy clusters observed by NASA's Wide-field Infrared Survey Explorer (WISE) and Spitzer Space Telescope missions. Galaxy clusters are among the most massive structures in the universe. The central and largest galaxy in each grouping, called the brightest cluster galaxy or BCG, is seen at the center of each image. Image credit: NASA/JPL-Caltech/SDSS/NOAO

› Full image and caption

August 01, 2013

Our universe is filled with gobs of galaxies, bound together by gravity into larger families called clusters. Lying at the heart of most clusters is a monster galaxy thought to grow in size by merging with neighboring galaxies, a process astronomers call galactic cannibalism.


New research from NASA's Spitzer Space Telescope and Wide-field Infrared Survey Explorer (WISE) is showing that, contrary to previous theories, these gargantuan galaxies appear to slow their growth over time, feeding less and less off neighboring galaxies.


"We've found that these massive galaxies may have started a diet in the last 5 billion years, and therefore have not gained much weight lately," said Yen-Ting Lin of the Academia Sinica in Taipei, Taiwan, lead author of a study published in the Astrophysical Journal.


Peter Eisenhardt, a co-author from NASA's Jet Propulsion Laboratory in Pasadena, Calif., said, "WISE and Spitzer are letting us see that there is a lot we do understand -- but also a lot we don't understand -- about the mass of the most massive galaxies." Eisenhardt identified the sample of galaxy clusters studied by Spitzer, and is the project scientist for WISE.


The new findings will help researchers understand how galaxy clusters -- among the most massive structures in our universe -- form and evolve.


Galaxy clusters are made up of thousands of galaxies, gathered around their biggest member, what astronomers call the brightest cluster galaxy, or BCG. BCGs can be up to dozens of times the mass of galaxies like our own Milky Way. They plump up in size by cannibalizing other galaxies, as well as assimilating stars that are funneled into the middle of a growing cluster.


To monitor how this process works, the astronomers surveyed nearly 300 galaxy clusters spanning 9 billion years of cosmic time. The farthest cluster dates back to a time when the universe was 4.3 billion years old, and the closest, when the universe was much older, 13 billion years old (our universe is presently 13.8 billion years old).


"You can't watch a galaxy grow, so we took a population census," said Lin. "Our new approach allows us to connect the average properties of clusters we observe in the relatively recent past with ones we observe further back in the history of the universe."


Spitzer and WISE are both infrared telescopes, but they have unique characteristics that complement each other in studies like these. For instance, Spitzer can see more detail than WISE, which enables it to capture the farthest clusters best. On the other hand, WISE, an infrared all-sky survey, is better at capturing images of nearby clusters, thanks to its larger field of view. Spitzer is still up and observing; WISE went into hibernation in 2011 after successfully scanning the sky twice.


The findings showed that BCG growth proceeded along rates predicted by theories until 5 billion years ago, or a time when the universe was about 8 billion years old. After that time, it appears the galaxies, for the most part, stopped munching on other galaxies around them.


The scientists are uncertain about the cause of BCGs' diminished appetites, but the results suggest current models need tinkering.


"BCGs are a bit like blue whales -- both are gigantic and very rare in number. Our census of the population of BCGs is in a way similar to measuring how the whales gain their weight as they age. In our case, the whales aren't gaining as much weight as we thought. Our theories aren't matching what we observed, leading us to new questions," said Lin.


Another possible explanation is that the surveys are missing large numbers of stars in the more mature clusters. Clusters can be violent environments, where stars are stripped from colliding galaxies and flung into space. If the recent observations are not detecting those stars, it's possible that the enormous galaxies are, in fact, continuing to bulk up.


Future studies from Lin and others should reveal more about the feeding habits of one of nature's largest galactic species.


JPL manages the Spitzer Space Telescope mission for NASA's Science Mission Directorate, Washington. Science operations are conducted at the Spitzer Science Center at the California Institute of Technology in Pasadena. Data are archived at the Infrared Science Archive housed at the Infrared Processing and Analysis Center at Caltech. Caltech manages JPL for NASA. For more information about Spitzer, visit http://spitzer.caltech.edu and http://www.nasa.gov/spitzer .


JPL managed and operated WISE for NASA's Science Mission Directorate. Edward Wright is the principal investigator and is at UCLA. The mission was selected competitively under NASA's Explorers Program managed by the agency's Goddard Space Flight Center in Greenbelt, Md. The science instrument was built by the Space Dynamics Laboratory in Logan, Utah. The spacecraft was built by Ball Aerospace & Technologies Corp. in Boulder, Colo. Science operations and data processing take place at the Infrared Processing and Analysis Center at the California Institute of Technology in Pasadena. Caltech manages JPL for NASA. More information is online at http://www.nasa.gov/wise and http://wise.astro.ucla.edu and http://jpl.nasa.gov/wise .

Whitney Clavin 818-354-4673

Jet Propulsion Laboratory, Pasadena, Calif.

whitney.clavin@jpl.nasa.gov


2013-239

Swapping Motion-Sensing Units

Swapping Motion-Sensing Units:

Artist concept of Mars Reconnaissance Orbiter. Image credit: NASA/JPL
Artist concept of Mars Reconnaissance Orbiter. Image credit: NASA/JPL
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August 12, 2013

Mars Reconnaissance Orbiter Mission Status Report


PASADENA, Calif. -- NASA's Mars Reconnaissance Orbiter is switching from one motion-sensing device to a duplicate unit onboard.


The veteran orbiter relies on this inertial measurement unit (IMU) for information about changes in orientation. This information is important for maintaining spacecraft attitude and for pointing the orbiter's large antenna and science-observation instruments.


The spacecraft has two identical copies of this motion-sensing device, called IMU-1 and IMU-2. Either of them can be used with either of the spacecraft's redundant main computers. Each contains three gyroscopes and three accelerometers.


"The reason we're doing this is that one of the gyroscopes on IMU-1 is approaching its end of life, so we want to swap to our redundant unit early enough that we still have some useful life preserved in the first unit," said Mars Reconnaissance Orbiter Mission Manager Reid Thomas of NASA's Jet Propulsion Laboratory, Pasadena, Calif.


The orbiter began investigating Mars in 2006. Since completing its primary science phase in 2008, it has continued to work as an extended mission.


The swap has been planned for this week, with procedures expected to take less than two days before the orbiter resumes its normal functions of science observations from orbit and communication relay for Mars rovers.


"To make sure we have a smooth transition, regaining attitude knowledge as quickly as possible, we will power off all instruments, do the IMU swap, maneuver to sun point, do the IMU swap, and then put the spacecraft into safe mode," Thomas said. "The safe-mode process re-initializes the spacecraft's knowledge of its attitude."


IMU-2 has been used previously, but IMU-1 has been used much more. After the swap, IMU-1 will remain available if needed for short periods.


The Mars Reconnaissance Orbiter has provided more data about Mars than all other earlier and current missions combined. It also relays to Earth information from both of NASA's active Mars rovers, Opportunity and Curiosity, sharing that function with the NASA Mars Odyssey orbiter.


JPL, a division of the California Institute of Technology in Pasadena, manages the Mars Reconnaissance Orbiter for NASA's Science Mission Directorate, Washington. Lockheed Martin Space Systems, Denver, built the orbiter and partners in its daily operation.


More information about the Mars Reconnaissance Orbiter is available online at http://mars.jpl.nasa.gov/mro/ .

Guy Webster 818-354-6278

Jet Propulsion Laboratory, Pasadena, Calif.

guy.webster@jpl.nasa.gov


2013-245

If We Landed on Europa, What Would We Want to Know?

If We Landed on Europa, What Would We Want to Know?:

Simulated View from Europa's Surface (Artist's Concept)
This artist's concept shows a simulated view from the surface of Jupiter's moon Europa. Europa's potentially rough, icy surface, tinged with reddish areas that scientists hope to learn more about, can be seen in the foreground. The giant planet Jupiter looms over the horizon. Image credit: NASA/JPL-Caltech

› Full image and caption

August 07, 2013

Most of what scientists know of Jupiter's moon Europa they have gleaned from a dozen or so close flybys from NASA's Voyager 2 spacecraft in 1979 and NASA's Galileo spacecraft in the mid-to-late 1990s. Even in these fleeting, paparazzi-like encounters, scientists have seen a fractured, ice-covered world with tantalizing signs of a liquid water ocean under its surface. Such an environment could potentially be a hospitable home for microbial life. But what if we got to land on Europa's surface and conduct something along the lines of a more in-depth interview? What would scientists ask? A new study in the journal Astrobiology authored by a NASA-appointed science definition team lays out their consensus on the most important questions to address.


"If one day humans send a robotic lander to the surface of Europa, we need to know what to look for and what tools it should carry," said Robert Pappalardo, the study's lead author, based at NASA's Jet Propulsion Laboratory, Pasadena, Calif. "There is still a lot of preparation that is needed before we could land on Europa, but studies like these will help us focus on the technologies required to get us there, and on the data needed to help us scout out possible landing locations. Europa is the most likely place in our solar system beyond Earth to have life today, and a landed mission would be the best way to search for signs of life."


The paper was authored by scientists from a number of other NASA centers and universities, including the Johns Hopkins University Applied Physics Laboratory, Laurel, Md.; University of Colorado, Boulder; University of Texas, Austin; and the NASA Goddard Space Flight Center, Greenbelt, Md. The team found the most important questions clustered around composition: what makes up the reddish "freckles" and reddish cracks that stain the icy surface? What kind of chemistry is occurring there? Are there organic molecules, which are among the building blocks of life?

Additional priorities involved improving our images of Europa - getting a look around at features on a human scale to provide context for the compositional measurements. Also among the top priorities were questions related to geological activity and the presence of liquid water: how active is the surface? How much rumbling is there from the periodic gravitational squeezes from its planetary host, the giant planet Jupiter? What do these detections tell us about the characteristics of liquid water below the icy surface?


"Landing on the surface of Europa would be a key step in the astrobiological investigation of that world," said Chris McKay, a senior editor of the journal Astrobiology, who is based at NASA Ames Research Center, Moffett Field, Calif. "This paper outlines the science that could be done on such a lander. The hope would be that surface materials, possibly near the linear crack features, include biomarkers carried up from the ocean."


This work was conducted with Europa study funds from NASA's Science Mission Directorate, Washington, D.C. JPL is a division of the California Institute of Technology, Pasadena.

Jia-Rui C. Cook 818-354-0850

Jet Propulsion Laboratory, Pasadena, Calif.

jccook@jpl.nasa.gov


2013-243

Surface impressions of Rosetta's comet

Surface impressions of Rosetta's comet:

Rotating Shape Model of Rosetta's Comet Target
Images of comet 67P/Churyumov-Gerasimenko taken on July 14, 2014, by the OSIRIS imaging system aboard the European Space Agency's Rosetta spacecraft have allowed scientists to create this three-dimensional shape model of the nucleus. Image credit: ESA/Rosetta/MPS for OSIRIS Team/MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA

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July 24, 2014

Surface structures are becoming visible in new images of comet 67P/Churyumov-Gerasimenko taken by the scientific imaging system OSIRIS onboard the European Space Agency's Rosetta spacecraft. The resolution of these images is now 330 feet (100 meters) per pixel. One of the most striking features is currently found in the comet's neck region. This part of 67P seems to be brighter than the rest of the nucleus.

As earlier images had already shown, 67P may consist of two parts: a smaller head connected to a larger body. The connecting region, the neck, is proving to be especially intriguing. "The only thing we know for sure at this point is that this neck region appears brighter compared to the head and body of the nucleus," says OSIRIS Principal Investigator Holger Sierks from the Max Planck Institute for Solar System Research in Germany. This collar-like appearance could be caused by differences in material or grain size, or could be a topographical effect.

Even though the images taken from a distance of 3,400 miles (5,500 kilometers) are still not highly resolved, the scientists are remotely reminded of comet 103P/Hartley, which was visited in a flyby by NASA's EPOXI mission in 2010. While Hartley's ends show a rather rough surface, its middle is much smoother. Scientists believe this waist to be a gravitational low: since it contains the body's center of mass, emitted material that cannot leave the comet's gravitational field is most likely to be re-deposited there.

Whether this also holds true for 67P's neck region is still unclear. Another explanation for the high reflectivity could be a different surface composition. In coming weeks, the OSIRIS team hopes to analyze the spectral data of this region obtained with the help of the imaging system's filters. These can select several wavelength regions from the reflected light, allowing scientists to identify the characteristic fingerprints of certain materials and compositional features.

At the same time, the team is currently modeling the comet's three-dimensional shape from the camera data. Such a model can help to get a better impression of the body's shape.

Rosetta will be the first mission in history to rendezvous with a comet, escort it as it orbits the sun, and deploy a lander to its surface.

Rosetta's Philae lander is provided by a consortium led by the German Aerospace Center, Cologne; Max Planck Institute for Solar System Research, Gottingen; French National Space Agency, Paris; and the Italian Space Agency, Rome. The Jet Propulsion Laboratory, a division of the California Institute of Technology, Pasadena, manages the U.S. participation in the Rosetta mission for NASA's Science Mission Directorate in Washington. Rosetta carries three NASA instruments in its 21-instrument payload.

For more information on the U.S. instruments aboard Rosetta, visit:

http://rosetta.jpl.nasa.gov

More information about Rosetta is available at:

http://www.esa.int/rosetta

Preston Dyches

Jet Propulsion Laboratory, Pasadena, Calif.

818-354-7013

preston.dyches@jpl.nasa.gov


Dwayne Brown

NASA Headquarters

202-358-1726

dwayne.c.brown@nasa.gov


Markus Bauer
European Space Agency, Noordwijk, Netherlands

011-31-71-565-6799

markus.bauer@esa.int


Birgit Krummheuer

Max Planck Institute for Solar System Research

011-49-551-384-979-462

krummheuer@mps.mpg.de


2014-243

Wednesday, July 23, 2014

NASA Rover Gets Movie as a Mars Moon Passes Another

NASA Rover Gets Movie as a Mars Moon Passes Another:

Illustration Comparing Apparent Sizes of Moons
This illustration provides a comparison for how big the moons of Mars appear to be, as seen from the surface of Mars, in relation to the size that Earth's moon appears to be when seen from the surface of Earth. Earth's moon actually has a diameter more than 100 times greater than the larger Martian moon, Phobos. However, the Martian moons orbit much closer to their planet than the distance between Earth and Earth's moon. Credit: NASA/JPL-Caltech/Malin Space Science Systems/Texas A&M Univ.
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August 15, 2013

PASADENA, Calif. -- The larger of the two moons of Mars, Phobos, passes directly in front of the other, Deimos, in a new series of sky-watching images from NASA's Mars rover Curiosity.


A video clip assembled from the images is at http://youtu.be/DaVSCmuOJwI .


Large craters on Phobos are clearly visible in these images from the surface of Mars. No previous images from missions on the surface caught one moon eclipsing the other.


The telephoto-lens camera of Curiosity's two-camera Mast Camera (Mastcam) instrument recorded the images on Aug. 1. Some of the full-resolution frames were not downlinked until more than a week later, in the data-transmission queue behind higher-priority images being used for planning the rover's drives.


These observations of Phobos and Deimos help researchers make knowledge of the moons' orbits even more precise.


"The ultimate goal is to improve orbit knowledge enough that we can improve the measurement of the tides Phobos raises on the Martian solid surface, giving knowledge of the Martian interior," said Mark Lemmon of Texas A&M University, College Station. He is a co-investigator for use of Curiosity's Mastcam. "We may also get data good enough to detect density variations within Phobos and to determine if Deimos' orbit is systematically changing."


The orbit of Phobos is very slowly getting closer to Mars. The orbit of Deimos may be slowly getting farther from the planet.


Lemmon and colleagues determined that the two moons would be visible crossing paths at a time shortly after Curiosity would be awake for transmitting data to NASA's Mars Reconnaissance Orbiter for relay to Earth. That made the moon observations feasible with minimal impact on the rover's energy budget.


Although Phobos has a diameter less than one percent the diameter of Earth's moon, Phobos also orbits much closer to Mars than our moon's distance from Earth. As seen from the surface of Mars, Phobos looks about half as wide as what Earth's moon looks like to viewers on Earth.


NASA's Mars Science Laboratory project is using Curiosity and the rover's 10 science instruments to investigate the environmental history within Gale Crater, a location where the project has found that conditions were long ago favorable for microbial life.


Malin Space Science Systems, San Diego, built and operates Curiosity's Mastcam. JPL, a division of the California Institute of Technology in Pasadena, manages the project for NASA's Science Mission Directorate in Washington and built the Navigation Camera and the rover.


More information about the mission is online at: http://www.jpl.nasa.gov/msl , http://www.nasa.gov/msl and http://mars.jpl.nasa.gov/msl/ .


You can follow the mission on Facebook and Twitter at: http://www.facebook.com/marscuriosity and http://www.twitter.com/marscuriosity .


For more information about the Multi-Mission Image Processing Laboratory, see:
http://www-mipl.jpl.nasa.gov/mipex.html .

Guy Webster 818-354-6278

Jet Propulsion Laboratory, Pasadena, Calif.

guy.webster@jpl.nasa.gov


2013-253

NASA Voyager Statement about Competing Models to Explain Recent Spacecraft Data

NASA Voyager Statement about Competing Models to Explain Recent Spacecraft Data:

Voyager the Explorer
This artist's concept shows NASA's Voyager spacecraft against a field of stars in the darkness of space. The two Voyager spacecraft are traveling farther and farther away from Earth, on a journey to interstellar space, and will eventually circle around the center of the Milky Way galaxy. Image credit:
NASA/JPL-Caltech
› Full image and caption

August 15, 2013

A newly published paper argues that NASA's Voyager 1 spacecraft has already entered interstellar space. The model described in the paper is new and different from other models used so far to explain the data the spacecraft has been sending back from more than 11 billion miles (18 billion kilometers) away from our sun.


NASA's Voyager project scientist, Ed Stone of the California Institute of Technology in Pasadena, explains:


"Details of a new model have just been published that lead the scientists who created the model to argue that NASA's Voyager 1 spacecraft data can be consistent with entering interstellar space in 2012. In describing on a fine scale how magnetic field lines from the sun and magnetic field lines from interstellar space can connect to each other, they conclude Voyager 1 has been detecting the interstellar magnetic field since July 27, 2012. Their model would mean that the interstellar magnetic field direction is the same as that which originates from our sun.


Other models envision the interstellar magnetic field draped around our solar bubble and predict that the direction of the interstellar magnetic field is different from the solar magnetic field inside. By that interpretation, Voyager 1 would still be inside our solar bubble.


The fine-scale magnetic connection model will become part of the discussion among scientists as they try to reconcile what may be happening on a fine scale with what happens on a larger scale.


The Voyager 1 spacecraft is exploring a region no spacecraft has ever been to before. We will continue to look for any further developments over the coming months and years as Voyager explores an uncharted frontier."


The Voyager spacecraft were built and continue to be operated by NASA's Jet Propulsion Laboratory, in Pasadena, Calif. Caltech manages JPL for NASA. The Voyager missions are a part of NASA's Heliophysics System Observatory, sponsored by the Heliophysics Division of the Science Mission Directorate at NASA Headquarters in Washington.


For more information about Voyager, visit: http://www.nasa.gov/voyager and
http://voyager.jpl.nasa.gov .

Jia-Rui Cook 818-354-0850

Jet Propulsion Laboratory, Pasadena, Calif.

jccook@jpl.nasa.gov


2013-251

Radar Images of Asteroid 2005 WK4

Radar Images of Asteroid 2005 WK4:

Radar images of asteroid 2005 WK4 were obtained on Aug. 8, 2013.
Radar images of asteroid 2005 WK4 were obtained on Aug. 8, 2013. The asteroid is between 660 - 980 feet (200 - 300 meters) in diameter. Image credit: NASA/JPL-Caltech/GSSR
› Larger image

August 15, 2013

PASADENA, Calif. -- A collage of radar images of near-Earth asteroid 2005 WK4 was generated by NASA scientists using the 230-foot (70-meter) Deep Space Network antenna at Goldstone, Calif., on Aug. 8, 2013.


The asteroid is between 660 and 980 feet (200 and 300 meters) in diameter; it has a rounded and slightly asymmetric shape. As it rotates, a number of features are evident that suggest the presence of some flat regions and a bulge near the equator.


The radar observations of 2005 WK4 were led by scientist Lance Benner of NASA's Jet Propulsion Laboratory, Pasadena, Calif. The data were obtained between 12:40 and 7:10 a.m. PDT (3:40 and 10:10 a.m. EDT). At the time of the observations, the asteroid's distance was about 1.93 million miles (3.1 million kilometers) from Earth, which is 8.2 lunar distances away. The data were obtained over an interval of 6.5 hours as the asteroid completed about 2.4 rotations. The resolution is 12 feet (3.75 meters) per pixel.


Radar is a powerful technique for studying an asteroid's size, shape, rotation state, surface features and surface roughness, and for improving the calculation of asteroid orbits. Radar measurements of asteroid distances and velocities often enable computation of asteroid orbits much further into the future than if radar observations weren't available.


NASA places a high priority on tracking asteroids and protecting our home planet from them. In fact, the United States has the most robust and productive survey and detection program for discovering near-Earth objects. To date, U.S. assets have discovered more than 98 percent of the known near-Earth Objects.


In addition to the resources NASA puts into understanding asteroids, it also partners with other U.S. government agencies, university-based astronomers, and space science institutes across the country that are working to track and understand these objects better, often with grants, interagency transfers and other contracts from NASA.


In 2016, NASA will launch a robotic probe to one of the most potentially hazardous of the known near-Earth objects. The OSIRIS-REx mission to asteroid (101955) Bennu will be a pathfinder for future spacecraft designed to perform reconnaissance on any newly discovered threatening objects. Aside from monitoring potential threats, the study of asteroids and comets enables a valuable opportunity to learn more about the origins of our solar system, the source of water on Earth, and even the origin of organic molecules that led to the development of life.


NASA recently announced development of a first-ever mission to identify, capture and relocate an asteroid for human exploration. Using game-changing technologies, this mission would mark an unprecedented technological achievement that raises the bar of what humans can do in space.


NASA's Near-Earth Object Program at NASA Headquarters, Washington, manages and funds the search, study and monitoring of asteroids and comets whose orbits periodically bring them close to Earth. JPL manages the Near-Earth Object Program Office for NASA's Science Mission Directorate in Washington. JPL is a division of the California Institute of Technology in Pasadena.


More information about asteroids and near-Earth objects is available at: http://neo.jpl.nasa.gov/ , http://www.jpl.nasa.gov/asteroidwatch and via Twitter at http://www.twitter.com/asteroidwatch .


More information about asteroid radar research is at: http://echo.jpl.nasa.gov/ .


More information about the Deep Space Network is at: http://deepspace.jpl.nasa.gov/dsn .

DC Agle 818-393-9011

Jet Propulsion Laboratory, Pasadena, Calif.

agle@jpl.nasa.gov


2013-254

Cassini Releases Image of Earth Waving at Saturn

Cassini Releases Image of Earth Waving at Saturn:

Earth Waves at Cassini
From more than 40 countries and 30 U.S. states, people around the world shared more than 1,400 images of themselves as part of the Wave at Saturn event organized by NASA's Cassini mission. That event on July 19, 2013, marked the day the Cassini spacecraft turned back toward Earth to take our picture as part of a larger mosaic of the Saturn system. The images came via Twitter, Facebook, Flickr, Instagram, Google+ and email. The mission has assembled this collage from the shared images, using an image of Earth as the base image.
Image credit: NASA/JPL-Caltech

› Larger image

August 21, 2013

PASADENA, Calif. - People around the world shared more than 1,400 images of themselves as part of the Wave at Saturn event organized by NASA's Cassini mission on July 19 -- the day the Cassini spacecraft turned back toward Earth to take our picture. The mission has assembled a collage from those images. The collage is online at: http://www.nasa.gov/mission_pages/cassini/multimedia/collage2013.html .


"Thanks to all of you, near and far, old and young, who joined the Cassini mission in marking the first time inhabitants of Earth had advance notice that our picture was being taken from interplanetary distances," said Linda Spilker, Cassini project scientist at NASA's Jet Propulsion Laboratory, Pasadena, Calif. "While Earth is too small in the images Cassini obtained to distinguish any individual human beings, the mission has put together this collage so that we can celebrate all your waving hands, uplifted paws, smiling faces and artwork."


The images came from 40 countries and 30 U.S. states via Twitter, Facebook, Flickr, Instagram, Google+ and email.


From its perch in the Saturn system, Cassini took a picture of Earth as part of a larger set of images it was collecting of the Saturn system. Scientists are busy putting together the color mosaic of the Saturn system, which they expect will take at least several more weeks to complete. The scientists who study Saturn's rings are poring over visible-light and infrared data obtained during that campaign.


For more information on the Wave at Saturn campaign, visit: http://saturn.jpl.nasa.gov/waveatsaturn .


The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. JPL, a division of the California Institute of Technology, Pasadena, manages the mission for NASA's Science Mission Directorate in Washington.


For more information about the Cassini mission, visit: http://www.nasa.gov/cassini and http://saturn.jpl.nasa.gov .

Jia-Rui Cook 818-354-0850

Jet Propulsion Laboratory, Pasadena, Calif.

jccook@jpl.nasa.gov


2013-256

Littlest Continent Had Biggest Role in Sea Level Drop

Littlest Continent Had Biggest Role in Sea Level Drop:

Australia, combined with the continent's soils and unique topography
Changes in Australia's mass as reported by data from NASA's Gravity Recovery and Climate Experiment (GRACE) satellites from June 2010 to February 2011. Areas in greens and blues depict the greatest increases in mass, caused by excessive precipitation. The contour lines represent various land surface elevations. A new study co-authored and co-funded by NASA finds extensive flooding in Australia, combined with the continent's soils and unique topography, were the biggest contributors to the drop in global sea level observed in 2010 and 2011. Credit: NCAR/NASA/JPL-Caltech

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August 19, 2013

A unique and complex set of circumstances came together over Australia from 2010 to 2011 to cause Earth's smallest continent to be the biggest contributor to the observed drop in global sea level rise during that time, finds a new study co-authored and co-funded by NASA.


In 2011, scientists at NASA's Jet Propulsion Laboratory in Pasadena, Calif., and the University of Colorado at Boulder reported that between early 2010 and summer 2011, global sea level fell sharply, by about a quarter of an inch, or half a centimeter. Using data from the NASA/German Aerospace Center's Gravity Recovery and Climate Experiment (GRACE) spacecraft, they showed that the drop was caused by the very strong La Nina that began in late 2010. That La Nina changed rainfall patterns all over our planet, moving huge amounts of Earth's water from the ocean to the continents. The phenomenon was short-lived, however.


By mid-2012, global mean sea level had resumed its long-term mean annual rise of 0.13 inches (3.2 millimeters) per year (see http://www.jpl.nasa.gov/news/news.php?release=2012-362 ).


But analyses of the historical record showed that past La Nina events only rarely accompanied such a pronounced drop in sea level. So what made this particular La Nina unique?


To better understand this phenomenon, scientists at the National Center for Atmospheric Research (NCAR) in Boulder, Colo.; JPL; and the University of Colorado at Boulder combined GRACE data with data from the Argo global array of 3,000 free-drifting floats and satellite altimeters (Jason-1, Jason-2 and Topex/Poseidon).


They found that three atmospheric patterns converged over the Indian and Pacific Oceans in 2010 and 2011 to drive excessive precipitation over Australia. On average, the continent received almost one foot (300 millimeters) of rain more than normal. The result was widespread flooding. The flooding was in large part prevented from running back into the ocean by Australia's dry soils and the mountain-ringed topography of the country's vast interior, called the Outback, leading to the measurable drop in the world's ocean levels.


"No other continent has this combination of atmospheric set-up and topography," said NCAR scientist John Fasullo, lead author of the study. "Only in Australia could the atmosphere carry such heavy tropical rains to such a large area, only to have those rains fail to make their way to the ocean."


Now that the atmospheric patterns have snapped back and more rain is falling over tropical oceans, the seas are rising again. In fact, with Australia in a major drought, they are rising faster than before. Since 2011, when the atmospheric patterns shifted out of their unusual combination, sea levels have been rising at a faster pace of about 0.4 inches (10 millimeters) per year.


The study, co-funded by NASA and the National Science Foundation, will be published next month in the journal Geophysical Research Letters.


For more information, read the full NCAR news release: http://www2.ucar.edu/atmosnews/news/10090/global-sea-level-rise-dampened-australia-floods .

Alan Buis 818-354-0474

Jet Propulsion Laboratory, Pasadena, Calif.

alan.buis@jpl.nasa.gov


David Hosansky 303-497-8611

National Center for Atmospheric Research, Boulder, Colo.

hosansky@ucar.edu


2013-255

NASA Spacecraft Reactivated to Hunt for Asteroids

NASA Spacecraft Reactivated to Hunt for Asteroids:

Back to Hunt More Asteroids
This artist's concept shows the Wide-field Infrared Survey Explorer, or WISE spacecraft, in its orbit around Earth. In September of 2013, engineers will attempt to bring the mission out of hibernation to hunt for more asteroids and comets in a project called NEOWISE. Image credit: NASA/JPL-Caltech
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August 21, 2013

Probe Will Assist Agency in Search for Candidates to Explore


PASADENA, Calif. -- A NASA spacecraft that discovered and characterized tens of thousands of asteroids throughout the solar system before being placed in hibernation will return to service for three more years starting in September, assisting the agency in its effort to identify the population of potentially hazardous near-Earth objects, as well as those suitable for asteroid exploration missions.


The Wide-field Infrared Survey Explorer (WISE) will be revived next month with the goal of discovering and characterizing near-Earth objects (NEOs), space rocks that can be found orbiting within 28 million miles (45 million kilometers) from Earth's path around the sun. NASA anticipates WISE will use its 16-inch (40-centimeter) telescope and infrared cameras to discover about 150 previously unknown NEOs and characterize the size, albedo and thermal properties of about 2,000 others -- including some which could be candidates for the agency's recently announced asteroid initiative.


"The WISE mission achieved its mission's goals and as NEOWISE extended the science even further in its survey of asteroids. NASA is now extending that record of success, which will enhance our ability to find potentially hazardous asteroids, and support the new asteroid initiative," said John Grunsfeld, NASA's associate administrator for science in Washington. "Reactivating WISE is an excellent example of how we are leveraging existing capabilities across the agency to achieve our goal."


NASA's asteroid initiative will be the first mission to identify, capture and relocate an asteroid. It represents an unprecedented technological feat that will lead to new scientific discoveries and technological capabilities that will help protect our home planet. The asteroid initiative brings together the best of NASA's science, technology and human exploration efforts to achieve President Obama's goal of sending humans to an asteroid by 2025.


Launched in December 2009 to look for the glow of celestial heat sources from asteroids, stars and galaxies, WISE made about 7,500 images every day during its primary mission, from January 2010 to February 2011. As part of a project called NEOWISE, the spacecraft made the most accurate survey to date of NEOs. NASA turned most of WISE's electronics off when it completed its primary mission.


"The data collected by NEOWISE two years ago have proven to be a gold mine for the discovery and characterization of the NEO population," said Lindley Johnson, NASA's NEOWISE program executive in Washington. "It is important that we accumulate as much of this type of data as possible while the WISE spacecraft remains a viable asset."


Because asteroids reflect but do not emit visible light, infrared sensors are a powerful tool for discovering, cataloging and understanding the asteroid population. Depending on an object's reflectivity, or albedo, a small, light-colored space rock can look the same as a big, dark one. As a result, data collected with optical telescopes using visible light can be deceiving.


During 2010, NEOWISE observed about 158,000 rocky bodies out of approximately 600,000 known objects. Discoveries included 21 comets, more than 34,000 asteroids in the main belt between Mars and Jupiter, and 135 near-Earth objects.


The WISE prime mission was to scan the entire celestial sky in infrared light. It captured more than 2.7 million images in multiple infrared wavelengths and cataloged more than 560 million objects in space, ranging from galaxies faraway to asteroids and comets much closer to Earth.


"The team is ready and after a quick checkout, we're going to hit the ground running," said Amy Mainzer, NEOWISE principal investigator at NASA's Jet Propulsion Laboratory in Pasadena, Calif. "NEOWISE not only gives us a better understanding of the asteroids and comets we study directly, but it will help us refine our concepts and mission operation plans for future, space-based near-Earth object cataloging missions."


JPL manages WISE for NASA's Science Mission Directorate at the agency's headquarters in Washington. The mission is part of NASA's Explorers Program, which NASA's Goddard Space Flight Center in Greenbelt, Md., manages. The Space Dynamics Laboratory in Logan, Utah, built the science instrument. Ball Aerospace & Technologies Corp. of Boulder, Colo., built the spacecraft. Science operations and data processing take place at the Infrared Processing and Analysis Center at the California Institute of Technology in Pasadena. Caltech manages JPL for NASA.


More information about NEOWISE is available online at: http://www.nasa.gov/wise and http://www.jpl.nasa.gov/wise/ .


For more information on the asteroid initiative, visit: http://www.nasa.gov/asteroidinitiative .

DC Agle 818-393-9011

Jet Propulsion Laboratory, Pasadena, Calif.

agle@jpl.nasa.gov


Dwayne Brown 202-358-1726

NASA Headquarters, Washington

Dwayne.c.brown@nasa.gov


2013-257

NASA Mars Rover Views Eclipse of the Sun by Phobos

NASA Mars Rover Views Eclipse of the Sun by Phobos:

Annular Eclipse of the Sun by Phobos, as Seen by Curiosity
This set of three images shows views three seconds apart as the larger of Mars' two moons, Phobos, passed directly in front of the sun as seen by NASA's Mars rover Curiosity. Curiosity photographed this annular, or ring, eclipse with the telephoto-lens camera of the rover's Mast Camera pair (right Mastcam) on Aug. 20, 2013, the 369th Martian day, or sol, of Curiosity's work on Mars. Image credit: NASA/JPL-Caltech/Malin Space Science Systems/Texas A&M Univ.
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August 28, 2013

PASADENA, Calif. - Images taken with a telephoto-lens camera on NASA's Mars rover Curiosity catch the larger of Mars' two moons, Phobos, passing directly in front of the sun -- the sharpest images of a solar eclipse ever taken at Mars.


Phobos does not fully cover the sun, as seen from the surface of Mars, so the solar eclipse is what's called a ring, or annular, type. A set of three frames from Curiosity's Mast Camera (Mastcam), taken three seconds apart as Phobos eclipsed the sun, is at http://www.jpl.nasa.gov/spaceimages/details.php?id=PIA17356 .


The images are the first full-resolution frames downlinked to Earth from an Aug. 20, 2013, series. The series may later provide a movie of the eclipse. Curiosity paused during its drive that day to record the sky-watching images.


"This event occurred near noon at Curiosity's location, which put Phobos at its closest point to the rover, appearing larger against the sun than it would at other times of day," said Mark Lemmon of Texas A&M University, College Station, a co-investigator for use of Curiosity's Mastcam. "This is the closest to a total eclipse of the sun that you can have from Mars."


Observations of the Martian moons, Phobos and Deimos, by Curiosity and by the older, still-active Mars rover Opportunity are helping researchers get more precise knowledge of the moons' orbits. During the Aug. 20 observation, the position of Phobos crossing the sun was a mile or two (two or three kilometers) closer to the center of the sun's position than researchers anticipated.


Lemmon said, "This one is by far the most detailed image of any Martian lunar transit ever taken, and it is especially useful because it is annular. It was even closer to the sun's center than predicted, so we learned something."


NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology, manages the Mars Science Laboratory Project for NASA's Science Mission Directorate, Washington. JPL designed and built the project's Curiosity rover.


Malin Space Science Systems, San Diego, built and operates the Mastcam instrument and two other instruments on Curiosity.


More information about Curiosity is online at http://www.jpl.nasa.gov/msl , http://www.nasa.gov/msl and http://mars.jpl.nasa.gov/msl/ . You can follow the mission on Facebook at http://www.facebook.com/marscuriosity and on Twitter at http://www.twitter.com/marscuriosity .

Guy Webster 818-354-6278

Jet Propulsion Laboratory, Pasadena, Calif.

guy.webster@jpl.nasa.gov


2013-263

NASA-Funded Scientists Detect Water on Moon's Surface that Hints at Water Below

NASA-Funded Scientists Detect Water on Moon's Surface that Hints at Water Below:

This image of the moon was generated by data collected by NASA's Moon Mineralogy Mapper
This image of the moon was generated by data collected by NASA's Moon Mineralogy Mapper on the Indian Space Research Organization's Chandrayaan-1 mission. It is a three-color composite of reflected near-infrared radiation from the sun, and illustrates the extent to which different materials are mapped across the side of the moon that faces Earth. Image credit: ISRO/NASA/JPL-Caltech/Brown Univ./USGS
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August 28, 2013

PASADENA - NASA-funded lunar research has yielded evidence of water locked in mineral grains on the surface of the moon from an unknown source deep beneath the surface. Using data from NASA's Moon Mineralogy Mapper (M3) instrument aboard the Indian Space Research Organization's Chandrayaan-1 spacecraft, scientists remotely detected magmatic water, or water that originates from deep within the moon's interior, on the surface of the moon.


The findings, published Aug. 25 in Nature Geoscience, represent the first detection of this form of water from lunar orbit. Earlier studies had shown the existence of magmatic water in lunar samples returned during NASA's Apollo program.


M3 imaged the lunar impact crater Bullialdus, which lies near the lunar equator. Scientists were interested in studying this area because they could better quantify the amount of water inside the rocks due to the crater's location and the type of rocks it held. The central peak of the crater is made up of a type of rock that forms deep within the lunar crust and mantle when magma is trapped underground.


"This rock, which normally resides deep beneath the surface, was excavated from the lunar depths by the impact that formed Bullialdus crater," said Rachel Klima, a planetary geologist at the Johns Hopkins University Applied Physics Laboratory (APL) in Laurel, Md.


"Compared to its surroundings, we found that the central portion of this crater contains a significant amount of hydroxyl - a molecule consisting of one oxygen atom and one hydrogen atom -- which is evidence that the rocks in this crater contain water that originated beneath the lunar surface," Klima said.


In 2009, M3 provided the first mineralogical map of the lunar surface and discovered water molecules in the polar regions of the moon. This water is thought to be a thin layer formed from solar wind hitting the moon's surface. Bullialdus crater is in a region with an unfavorable environment for solar wind to produce significant amounts of water on the surface.


"NASA missions like Lunar Prospector and the Lunar Crater Observation and Sensing Satellite and instruments like M3 have gathered crucial data that fundamentally changed our understanding of whether water exists on the surface of the moon," said S. Pete Worden, center director at NASA's Ames Research Center in Moffett Field, Calif. "Similarly, we hope that upcoming NASA missions such as the Lunar Atmosphere and Dust Environment Explorer, or LADEE, will change our understanding of the lunar sky."


The detection of internal water from orbit means scientists can begin to test some of the findings from sample studies in a broader context, including in regions that are far from where the Apollo sites are clustered on the near side of the moon. For many years, researchers believed that the rocks from the moon were bone-dry and any water detected in the Apollo samples had to be contamination from Earth.


"Now that we have detected water that is likely from the interior of the moon, we can start to compare this water with other characteristics of the lunar surface," said Klima. "This internal magmatic water also provides clues about the moon's volcanic processes and internal composition, which helps us address questions about how the moon formed, and how magmatic processes changed as it cooled."


The Moon Mineralogy Mapper was selected as a Mission of Opportunity through the NASA Discovery Program. NASA's Jet Propulsion Laboratory, Pasadena, Calif., designed and built the Moon Mineralogy Mapper and is home to its project manager, Mary White. JPL managed the program for NASA's Science Mission Directorate, Washington. Carle Pieters of Brown University, Providence, R.I., was the principal investigator. Joshua Cahill and David Lawrence of APL and Justin Hagerty of the U.S. Geological Survey's Astrogeology Science Center in Flagstaff, Ariz., co-authored the paper. The Chandrayaan-1 spacecraft was constructed, launched, and is operated by the Indian Space Research Organisation.


More information about Chandrayaan-1 visit: http://www.isro.org/Chandrayaan .

DC Agle 818-393-9011

Jet Propulsion Laboratory, Pasadena, Calif.

agle@jpl.nasa.gov


Dwayne Brown 202-358-1726

NASA Headquarters, Washington

dwayne.c.brown@nasa.gov


2013-262

NuSTAR Delivers the X-Ray Goods

NuSTAR Delivers the X-Ray Goods:

Artist's concept of NuSTAR in orbit.
Artist's concept of NuSTAR on orbit. NuSTAR has a 10-m (30') mast that deploys after launch to separate the optics modules (right) from the detectors in the focal plane (left). Image credit:
NASA/JPL-Caltech
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August 29, 2013

NASA's Nuclear Spectroscopic Telescope Array, or NuSTAR, is giving the wider astronomical community a first look at its unique X-ray images of the cosmos. The first batch of data from the black-hole hunting telescope is publicly available today, Aug. 29, via NASA's High Energy Astrophysics Science Archive Research Center, or HEASARC.


"We are pleased to present the world with NuSTAR's first look at the sky in high-energy X-rays with a true focusing telescope," said Fiona Harrison, the mission's principal investigator at the California Institute of Technology, Pasadena.


The images, taken from July to August 2012, shortly after the spacecraft launched, comprise an assortment of extreme objects, including black holes near and far. The more distant black holes are some of the most luminous objects in the universe, radiating X-rays as they ferociously consume surrounding gas. One type of black hole in the new batch of data is a blazar, which is an active, supermassive black hole pointing a jet toward Earth. Pairs of black holes called X-ray binaries, in which one partner feeds off the other, are also in the mix, along with the remnants of stellar blasts called supernovas.


The data set only contains complete observations. Data will be released at a later date for those targets still being observed.


"Astronomers can use these data to better understand the capabilities of NuSTAR and design future observing proposals. The first opportunity will be this fall, for joint observations with XMM-Newton," said Karl Forster of Caltech, who is leading the effort to package the data for the public.


The European Space Agency's XMM-Newton X-ray telescope, like NASA's Chandra X-ray Observatory, complements NuSTAR. While XMM-Newton and Chandra see lower-energy X-ray light, NuSTAR is the first telescope capable of focusing high-energy X-ray light, allowing for more detailed images than were possible before.


Astronomers can compare data sets from different missions using HEASARC, which gives them a broader understanding of an object of interest. NuSTAR's high-energy observations help scientists bridge a gap that existed previously in X-ray astronomy, and will lead to new revelations about the bizarre and energetic side of our universe.


Other NASA missions with data available via HEASARC include Chandra, Fermi, Swift, Cosmic Background Explorer (COBE), Wilkinson Microwave Anisotropy Probe (WMAP) and many more.


The HEASARC is a service of the Astrophysics Science Division at NASA's Goddard Space Flight Center in Greenbelt, Md., and the High Energy Astrophysics Division of the Smithsonian Astrophysics Observatory in Cambridge, Mass. HEASARC holdings include data obtained by NASA's high-energy astronomy missions observing in the extreme-ultraviolet, X-ray, and gamma-ray bands, as well as data from missions, balloons and ground-based facilities that have studied the relic cosmic microwave background. HEASARC is online at http://heasarc.gsfc.nasa.gov .


NuSTAR is a Small Explorer mission led by Caltech and managed by NASA's Jet Propulsion Laboratory, Pasadena, Calif., for NASA's Science Mission Directorate in Washington. The spacecraft was built by Orbital Sciences Corporation, Dulles, Va. Its instrument was built by a consortium including Caltech; JPL; the University of California, Berkeley; Columbia University, New York; NASA's Goddard Space Flight Center, Greenbelt, Md.; the Danish Technical University in Denmark; Lawrence Livermore National Laboratory, Livermore, Calif.; ATK Aerospace Systems, Goleta, Calif., and with support from the Italian Space Agency (ASI) Science Data Center.


NuSTAR's mission operations center is at UC Berkeley, with ASI providing its equatorial ground station located at Malindi, Kenya. The mission's outreach program is based at Sonoma State University, Rohnert Park, Calif. NASA's Explorer Program is managed by Goddard. JPL is managed by Caltech for NASA.


For more information, visit http://www.nasa.gov/nustar and http://www.nustar.caltech.edu/ .

Alan Buis 818-354-0474

Jet Propulsion Laboratory, Pasadena, Calif.

Alan.buis@jpl.nasa.gov


2013-264

NASA Study Eyes Soot's Role in 1800s Glacier Retreat

NASA Study Eyes Soot's Role in 1800s Glacier Retreat:

researchers and collaborators have combined historical records, ancient ice from cores in glaciers
NASA researchers and collaborators have combined historical records, ancient ice from cores in glaciers, modern air pollution studies and a model of glacier behavior to offer an explanation of why glaciers in the Alps started retreating in the late 19th century, despite cool temperatures and ample snowfall, which should have kept them growing. They find that soot from industrialization in Europe was deposited on the lower slopes of the glaciers, and that soot absorbed sunlight and accelerated melting. Although pollution sources today are not the same as in the 19th century, there is still enough pollution to make the air circulation patterns visible. This photo from summer 2012 looking south into the Bernese Alps shows how air pollution in the Alps tends to be confined to lower altitudes, concentrating the deposition of soot and dust on the lower slopes. At center left in the picture, a glacier can be seen extending from a high-altitude snow field, above the pollution layer, down into the valley where its lower reach is bathed in pollutants. Image credit: Peter Holy

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September 03, 2013

PASADENA, Calif. - A NASA-led team of scientists has uncovered strong evidence that soot from a rapidly industrializing Europe caused the abrupt retreat of mountain glaciers in the European Alps that began in the 1860s, a period often thought of as the end of the Little Ice Age.


The research, published Sept. 3 in the Proceedings of the National Academy of Sciences, may help resolve a longstanding scientific debate.


In the decades following the 1850s, Europe underwent an economic and atmospheric transformation spurred by industrialization. The use of coal to heat homes and power transportation and industry in Western Europe began in earnest, spewing huge quantities of black carbon and other dark particles into the atmosphere.


Black carbon is the strongest sunlight-absorbing atmospheric particle. When these particles settle on the snow blanketing glaciers, they darken the snow surface, speeding its melting and exposing the underlying glacier ice to sunlight and warmer spring and summer air earlier in the year. This diminishing of the snow cover earlier in each year causes the glacier ice to melt faster and retreat.


The Little Ice Age, loosely defined as a cooler period between the 14th and 19th centuries, was marked by an expansion of mountain glaciers and a drop in temperatures in Europe of nearly 1.8 degrees Fahrenheit (1 degree Celsius). But glacier records show that between 1860 and 1930, while temperatures continued to drop, large valley glaciers in the Alps abruptly retreated by an average of nearly 0.6 mile (1 kilometer) to lengths not seen in the previous few hundred years. Glaciologists and climatologists have struggled to reconcile this apparent conflict between climate and glacier records.


"Something was missing from the equation," said Thomas Painter, a snow and ice scientist at NASA's Jet Propulsion Laboratory in Pasadena, Calif., who led the study. "Before now, most glaciologists believed the end of the Little Ice Age came in the mid-1800s when these glaciers retreated, and that the retreat was due to a natural climatic shift, distinct from the carbon dioxide-induced warming that came later in the 20th century. This result suggests that human influence on glaciers extends back to well before the industrial temperature increases."


To help the scientists understand what was driving the glacier retreat, Painter and his colleagues turned to history. The researchers studied data from ice cores drilled from high up on several European mountain glaciers to determine how much black carbon was in the atmosphere and snow when the Alps glaciers began to retreat. Using the levels of carbon particles trapped in the ice core layers, and taking into consideration modern observations of how pollutants are distributed in the Alps, they were able to estimate how much black carbon was deposited on glacial surfaces at lower elevations, where levels of black carbon tend to be highest.


The team then ran computer models of glacier behavior, starting with recorded weather conditions and adding the impact of the lower-elevation pollution. When this impact was included, the simulated glacier mass loss and timing finally were consistent with the historic record of glacial retreat, despite the cooling temperatures at that time.


"We must now look more closely at other regions on Earth, such as the Himalaya, to study the present-day impacts of black carbon on glaciers in these regions," said Georg Kaser, a study co-author from the University of Innsbruck, Austria, and lead author of the Working Group I Cryosphere chapter of the Intergovernmental Panel on Climate Change's upcoming Fifth Assessment Report.


"This study uncovers likely human fingerprints on our changing environment," said co-author Waleed Abdalati, director of the Cooperative Institute for Research and Environmental Sciences (CIRES) at the University of Colorado Boulder. "It's a reminder that the actions we take have far-reaching impacts on the environment in which we live."


CIRES is a joint institute of the university and the National Oceanic and Atmospheric Administration. Other institutions participating in the study include the University of Michigan - Ann Arbor and the University of California, Davis. The California Institute of Technology in Pasadena manages JPL for NASA.


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


Additional media contacts for this story: Katy Human, CIRES, 303-735-0196, Kathleen.human@colorado.edu ; Nicole Casal Moore, University of Michigan, 734-647-7087, ncmoore@umich.edu ; Stefan Hohenwarter, University of Innsbruck, 011-43-512-50732023, stefan.hohenwarter@uibk.ac.at ; Kat Kerlin, UC Davis, 530-752-7704, kekerlin@ucdavis.edu .

Alan Buis 818-354-0474

Jet Propulsion Laboratory, Pasadena, Calif.

Alan.buis@jpl.nasa.gov


Steve Cole 202-358-0918

NASA Headquarters, Washington

Stephen.e.cole@nasa.gov


2013-267