Monday, July 21, 2014

Stormy Stars? NASA's Spitzer Probes Weather on Brown Dwarfs

Stormy Stars? NASA's Spitzer Probes Weather on Brown Dwarfs:

This Just In: Storms Expected on Brown Dwarfs
This artist's concept shows what the weather might look like on cool star-like bodies known as brown dwarfs. These giant balls of gas start out life like stars, but lack the mass to sustain nuclear fusion at their cores, and instead, fade and cool with time. Image credit: NASA/JPL-Caltech/University of Western Ontario/Stony Brook University
› Full image and caption


January 07, 2014

Swirling, stormy clouds may be ever-present on cool celestial orbs called brown dwarfs. New observations from NASA's Spitzer Space Telescope suggest that most brown dwarfs are roiling with one or more planet-size storms akin to Jupiter's "Great Red Spot."

"As the brown dwarfs spin on their axis, the alternation of what we think are cloud-free and cloudy regions produces a periodic brightness variation that we can observe," said Stanimir Metchev of Western University, Ontario, Canada. "These are signs of patchiness in the cloud cover."

Metchev is principal investigator of the brown dwarf research. The results were presented at a news conference today at the 223rd annual meeting of the American Astronomical Society in Washington by Metchev's colleague, Aren Heinze, of Stony Brook University, New York. 

Brown dwarfs form as stars do, but lack the mass to fuse atoms continually and blossom into full-fledged stars. They are, in some ways, the massive kin to Jupiter.

Scientists think that the cloudy regions on brown dwarfs take the form of torrential storms, accompanied by winds and, possibly, lightning more violent than that at Jupiter or any other planet in our solar system. However, the brown dwarfs studied so far are too hot for water rain; instead, astronomers believe the rain in these storms, like the clouds themselves, is made of hot sand, molten iron or salts. 

In a Spitzer program named "Weather on Other Worlds," astronomers used the infrared space telescope to watch 44 brown dwarfs as they rotated on their axis for up to 20 hours. Previous results had suggested that some brown dwarfs have turbulent weather, so the scientists had expected to see a small fraction vary in brightness over time. However, to their surprise, half of the brown dwarfs showed the variations. When you take into account that half of the objects would be oriented in such a way that their storms would be either hidden or always in view and unchanging, the results indicate that most, if not all, brown dwarfs are racked by storms.

"We needed Spitzer to do this," said Metchev. "Spitzer is in space, above the thermal glow of the Earth's atmosphere, and it has the sensitivity required to see variations in the brown dwarfs' brightness."

The results led to another surprise as well. Some of the brown dwarfs rotated much more slowly than any previously measured, a finding that could not have been possible without Spitzer's long, uninterrupted observations from space. Astronomers had thought that brown dwarfs sped up to very fast rotations when they formed and contracted, and that this rotation didn't wind down with age.

"We don't yet know why these particular brown dwarfs spin so slowly, but several interesting possibilities exist," said Heinze.  "A brown dwarf that rotates slowly may have formed in an unusual way -- or it may even have been slowed down by the gravity of a yet-undiscovered planet in a close orbit around it."

The work may lead to a better understanding of not just brown dwarfs but their "little brothers": the gas-giant planets. Researchers say that studying the weather on brown dwarfs will open new windows onto weather on planets outside our solar system, which are harder to study under the glare of their stars. Brown dwarfs are weather laboratories for planets, and, according to the new results, those laboratories are everywhere.

Other researchers on the team include: Daniel Apai and Davin Flateau of the University of Arizona, Tucson; Mark Marley of NASA Ames Research Center, Moffett Field; Jacqueline Radigan of the Space Telescope Science Institute, Baltimore, Md.; Etienne Artigau of Universite de Montreal, Canada; Adam Burgasser of University of California San Diego; Peter Plavchan of NASA's Exoplanet Science Institute at the California Institute of Technology, Pasadena; and Bertrand Goldman of Max-Planck Institute for Astronomy, Germany.

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 the California Institute of Technology in Pasadena. Spacecraft operations are based at Lockheed Martin Space Systems Company, Littleton, Colorado. 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 .

Whitney Clavin 818-354-4673

Jet Propulsion Laboratory, Pasadena, Calif.

whitney.clavin@jpl.nasa.gov

2014-005
Posted by Nelio Inacio at 4:55 PM 0 comments

Recently Reactivated NASA Spacecraft Spots Its First New Asteroid

Recently Reactivated NASA Spacecraft Spots Its First New Asteroid:

NEOWISE's New Find
The six red dots in this composite picture indicate the location of the first new near-Earth asteroid seen by NASA's Near-Earth Object Wide-field Infrared Survey Explorer (NEOWISE) since the spacecraft came out of hibernation in December 2013. The asteroid, called 2013 YP139, is the first of hundreds of space-rock discoveries expected during its renewed mission. The inset shows a zoomed-in view of one of the detections of 2013 YP139. Image credit: NASA/JPL-Caltech
› Full image and caption


January 07, 2014

NASA's Near-Earth Object Wide-field Infrared Survey Explorer (NEOWISE) spacecraft has spotted a never-before-seen asteroid -- its first such discovery since coming out of hibernation last year.

NEOWISE originally was called the Wide-field Infrared Survey Explorer (WISE), which had made the most comprehensive survey to date of asteroids and comets. The spacecraft was shut down in 2011 after its primary mission was completed. But in September 2013, it was reactivated, renamed and given a new mission, which is to assist NASA's efforts to identify the population of potentially hazardous near-Earth objects (NEOs). NEOWISE also can assist in characterizing previously detected asteroids that could be considered potential targets for future exploration missions.

NEOWISE's first discovery of its renewed mission came on Dec. 29 -- a near-Earth asteroid designated 2013 YP139. The mission's sophisticated software picked out the moving object against a background of stationary stars. As NEOWISE circled Earth scanning the sky, it observed the asteroid several times over half a day before the object moved beyond its view. Researchers at the University of Arizona used the Spacewatch telescope at the Kitt Peak National Observatory southwest of Tucson to confirm the discovery. Peter Birtwhistle, an amateur astronomer at the Great Shefford Observatory in West Berkshire, England, also contributed follow-up observations. NASA expects 2013 YP139 will be the first of hundreds of asteroid discoveries for NEOWISE.

"We are delighted to get back to finding and characterizing asteroids and comets, especially those that come into Earth's neighborhood," said Amy Mainzer, the mission's principal investigator from NASA's Jet Propulsion Laboratory in Pasadena, Calif. "With our infrared sensors that detect heat, we can learn about their sizes and reflectiveness."

2013 YP139 is about 27 million miles (43 million kilometers) from Earth. Based on its infrared brightness, scientists estimate it to be roughly 0.4 miles (650 meters) in diameter and extremely dark, like a piece of coal. The asteroid circles the sun in an elliptical orbit tilted to the plane of our solar system and is classified as potentially hazardous. It is possible for its orbit to bring it as close as 300,000 miles from Earth, a little more than the distance to the moon. However, it will not come that close within the next century.

WISE discovered more than 34,000 asteroids and characterized 158,000 throughout the solar system during its prime mission in 2010 and early 2011. Its reactivation in September followed 31 months in hibernation.

NEOWISE will continue to detect asteroids and comets. The observations will be automatically sent to the clearinghouse for solar system bodies, the Minor Planet Center in Cambridge, Mass., for comparison against the known catalog of solar system objects and to determine orbit if the object is not known. A community of professional and amateur astronomers will provide follow-up observations, establishing firm orbits for the previously unseen objects.

Infrared sensors, similar to the cameras on NEOWISE, are a powerful tool for discovering, cataloging and understanding the asteroid population. Some of the objects about which NEOWISE will be collecting data could become candidates for NASA's announced asteroid initiative, which will be the first mission to identify, capture and relocate an asteroid for astronauts to explore. The initiative represents an unprecedented technological feat that will lead to new scientific discoveries and technological capabilities that will help protect our home planet and achieve the goal of sending humans to an asteroid by 2025.

JPL manages the project for NASA's Science Mission Directorate in Washington. 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.

An image of asteroid 2013 YP139, taken by NEOWISE, is available at http://go.nasa.gov/1cNF9T7 .

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

DC Agle/Guy Webster 818-393-9011/354-6278

Jet Propulsion Laboratory, Pasadena, Calif.

agle@jpl.nasa.gov / guy.webster@jpl.nasa.gov


Dwayne Brown 202-358-1726

NASA Headquarters, Washington

dwayne.c.brown@nasa.gov

2013-006
Posted by Nelio Inacio at 4:54 PM 0 comments

NASA's Hubble and Spitzer Team up to Probe Faraway Galaxies

NASA's Hubble and Spitzer Team up to Probe Faraway Galaxies:

Hubble Frontier Field Abell 2744
This long-exposure image from NASA's Hubble Space Telescope of massive galaxy cluster Abell 2744 is the deepest ever made of any cluster of galaxies. It shows some of the faintest and youngest galaxies ever detected in space. Image credit: NASA/ESA/STScI
› Full image and caption


January 07, 2014

NASA's Hubble and Spitzer Space Telescopes are providing a new perspective on the remote universe, including new views of young and distant galaxies bursting with stars. Scientists described the findings Tuesday in a news conference sponsored by the American Astronomical Society.

The discoveries include four unusually bright galaxies as they appeared 13 billion years ago and the deepest image ever obtained of a galaxy cluster.

The ultra-bright, young galaxies, discovered using data from Hubble and Spitzer, are bursting with star-formation activity, which accounts for their brilliance. The brightest one is forming stars approximately 50 times faster than our Milky Way galaxy does today. These fledgling galaxies are only one-twentieth the size of the Milky Way, but they probably contain about 1 billion stars crammed together.

Although Hubble has previously identified galaxies at this early epoch, astronomers were surprised to find objects that are about 10 to 20 times more luminous than anything seen previously.

"These just stuck out like a sore thumb because they are far brighter than we anticipated," explained Garth Illingworth of the University of California at Santa Cruz. "There are strange things happening regardless of what these sources are. We're suddenly seeing luminous, massive galaxies quickly build up at such an early time. This was quite unexpected."

The galaxies were first detected with Hubble. Its sharp images are crucial to finding such distant galaxies and enabled the astronomers to measure their star-formation rates and sizes. Using Spitzer, the astronomers were able to estimate the stellar masses by measuring the total stellar luminosity of the galaxies.

"This is the first time scientists were able to measure an object's mass at such a huge distance," said Pascal Oesch of Yale University in New Haven, Conn. "It's a fabulous demonstration of the synergy between Hubble and Spitzer."

The result bodes well for NASA's James Webb Space Telescope, currently in development. Scientists anticipate using Webb to look even further back in time to find young, growing galaxies as they existed only a few hundred million years after the universe began in the big bang.

An unprecedented long-distance view of the universe comes from an ambitious collaborative project with Hubble called The Frontier Fields. It is the longest and deepest exposure obtained to date of a cluster of galaxies, and shows some of the faintest and youngest galaxies ever detected. The image contains several hundred galaxies as they looked 3.5 billion years ago.

Appearing in the foreground of the image is Abell 2744, a massive galaxy cluster located in the constellation Sculptor. The immense gravity in Abell 2744 is being used as a lens to warp space and brighten and magnify images of more distant background galaxies. The more distant galaxies appear as they did longer than 12 billion years ago, not long after the big bang.

The Hubble exposure reveals almost 3,000 of these background galaxies interleaved with images of hundreds of foreground galaxies in the cluster. Their images not only appear brighter, but also smeared, stretched and duplicated across the field. Because of the gravitational lensing phenomenon, the background galaxies are magnified to appear as much as 10 to 20 times larger than they would normally appear. Furthermore, the faintest of these highly magnified objects is 10 to 20 times fainter than any galaxy observed previously. Without the boost from gravitational lensing, the many background galaxies would be invisible.

The Hubble exposure will be combined with images from Spitzer and NASA's Chandra X-ray Observatory to provide new insight into the origin and evolution of galaxies and their accompanying black holes.

For images and more information about the ultra-bright young galaxies, visit: http://hubblesite.org/news/2014/05 . To see more images and information about The Frontier Fields campaign, visit: http://hubblesite.org/news/2014/01 .

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 the California Institute of Technology in Pasadena. Spacecraft operations are based at Lockheed Martin Space Systems Company, Littleton, Colorado. 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 .

Whitney Clavin 818-648-9734

Jet Propulsion Laboratory, Pasadena, Calif.

whitney.clavin@jpl.nasa.gov


Ann Jenkins / Ray Villard 410-338-4488 / 410-338-4514

Space Telescope Science Institute, Baltimore

jenkins@stsci.edu / villard@stsci.edu

2014-007
Posted by Nelio Inacio at 4:53 PM 0 comments

Powerful Planet Finder Turns Its Eye to the Sky

Powerful Planet Finder Turns Its Eye to the Sky:

Gemini Planet Imager¹s First Light Image of Beta Pictoris b
This image taken by the Gemini Planet Imager (GPI) shows a planet orbiting the star Beta Pictoris. In addition to the image, the GPI obtains spectral information from every pixel element in the field of view, allowing scientists to study the planet in great detail. Image credit: Gemini/Christian Marois, NRC Canada.

› Full image and caption


January 07, 2014

After nearly a decade of development, construction and testing, the world's most advanced instrument for directly imaging and analyzing planets around other stars is pointing skyward and collecting light from distant worlds.

The instrument, called the Gemini Planet Imager (GPI), was designed, built, and optimized for imaging giant planets next to bright stars, in addition to studying dusty disks around young stars. It is the most advanced instrument of its kind to be deployed on one of the world's biggest telescopes - the 26-foot (8-meter) Gemini South telescope in Chile.

Imaging a planet next to a star is a tricky task. The planet is much fainter than its star, and also appears very close. These challenges make the act of separating the planet's light from the glare of the star difficult. NASA's Jet Propulsion Laboratory in Pasadena, Calif., contributed to the project by designing and building an ultra-precise infrared sensor to measure small distortions in starlight that might mask a planet.

"Our tasks were two-fold," said Kent Wallace, JPL's subsystem technical lead for the project. "First, keep the star centered on the instrument so that its glare is blocked as much as possible. Second, ensure the instrument itself is stable during the very long exposures required to image faint companions."

GPI detects infrared, or heat, radiation from young Jupiter-like planets in wide orbits around other stars. Those are equivalent to the giant planets in our own solar system not long after their formation. Every planet GPI sees can be studied in detail, revealing components of their atmospheres.

Although GPI was designed to look at distant planets, it can also observe objects in our solar system. Test images of Jupiter's moon Europa, for example, can allow scientists to map changes in the satellite's surface composition. The images were released today at the 223rd meeting of the American Astronomical Society in Washington.

Read the full news release from Gemini Observatory at http://www.gemini.edu/node/12113 .

Whitney Clavin 818-354-4673

Jet Propulsion Laboratory, Pasadena, Calif.

whitney.clavin@jpl.nasa.gov

2014-008
Posted by Nelio Inacio at 4:52 PM 0 comments

Sunday, July 20, 2014

Dead Star and Distant Black Holes Dazzle in X-Rays

Dead Star and Distant Black Holes Dazzle in X-Rays:

High-Energy X-ray View of 'Hand of God'
Can you see the shape of a hand in this new X-ray image? The hand might look like an X-ray from the doctor's office, but it is actually a cloud of material ejected from a star that exploded. NASA's Nuclear Spectroscopic Telescope Array, or NuSTAR, has imaged the structure in high-energy X-rays for the first time, shown in blue. Lower-energy X-ray light previously detected by NASA's Chandra X-ray Observatory is shown in green and red. Image credit: NASA/JPL-Caltech/McGill
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January 09, 2014

Two new views from NASA's Nuclear Spectroscopic Telescope Array, or NuSTAR, showcase the telescope's talent for spying objects near and far. One image shows the energized remains of a dead star, a structure nicknamed the "Hand of God" after its resemblance to a hand. Another image shows distant black holes buried in blankets of dust.

"NuSTAR's unique viewpoint, in seeing the highest-energy X-rays, is showing us well-studied objects and regions in a whole new light," said Fiona Harrison, the mission's principal investigator at the California Institute of Technology in Pasadena, Calif.

NuSTAR launched into space June 13, 2012, on a mission to explore the high-energy X-ray universe. It is observing black holes, dead and exploded stars and other extreme objects in our own Milky Way galaxy and beyond.

The new "Hand of God" image shows a nebula 17,000 light-years away, powered by a dead, spinning star called PSR B1509-58, or B1509 for short. The dead star, called a pulsar, is the leftover core of a star that exploded in a supernova. The pulsar is only about 19 kilometers (12 miles) in diameter but packs a big punch: it is spinning around nearly seven times every second, spewing particles into material that was upheaved during the star's violent death. These particles are interacting with magnetic fields around the ejected material, causing it to glow with X-rays. The result is a cloud that, in previous images, looked like an open hand.

One of the big mysteries of this object, called a pulsar wind nebula, is whether the pulsar's particles are interacting with the material in a specific way to make it appear as a hand, or if the material is in fact shaped like a hand.

"We don't know if the hand shape is an optical illusion," said Hongjun An of McGill University, Montreal, Canada. "With NuSTAR, the hand looks more like a fist, which is giving us some clues."

The second image from NuSTAR shows active, supermassive black holes between three and 10 billion light-years away in a well-studied patch of sky called the COSMOS field (for Cosmic Evolution Survey). Each dot is a voracious black hole at the heart of a galaxy, actively feeding off a surrounding disk of material. NASA's Chandra X-ray Observatory and other telescopes have identified many of the black holes in this field, but some are so heavily obscured in gas and dust that NuSTAR's higher-energy X-ray observations are needed to characterize and understand them. Astronomers hope to use NuSTAR to provide new demographics on the numbers, types and distances to black holes that populate our universe.

"This is a hot topic in astronomy," said Francesca Civano of Yale University, New Haven, Conn. "We want to understand how black holes grew in the past and the degree to which they are obscured." The ongoing research will help explain how black holes and galaxies grow and interact with each other.

NuSTAR is a Small Explorer mission led by the California Institute of Technology in Pasadena and managed by NASA's Jet Propulsion Laboratory, also in Pasadena, 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, N.Y.; 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, Rome, Italy.

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/ .

Whitney Clavin 818-354-4673
Jet Propulsion Laboratory, Pasadena, Calif.
whitney.clavin@jpl.nasa.gov

2014-010
Posted by Nelio Inacio at 2:02 PM 0 comments

Rosetta: To Chase a Comet

Rosetta: To Chase a Comet:

An artist's view of Rosetta, the European Space Agency's cometary probe with NASA contributions.
An artist's view of Rosetta, the European Space Agency's cometary probe with NASA contributions. Image credit: ESA
› Full image and caption


January 17, 2014

Update: January 21


The Rosetta spacecraft "woke up" after a record 957 days of hibernation. The first communication from the spacecraft arrived at the European Space Operations Center in Darmstadt, Germany, at 7:18 p.m. local time (1:18 p.m. EST / 10:18 a.m. PST). The signal was received by ground stations at the Goldstone, Calif., and Canberra, Australia, complexes of NASA's Deep Space Network.

Rosetta, heading toward comet 67P/Churyumov-Gerasimenko, is an international mission spearheaded by the European Space Agency with support and instruments provided by NASA.


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Comets are among the most beautiful and least understood nomads of the night sky. To date, half a dozen of these most heavenly of heavenly bodies have been visited by spacecraft in an attempt to unlock their secrets. All these missions have had one thing in common: the high-speed flyby. Like two ships passing in the night (or one ship and one icy dirtball), they screamed past each other at hyper velocity -- providing valuable insight, but fleeting glimpses, into the life of a comet. That is, until Rosetta.

NASA is participating in the European Space Agency's Rosetta mission, whose goal is to observe one such space-bound icy dirt ball from up close -- for months on end. The spacecraft, festooned with 25 instruments between its lander and orbiter (including three from NASA), is programmed to "wake up" from hibernation on Jan. 20. After a check-out period, it will monitor comet 67P/Churyumov-Gerasimenko as it makes its nosedive into, and then climb out of, the inner solar system. Over 16 months, during which old 67P is expected to transform from a small, frozen world into a roiling mass of ice and dust, complete with surface eruptions, mini-earthquakes, basketball-sized, fluffy ice particles and spewing jets of carbon dioxide and cyanide.

"We are going to be in the cometary catbird seat on this one," said Claudia Alexander, project scientist for U.S. Rosetta from NASA's Jet Propulsion Laboratory in Pasadena, Calif. "To have an extended presence in the neighborhood of a comet as it goes through so many changes should change our perspective on what it is to be a comet."

Since work began on Rosetta back in 1993, scientists and engineers from all over Europe and the United States have been combining their talents to build an orbiter and a lander for this unique expedition. NASA's contribution includes three of the orbiter's instruments (an ultraviolet spectrometer called Alice; the Microwave Instrument for Rosetta Orbiter; and the Ion and Electron Sensor. NASA is also providing part of the electronics package for an instrument called the Double Focusing Mass Spectrometer, which is part of the Swiss-built Rosetta Orbiter Spectrometer for Ion and Neutral Analysis instrument. NASA is also providing U.S. science investigators for selected non-U.S. instruments and is involved to a greater or lesser degree in seven of the mission's 25 instruments. NASA's Deep Space Network provides support for ESA's Ground Station Network for spacecraft tracking and navigation.

"All the instruments aboard Rosetta and the Philae lander are designed to work synergistically," said Sam Gulkis of JPL, the principal investigator for the Microwave Instrument for Rosetta Orbiter. "They will all work together to create the most complete picture of a comet to date, telling us how the comet works, what it is made of, and what it can tell us about the origins of the solar system."

The three NASA-supplied instruments are part of the orbiter's scientific payload. Rosetta's Microwave Instrument for Rosetta Orbiter specializes in the thermal properties. The instrument combines a spectrometer and radiometer, so it can sense temperature and identify chemicals located on or near the comet's surface, and even in the dust and ices jetting out from it. The instrument will also see the gaseous activity through the dusty cloud of material. Rosetta scientists will use it to determine how different materials in the comet change from ice to gas, and to observe how much it changes in temperature as it approaches the sun.

Like the Microwave for Rosetta Orbiter, the Alice instrument contains a spectrometer. But Alice looks at the ultraviolet portion of the spectrum. Alice will analyze gases in the coma and tail and measure the comet's production rates of water and carbon monoxide and dioxide. It will provide information on the surface composition of the nucleus, and make a potentially key measurement of argon, which will be a big clue about what the temperature was in the primordial solar system when the comet's nucleus originally formed (more than 4.6 billion years ago).

The Rosetta orbiter's Ion and Electron Sensor is part of a suite of five instruments to characterize the plasma environment of the comet -- in particular, its coma, which develops when the comet approaches the sun. The sun's outer atmosphere, the solar wind, interacts with the gas flowing out from the comet, and the instrument will measure the charged particles it comes in contact with as the orbiter approaches the comet's nucleus.

All three instruments are slated to begin science collection by early summer. Along with the pure science they will provide, their data are expected to help Rosetta project management determine where to attempt to land their Philae lander on the comet in November.

"It feels good to be part of a team that is on the cusp of making some space exploration history," said Art Chmielewski, NASA's project manager for US Rosetta, based at JPL. "There are so many exciting elements and big milestones coming up in this mission that it feels like I should buy a ticket and a big box of popcorn. Rosetta is going to be a remarkable ride."

Rosetta is a mission of the European Space Agency, Paris, with contributions from its member states and NASA. Rosetta's Philae lander is provided by a consortium led by the German Aerospace Center, the Max Planck Institute for Solar System Research, the French National Space Agency and the Italian Space Agency. JPL manages the U.S. contribution of the Rosetta mission for NASA's Science Mission Directorate in Washington. The Microwave Instrument for the Rosetta Orbiter was built at JPL and JPL is home to its principal investigator, Samuel Gulkis. The Southwest Research Institute, San Antonio, developed the Rosetta orbiter's Ion and Electron Sensor (IES) and is home to its principal investigator, James Burch. The Southwest Research Institute, Boulder, Colo., developed the Alice instrument and is home to its principal investigator, Alan Stern.

More information about Rosetta is available online at: http://www.esa.int/rosetta and http://rosetta.jpl.nasa.gov .

DC Agle/Jia-Rui Cook 818-393-9011/818-354-0850

Jet Propulsion Laboratory, Pasadena, Calif.

agle@jpl.nasa.gov / jccook@jpl.nasa.gov

Dwayne Brown 202-358-1726

Headquarters, Washington

dwayne.c.brown@nasa.gov


Markus Bauer 31-71-565-6799

European Space Agency, Noordwijk, The Netherland

markus.bauer@esa.int


2014-015
Posted by Nelio Inacio at 2:01 PM 0 comments

NASA Set for a Big Year in Earth Science

NASA Set for a Big Year in Earth Science:

Artist's rendering of NASA's Orbiting Carbon Observatory (OCO)-2, one of five new NASA Earth science missions set to launch in 2014, and one of three managed by JPL
Artist's rendering of NASA's Orbiting Carbon Observatory (OCO)-2, one of five new NASA Earth science missions set to launch in 2014, and one of three managed by JPL. Image credit: NASA-JPL/Caltech
› Full image and caption


January 22, 2014

For the first time in more than a decade, five NASA Earth science missions will be launched into space in the same year, opening new and improved remote eyes to monitor our changing planet.


The five launches, including two to the International Space Station (ISS), are part of an active year for NASA Earth science researchers, who also will conduct airborne campaigns to the poles and hurricanes, develop advanced sensor technologies, and use satellite data and analytical tools to improve natural hazard and climate change preparedness.


NASA satellites, aircraft and research help scientists and policymakers find answers to critical challenges facing our planet, including climate change, sea level rise, decreasing availability of fresh water and extreme weather events.


"As NASA prepares for future missions to an asteroid and Mars, we're focused on Earth right now," said NASA Administrator Charles Bolden. "With five new missions set to launch in 2014, this really is shaping up to be the year of the Earth, and this focus on our home planet will make a significant difference in people's lives around the world."


The first NASA Earth science mission of 2014 is the Global Precipitation Measurement (GPM) Core Observatory, a joint satellite project with the Japan Aerospace Exploration Agency (JAXA). The mission inaugurates an unprecedented international satellite constellation that will produce the first nearly global observations of rainfall and snowfall. This new information will help answer questions about our planet's life-sustaining water cycle, and improve water resource management and weather forecasting.


The GPM Core Observatory is scheduled to launch on Feb. 27 from JAXA's Tanegashima Space Center on a Japanese H-IIA rocket. The spacecraft was built at NASA's Goddard Space Flight Center, Greenbelt, Md.


In July, NASA will launch a mission to advance our understanding of carbon dioxide's role in climate change. The Orbiting Carbon Observatory (OCO)-2, a replacement for a mission lost after a launch vehicle failure in 2009, will make precise, global measurements of carbon dioxide, the greenhouse gas that is the largest human-generated contributor to global warming. OCO-2 observations will be used to improve understanding of the natural and human-induced sources of carbon dioxide and how these emissions cycle through Earth's oceans, land and atmosphere.


OCO-2, managed by NASA's Jet Propulsion Laboratory in Pasadena, Calif., will launch from Vandenberg Air Force Base, Calif., on a Delta II rocket.


With the November launch of NASA's Soil Moisture Active Passive (SMAP) mission, NASA will track Earth's water into one of its last hiding places: the soil. SMAP will map Earth's soil moisture and provide precise indications of the soil's freeze-thaw state, to improve understanding of the cycling of water, energy and carbon. High-resolution global maps of soil moisture produced from SMAP data will inform water resource management decisions on water availability around our planet. SMAP data also will aid in predictions of plant growth and agricultural productivity, weather and climate forecasts, and monitoring floods and droughts.


SMAP, a JPL-managed mission, will launch from Vandenberg onboard a Delta II rocket.


"On our home planet Earth, water is an essential requirement for life and for most human activities. We must understand the details of how water moves within and between the atmosphere, the oceans and the land if we are to predict changes to our climate and the availability of water resources," said Michael Freilich, director of NASA's Earth Science Division in Washington. "Coupled with data from other ongoing NASA missions that measure sea-surface salinity and that detect changes in underground aquifer levels, with GPM and SMAP we will have unprecedented measurements of our planet's vital water cycle."


Two Earth science missions will be sent to the International Space Station this year to measure ocean winds, clouds and aerosols, marking NASA's first use of the orbiting laboratory as a 24/7 Earth-observing platform. The new instruments are the first of a series that will observe Earth routinely from the orbiting laboratory.


The space station has served as a unique platform advancing scientific research and technological discovery for more than 13 years. Its mid-inclination orbit allows for observations at all local times over nearly 85 percent of Earth's surface. NASA plans to launch five Earth-observing instruments to the ISS through 2017. These missions are developed and operated jointly by the International Space Station Program and the Earth Science Division.


ISS-RapidScat, managed by JPL and scheduled to launch to the station June 6, will extend the data record of ocean winds around the globe. These data are a key factor in climate research, weather and marine forecasting, and tracking of storms and hurricanes. Using inherited, repurposed hardware, ISS-RapidScat will provide high-value science at a fraction of the typical cost of developing a free-flying satellite. ISS-Rapidscat will fly to the station aboard a SpaceX Falcon 9 rocket and Dragon cargo spacecraft from Cape Canaveral Air Force Station, Fla., on a commercial resupply flight for the ISS.


The new Cloud-Aerosol Transport System (CATS) is a technology demonstration mission using three-wavelength lasers to extend satellite observations of small particles in the atmosphere from volcanoes, air pollution, dust and smoke. These aerosol particles pose human health risks at ground level and influence global climate through their impact on cloud cover and solar radiation in Earth's atmosphere. CATS is scheduled to launch Sept. 12 on another SpaceX ISS commercial resupply flight from Cape Canaveral Air Force Station.


"With these two instruments launching to the space station, ISS will come into its own as an important platform for studying the Earth system and global change," said Julie Robinson, space station chief scientist at NASA's Johnson Space Center in Houston. "This is just the beginning of the space station becoming a part of the global Earth-observing network."


NASA also uses a wide array of research aircraft equipped with sophisticated sensors to advance Earth science research. This year, NASA is sponsoring 12 flight campaigns that will study the polar ice sheets, urban air pollution, hurricanes, ecosystem health and more over the United States, Central and South America, Antarctica and the Arctic Circle.


Putting satellite data to work meeting local and regional needs around the world is another part of NASA's Earth science mission. In 2014, projects sponsored by the NASA Applied Sciences Program will tackle ecosystem issues in the Gulf of Mexico, water scarcity in the U.S. Southwest, and flood management in the Mekong River delta.


NASA continues to push the boundaries of current technologies to find new ways to see our complex planet in more detail and with greater accuracy. This year, NASA's Earth Science Technology Office will test new sensors to improve measurements of water levels in lakes and reservoirs, carbon dioxide, terrestrial ecosystems, and natural hazards such as earthquakes and tsunamis.


NASA monitors Earth's vital signs from land, air and space with a fleet of satellites and ambitious airborne and ground-based observation campaigns. NASA develops new ways to observe and study Earth's interconnected natural systems with long-term data records and computer analysis tools to better see how our planet is changing. The agency shares this unique knowledge with the global community and works with institutions in the United States and around the world that contribute to understanding and protecting our home planet.


For more information about NASA's Earth science activities in 2014, visit: http://www.nasa.gov/earthrightnow .


For information on the latest NASA Earth science findings, visit: http://www.nasa.gov/earth .

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


Susan Anderson 281-483-8630

Johnson Space Center, Houston

susan.h.anderson@nasa.gov


Rani Gran 301-286-2483

Goddard Space Flight Center, Greenbelt, Md.

rani.c.gran@nasa.gov


2014-019
Posted by Nelio Inacio at 2:00 PM 0 comments

Herschel Telescope Detects Water on Dwarf Planet

Herschel Telescope Detects Water on Dwarf Planet:

Artist's concept of Ceres
Dwarf planet Ceres is located in the main asteroid belt, between the orbits of Mars and Jupiter, as illustrated in this artist's conception.
› Full image and caption


January 22, 2014

Scientists using the Herschel space observatory have made the first definitive detection of water vapor on the largest and roundest object in the asteroid belt, Ceres.


Plumes of water vapor are thought to shoot up periodically from Ceres when portions of its icy surface warm slightly. Ceres is classified as a dwarf planet, a solar system body bigger than an asteroid and smaller than a planet.


Herschel is a European Space Agency (ESA) mission with important NASA contributions.


"This is the first time water vapor has been unequivocally detected on Ceres or any other object in the asteroid belt and provides proof that Ceres has an icy surface and an atmosphere," said Michael Küppers of ESA in Spain, lead author of a paper in the journal Nature.


The results come at the right time for NASA's Dawn mission, which is on its way to Ceres now after spending more than a year orbiting the large asteroid Vesta. Dawn is scheduled to arrive at Ceres in the spring of 2015, where it will take the closest look ever at its surface.


"We've got a spacecraft on the way to Ceres, so we don't have to wait long before getting more context on this intriguing result, right from the source itself," said Carol Raymond, the deputy principal investigator for Dawn at NASA's Jet Propulsion Laboratory in Pasadena, Calif. "Dawn will map the geology and chemistry of the surface in high resolution, revealing the processes that drive the outgassing activity."


For the last century, Ceres was known as the largest asteroid in our solar system. But in 2006, the International Astronomical Union, the governing organization responsible for naming planetary objects, reclassified Ceres as a dwarf planet because of its large size. It is roughly 590 miles (950 kilometers) in diameter. When it first was spotted in 1801, astronomers thought it was a planet orbiting between Mars and Jupiter. Later, other cosmic bodies with similar orbits were found, marking the discovery of our solar system's main belt of asteroids.


Scientists believe Ceres contains rock in its interior with a thick mantle of ice that, if melted, would amount to more fresh water than is present on all of Earth. The materials making up Ceres likely date from the first few million years of our solar system's existence and accumulated before the planets formed.


Until now, ice had been theorized to exist on Ceres but had not been detected conclusively. It took Herschel's far-infrared vision to see, finally, a clear spectral signature of the water vapor. But Herschel did not see water vapor every time it looked. While the telescope spied water vapor four different times, on one occasion there was no signature.


Here is what scientists think is happening: when Ceres swings through the part of its orbit that is closer to the sun, a portion of its icy surface becomes warm enough to cause water vapor to escape in plumes at a rate of about 6 kilograms (13 pounds) per second. When Ceres is in the colder part of its orbit, no water escapes.


The strength of the signal also varied over hours, weeks and months, because of the water vapor plumes rotating in and out of Herschel's views as the object spun on its axis. This enabled the scientists to localize the source of water to two darker spots on the surface of Ceres, previously seen by NASA's Hubble Space Telescope and ground-based telescopes. The dark spots might be more likely to outgas because dark material warms faster than light material. When the Dawn spacecraft arrives at Ceres, it will be able to investigate these features.


The results are somewhat unexpected because comets, the icier cousins of asteroids, are known typically to sprout jets and plumes, while objects in the asteroid belt are not.


"The lines are becoming more and more blurred between comets and asteroids," said Seungwon Lee of JPL, who helped with the water vapor models along with Paul von Allmen, also of JPL. "We knew before about main belt asteroids that show comet-like activity, but this is the first detection of water vapor in an asteroid-like object."


The research is part of the Measurements of 11 Asteroids and Comets Using Herschel (MACH-11) program, which used Herschel to look at small bodies that have been or will be visited by spacecraft, including the targets of NASA's previous Deep Impact mission and upcoming Origins Spectral Interpretation Resource Identification Security Regolith Explorer (OSIRIS-Rex). Laurence O' Rourke of the European Space Agency is the principal investigator of the MACH-11 program.


Herschel is a European Space Agency mission, with science instruments provided by consortia of European institutes and with important participation by NASA. While the observatory stopped making science observations in April 2013, after running out of liquid coolant, as expected, scientists continue to analyze its data. NASA's Herschel Project Office is based at JPL. JPL contributed mission-enabling technology for two of Herschel's three science instruments. The NASA Herschel Science Center, part of the Infrared Processing and Analysis Center at the California Institute of Technology in Pasadena, supports the U.S. astronomical community.


Dawn's mission is managed by JPL for NASA's Science Mission Directorate in Washington. Dawn is a project of the directorate's Discovery Program, managed by NASA's Marshall Space Flight Center in Huntsville, Ala. UCLA is responsible for overall Dawn mission science. Orbital Sciences Corp. in Dulles, Va., designed and built the spacecraft. The German Aerospace Center, the Max Planck Institute for Solar System Research, the Italian Space Agency and the Italian National Astrophysical Institute are international partners on the mission team. Caltech manages JPL for NASA.


More information about Herschel is online at: http://www.esa.int/SPECIALS/herschel. More information about NASA's role in Herschel is available at: http://www.nasa.gov/herschel. For more information about NASA's Dawn mission, visit: http://www.nasa.gov/dawn.

Whitney Clavin 818-648-9734

Jet Propulsion Laboratory, Pasadena, Calif.

whitney.clavin@jpl.nasa.gov


J.D. Harrington 202-358-5241

Headquarters, Washington

j.d.harrington@nasa.gov


2014-020
Posted by Nelio Inacio at 1:58 PM 0 comments

NEOWISE Celebrates First Month of Operations After Reactivation

NEOWISE Celebrates First Month of Operations After Reactivation:

Asteroid Tracks Among the Stars
More than 100 asteroids were captured in this view from NASA's Wide-field Infrared Survey Explorer, or WISE, during its primary all-sky survey. Image credit: NASA/JPL-Caltech/UCLA
› Full image and caption


January 23, 2014

Mission Status Report

In its first 25 days of operations, the newly reactivated NEOWISE mission has detected 857 minor bodies in our solar system, including 22 near-Earth objects (NEOs) and four comets. Three of the NEOs are new discoveries; all three are hundreds of meters in diameter and dark as coal.

The mission has just passed its post-restart survey readiness review, and the project has verified that the ability to measure asteroid positions and brightness is as good as it was before the spacecraft entered hibernation in early 2011. At the present rate, NEOWISE is observing and characterizing approximately one NEO per day, giving astronomers a much better idea of the objects' sizes and compositions.

Out of the more than 10,500 NEOs that have been discovered to date, only about 10 percent have had any physical measurements made of them; the reactivated NEOWISE will more than double that number.

JPL manages the NEOWISE mission for NASA's Science Mission Directorate in Washington. 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 on NEOWISE is online at: http://www.jpl.nasa.gov/wise/ .

Whitney Clavin/DC Agle 818-354-5011

Jet Propulsion Laboratory, Pasadena, Calif.

whitney.clavin@jpl.nasa.gov / agle@jpl.nasa.gov



2014-023
Posted by Nelio Inacio at 1:57 PM 0 comments

NASA Preparing for 2014 Comet Watch at Mars

NASA Preparing for 2014 Comet Watch at Mars:

Comet 2013 A1 Siding Spring
NASA's NEOWISE mission captured images of comet C/2013 A1 Siding Spring, which is slated to make a close pass by Mars on Oct. 19, 2014. The infrared pictures reveal a comet that is active and very dusty even though it was about 355 million miles (571 million kilometers) away from the sun on Jan. 16, 2014, when this picture was taken. Image credit: NASA/JPL-Caltech
› Full image and caption


January 28, 2014

This spring, NASA will be paying cautious attention to a comet that could put on a barnstorming show at Mars on Oct. 19, 2014.

On that date, comet 2013 A1 Siding Spring will buzz Mars about 10 times closer than any identified comet has ever flown past Earth.

Spacecraft at Mars might get a good look at the nucleus of comet Siding Spring as it heads toward the closest approach, roughly 86,000 miles (138,000 kilometers) from the planet, give or take a few percent. On the other hand, dust particles that the comet nucleus sheds this spring could threaten orbiting spacecraft at Mars in October.

The level of risk won't be known for months, but NASA is already evaluating possible precautionary measures as it prepares for studying the comet.

"Our plans for using spacecraft at Mars to observe comet Siding Spring will be coordinated with plans for how the orbiters will duck and cover, if we need to do that," said Rich Zurek, Mars Exploration Program chief scientist at NASA's Jet Propulsion Laboratory, Pasadena, Calif.

Comet Siding Spring, formally named C/2013 A1, was discovered on Jan. 3, 2013, from Australia's Siding Spring Observatory. At the time, it was farther from the sun than Jupiter is. Subsequent observations enabled scientists at JPL and elsewhere to calculate the trajectory the comet will follow as it swings past Mars. Observations in 2014 will continue to refine knowledge of the comet's path, but in approximate terms, Siding Spring's nucleus will come about as close to Mars as one-third of the distance between Earth and the moon.

Comet Ready for Its Close-up

Observations of comet Siding Spring are planned using resources on Earth, orbiting Earth, on Mars and orbiting Mars, and some are already underway.  NASA's Hubble Space Telescope and the NEOWISE mission have observed the comet this month both to characterize this first-time visitor from the Oort cloud and to study dust particle sizes and amounts produced by the comet for understanding potential risks to the Mars orbiters. Infrared imaging by NEOWISE reveals a comet that is active and dusty, even though still nearly three-fourths as far from the sun as Jupiter is. Ground-based observatories such as the NASA Infrared Telescope Facility are also expected to join in as the comet becomes favorably positioned for viewing.

As the comet nears Mars, NASA assets there will be used to study this visitor from distant reaches of the solar system.

"We could learn about the nucleus -- its shape, its rotation, whether some areas on its surface are darker than others," Zurek said.

Researchers using spacecraft at Mars gained experience at trying to observe a different comet in 2013, as comet ISON (formally C/2012 S1) approached Mars. That comet's Mars-flyby distance was about 80 times farther than Siding Spring's will be. Another difference is that ISON continued inward past Mars for nearly two months, briefly becoming visible to some unaided-eye skywatchers on Earth before flying very close to the sun and disintegrating. Siding Spring will reach its closest approach to the sun just six days after its Mars flyby. It won't put on a show for Earth, and it won't return to the inner solar system for about a million years.

At comet Siding Spring's flyby distance, the High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter could provide imagery with resolution of dozens of pixels across the diameter of the nucleus. When HiRISE observed comet ISON, the nucleus was less than one pixel across. ISON did not get bright enough to make itself visible to other cameras at Mars that made attempted observations, but Siding Spring could provide a better observation opportunity.

Cameras on the Mars rovers Curiosity and Opportunity might watch for meteors in the sky that would be an indication of the abundance of particles in the comet's tail, though the geometry of the flyby would put most of the meteors in daytime sky instead of dark sky.

"A third aspect for investigation could be what effect the infalling particles have on the upper atmosphere of Mars," Zurek said. "They might heat it and expand it, not unlike the effect of a global dust storm." Infrared-sensing instruments on Mars Reconnaissance Orbiter and Odyssey might be used to watch for that effect.

Assessing Possible Hazards to Mars Orbiters

One trait Siding Spring shares with ISON is unpredictability about how much it will brighten in the months before passing Mars. The degree to which Siding Spring brightens this spring will be an indicator of how much hazard it will present to spacecraft at Mars.

"It's way too early for us to know how much of a threat Siding Spring will be to our orbiters," JPL's Soren Madsen, Mars Exploration Program chief engineer, said last week. "It could go either way. It could be a huge deal or it could be nothing -- or anything in between."

The path the nucleus will take is now known fairly well. The important unknowns are how much dust will come off the nucleus, when it will come off, and the geometry of the resulting coma and tail of the comet.

During April and May, the comet will cross the range of distances from the sun at which water ice on a comet's surface typically becomes active -- vaporizing and letting dust particles loose. Dust ejected then could get far enough from the nucleus by October to swarm around Mars.

"How active will Siding Spring be in April and May? We'll be watching that," Madsen said. "But if the red alarm starts sounding in May, it would be too late to start planning how to respond. That's why we're doing what we're doing right now."

Two key strategies to lessen risk are to get orbiters behind Mars during the minutes of highest risk and to orient orbiters so that the most vulnerable parts are not in the line of fire.

The Martian atmosphere, thin as it is, is dense enough to prevent dust from the comet from becoming a hazard to NASA's two Mars rovers active on the surface. Three orbiters are currently active at Mars:  NASA's Mars Reconnaissance Orbiter (MRO) and Mars Odyssey, and the European Space Agency's Mars Express. Two more departed Earth in late 2013 and are due to enter orbit around Mars about three weeks before the comet Siding Spring flyby: NASA's Mars Atmosphere and Volatile Evolution (MAVEN) and India's Mars Orbiter Mission.

Orbiters are designed with the risk of space-dust collisions in mind. Most such collisions do not damage a mission. Design factors such as blanketing and protected placement of vulnerable components help. Over a five-year span for a Mars orbiter, NASA figures on a few percent chance of significant damage to a spacecraft from the background level of impacts from such particles, called meteoroids. Whether the Siding Spring level will pack that much hazard -- or perhaps greater than 10 times more -- into a few hours will depend on how active it becomes.

This comet is orbiting the sun in almost the opposite direction as Mars and the other planets. The nucleus and the dust particles it sheds will be travelling at about 35 miles (56 kilometers) per second, relative to the Mars orbiters. That's about 50 times faster than a bullet from a high-powered rifle and double or triple the velocity of background meteoroid impacts.

Cautionary Preparations

If managers choose to position orbiters behind Mars during the peak risk, the further in advance any orbit-adjustment maneuvers can be made, the less fuel will be consumed. Advance work is also crucial for the other main option: reorienting a spacecraft to keep its least-vulnerable side facing the oncoming stream of comet particles. The safest orientation in terms of comet dust may be a poor one for maintaining power or communications.

"These changes would require a huge amount of testing," Madsen said. "There's a lot of preparation we need to do now, to prepare ourselves in case we learn in May that the flyby will be hazardous."

JPL, a division of the California Institute of Technology, Pasadena, manages the NASA's Mars Exploration Program for NASA's Science Mission Directorate, Washington. For more information about the flyby of Mars by comet Siding Spring, visit http://mars.nasa.gov/comets/sidingspring/ .

For more about the Mars Exploration Program, visit http://mars.jpl.nasa.gov .

Guy Webster 818-354-6278

Jet Propulsion Laboratory, Pasadena, Calif.

guy.webster@jpl.nasa.gov

2014-026
Posted by Nelio Inacio at 1:56 PM 0 comments

NASA and ESA Space Telescopes Help Solve Mystery of Burned-Out Galaxies

NASA and ESA Space Telescopes Help Solve Mystery of Burned-Out Galaxies:

Development of Massive Elliptical Galaxies
This graphic shows the evolutionary sequence in the growth of massive elliptical galaxies over 13 billion years, as gleaned from space-based and ground-based telescopic observations. The growth of this class of galaxies is quickly driven by rapid star formation and mergers with other galaxies. Image Credit: NASA, ESA, S. Toft (Niels Bohr Institute), and A. Feild (STScI)
› Larger image


January 29, 2014

Astronomers using NASA's Hubble and Spitzer space telescopes, and Europe's Herschel Space Observatory, have pieced together the evolutionary sequence of compact elliptical galaxies that erupted and burned out early in the history of the universe.

Enabled by Hubble's infrared imaging capabilities, astronomers have assembled for the first time a representative spectroscopic sampling of ultra-compact, burned-out elliptical galaxies -- galaxies whose star formation was finished when the universe was only 3 billion years old, less than a quarter of its current estimated age of 13.8 billion years.

The research, supported by several ground-based telescopes, solves a 10-year-old mystery about the growth of the most massive elliptical galaxies we see today. It provides a clear picture of the formation of the most massive galaxies in the universe, from their initial burst of star formation through their development of dense stellar cores, to their ultimate reality as giant ellipticals.

"We at last show how these compact galaxies can form, how it happened, and when it happened. This basically is the missing piece in the understanding of how the most massive galaxies formed, and how they evolved into the giant ellipticals of today," said Sune Toft of the Dark Cosmology Center at the Niels Bohr Institute in Copenhagen, Denmark, who is the leader of this study.

"This had been a great mystery for many years because just 3 billion years after the big bang we see that half of the most massive galaxies have already completed their star formation."

Through the research, astronomers have determined the compact ellipticals voraciously consumed the gas available for star formation, to the point they could not create new stars, and then merged with smaller galaxies to form giant ellipticals. The stars in the burned-out galaxies were packed 10 to 100 times more densely than in equally massive elliptical galaxies seen in the nearby universe today, and that surprised astronomers, according to Toft.

To develop the evolutionary sequence for ultra-compact, burned-out galaxies, Toft's team assembled, for the first time, representative samples of two galaxy populations using the rich dataset in Hubble's COSMOS (Cosmic Evolution Survey) program.

One group of galaxies is the compact ellipticals. The other group contains galaxies that are highly obscured with dust and undergoing rapid star formation at rates thousands of times faster than observed in the Milky Way. Starbursts in these dusty galaxies likely were ignited when two gas-rich galaxies collided. These galaxies are so dusty that they are almost invisible at optical wavelengths, but they shine bright at submillimeter wavelengths, where they were first identified nearly two decades ago by the Submillimeter Common-User Bolometer Array (SCUBA) camera on the James Clerk Maxwell Telescope in Hawaii.

Toft's team started by constructing the first representative sample of compact elliptical galaxies with accurate sizes and spectroscopic redshifts, or distances, measured with Hubble's Cosmic Assembly Near-Infrared Deep Extragalactic Legacy Survey (CANDELS) and 3D-HST (3D- Hubble Space Telescope) programs. 3D-HST is a near-infrared spectroscopic survey to study the physical processes that shape galaxies in the distant universe. The astronomers combined these data with observations from the Subaru telescope in Hawaii, and Spitzer. This allowed for accurate stellar age estimates, from which they concluded compact elliptical galaxies formed in intense starbursts inside the galaxies that preceded them by as long as two billion years.

Next, the team made the first representative sample of the most distant submillimeter galaxies using COSMOS data from the Hubble, Spitzer and Herschel space telescopes, and ground-based telescopes such as Subaru, the James Clerk Maxwell Telescope, and the Submillimeter Array, all located in Hawaii. This multi-spectral information, stretching from optical light through submillimeter wavelengths, yielded a full suite of information about the sizes, stellar masses, star-formation rates, dust content, and precise distances of the dust-enshrouded galaxies that were present early in the universe.

When Toft's team compared the samples of the two galaxy populations, it discovered an evolutionary link between the compact elliptical galaxies and the submillimeter galaxies. The observations show that the violent starbursts in the dusty galaxies had the same characteristics that would have been predicted for progenitors to the compact elliptical galaxies. Toft's team also calculated the intense starburst activity inside the submillimeter galaxies lasted only about 40 million years before the interstellar gas supply was exhausted.

The results appear in the Jan. 29 online issue of The Astrophysical Journal. For related and high resolution imagery, visit: http://hubblesite.org/news/2014/10 .

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 the California Institute of Technology in Pasadena. Spacecraft operations are based at Lockheed Martin Space Systems Company, Littleton, Colorado. 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 .

Herschel is a European Space Agency mission, with science instruments provided by consortia of European institutes and with important participation by NASA. While the observatory stopped making science observations in April 2013, after running out of liquid coolant, as expected, scientists continue to analyze its data. NASA's Herschel Project Office is based at JPL. JPL contributed mission-enabling technology for two of Herschel's three science instruments. The NASA Herschel Science Center, part of the Infrared Processing and Analysis Center at Caltech, supports the U.S. astronomical community. Caltech manages JPL for NASA.

More information is online at http://www.herschel.caltech.edu , http://www.nasa.gov/herschel and http://www.esa.int/SPECIALS/Herschel .

Whitney Clavin 818-354-4673

Jet Propulsion Laboratory, Pasadena, Calif.

whitney.clavin@jpl.nasa.gov


2014-030
Posted by Nelio Inacio at 1:56 PM 0 comments

Where the Wild Stars Are

Where the Wild Stars Are:

Storm of Stars in the Trifid Nebula
Radiation and winds from massive stars have blown a cavity into the surrounding dust and gas, creating the Trifid nebula, as seen here in infrared light by NASA's Wide-field Infrared Survey Explorer, or WISE. Image credit: NASA/JPL-Caltech/UCLA
› Larger image


January 29, 2014

A storm of stars is brewing in the Trifid nebula, as seen in this view from NASA's Wide-field Infrared Survey Explorer, or WISE. The stellar nursery, where baby stars are bursting into being, is the yellow-and-orange object dominating the picture. Yellow bars in the nebula appear to cut a cavity into three sections, hence the name Trifid nebula.

Colors in this image represent different wavelengths of infrared light detected by WISE. The main green cloud is made up of hydrogen gas. Within this cloud is the Trifid nebula, where radiation and winds from massive stars have blown a cavity into the surrounding dust and gas, and presumably triggered the birth of new generations of stars. Dust glows in infrared light, so the three lines that make up the Trifid, while appearing dark in visible-light views, are bright when seen by WISE.

The blue stars scattered around the picture are older, and they lie between Earth and the Trifid nebula. The baby stars in the Trifid will eventually look similar to those foreground stars. The red cloud at upper right is gas heated by a group of very young stars.

The Trifid nebula is located 5,400 light-years away in the constellation Sagittarius.

Blue represents light emitted at 3.4-micron wavelengths, and cyan (blue-green) represents 4.6 microns, both of which come mainly from hot stars. Relatively cooler objects, such as the dust of the nebula, appear green and red. Green represents 12-micron light and red, 22-micron light.

NASA's Jet Propulsion Laboratory, Pasadena, Calif., manages and operates the recently activated NEOWISE asteroid-hunting mission for NASA's Science Mission Directorate. The results presented here are from the WISE all-sky survey mission, which operated before NEOWISE, using the same spacecraft, in 2010 and 2011. WISE 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, Pasadena. Caltech manages JPL for NASA.

Whitney Clavin 818-354-4673

Jet Propulsion Laboratory, Pasadena, Calif.

whitney.clavin@jpl.nasa.gov

2014-029
Posted by Nelio Inacio at 1:55 PM 0 comments

NASA-Sponsored 'Disk Detective' Lets Public Search for New Planetary Nurseries

NASA-Sponsored 'Disk Detective' Lets Public Search for New Planetary Nurseries:

Herbig-Haro 30 is the prototype of a gas-rich 'Young Stellar Object' disk around a star
Herbig-Haro 30 is the prototype of a gas-rich "young stellar object" disk around a star. The dark disk spans 40 billion miles (64 billion kilometers) in this image from NASA's Hubble Space Telescope, cutting the bright nebula in two and blocking the central star from direct view. Image credit NASA/Hubble/STScI
› Full image and caption


January 30, 2014

NASA is inviting the public to help astronomers discover embryonic planetary systems hidden among data from the agency's Wide-field Infrared Survey Explorer (WISE) mission through a new website, DiskDetective.org.


Disk Detective is NASA's largest crowdsourcing project whose primary goal is to produce publishable scientific results. It exemplifies a new commitment to crowdsourcing and open data by the United States government.


"Through Disk Detective, volunteers will help the astronomical community discover new planetary nurseries that will become future targets for NASA's Hubble Space Telescope and its successor, the James Webb Space Telescope," said James Garvin, the chief scientist for NASA Goddard's Sciences and Exploration Directorate.


WISE was designed to survey the entire sky at infrared wavelengths. From a perch in Earth orbit, the spacecraft completed two scans of the entire sky between 2010 and 2011. It took detailed measurements on more than 745 million objects, representing the most comprehensive survey of the sky at mid-infrared wavelengths currently available.


Astronomers have used computers to search this haystack of data for planet-forming environments and narrowed the field to about a half-million sources that shine brightly in infrared, indicating they may be "needles": dust-rich disks that are absorbing their star's light and reradiating it as heat.


"Planets form and grow within disks of gas, dust and icy grains that surround young stars, but many details about the process still elude us," said Marc Kuchner, an astrophysicist at NASA's Goddard Space Flight Center in Greenbelt, Md. "We need more examples of planet-forming habitats to better understand how planets grow and mature."


But galaxies, interstellar dust clouds and asteroids also glow in infrared, which stymies automated efforts to identify planetary habitats. There may be thousands of nascent solar systems in the WISE data, but the only way to know for sure is to inspect each source by eye, which poses a monumental challenge.


Public participation in scientific research is a type of crowdsourcing known as citizen science. It allows the public to make critical contributions to the fields of science, technology, engineering and mathematics by collecting, analyzing and sharing a wide range of data. NASA uses citizen science to engage the public in problem-solving.


Kuchner recognized that spotting planetary nurseries is a perfect opportunity for crowdsourcing. He arranged for NASA to team up with the Zooniverse, a collaboration of scientists, software developers and educators who collectively develop and manage citizen science projects on the Internet. The result of their combined effort is Disk Detective.


Disk Detective incorporates images from WISE and other sky surveys in brief animations the website calls flip books. Volunteers view a flip book and classify the object based on simple criteria, such as whether the image is round or includes multiple objects. By collecting this information, astronomers will be able to assess which sources should be explored in greater detail, for example, to search for planets outside our solar system.


"Disk Detective's simple and engaging interface allows volunteers from all over the world to participate in cutting-edge astronomy research that wouldn't even be possible without their efforts," said Laura Whyte, director of citizen science at Adler Planetarium in Chicago, Ill., a founding partner of the Zooniverse collaboration.


The project aims to find two types of developing planetary environments. The first, known as a young stellar object disk, typically is less than 5 million years old, contains large quantities of gas, and often is found in or near young star clusters. For comparison, our own solar system is 4.6 billion years old. The second planetary environment, known as a debris disk, tends to be older than 5 million years, possesses little or no gas, and contains belts of rocky or icy debris that resemble the asteroid and Kuiper belts found in our own solar system. Vega and Fomalhaut, two of the brightest stars in the sky, host debris disks.


WISE was shut down in 2011 after its primary mission was completed. But in September 2013, it was reactivated, renamed Near-Earth Object Wide-field Infrared Survey Explorer (NEOWISE), and given a new mission, which is to assist NASA's efforts to identify the population of potentially hazardous near-Earth objects (NEOs). NEOWISE also can assist in characterizing previously detected asteroids that could be considered potential targets for future exploration missions.


NASA's Jet Propulsion Laboratory in Pasadena, Calif., manages and operates WISE for NASA's Science Mission Directorate. The WISE mission was selected competitively under NASA's Explorers Program managed by the agency's Goddard Space Flight Center. 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, which manages JPL for NASA.


For more information about Disk Detective, please visit: http://www.diskdetective.org .


For more information about NASA's WISE mission, visit: http://www.nasa.gov/wise .

Whitney Clavin 818-354-4673

Jet Propulsion Laboratory, Pasadena, Calif.

whitney.clavin@jpl.nasa.gov


J.D. Harrington 202-358-5241

Headquarters, Washington

j.d.harrington@nasa.gov


2014-032
Posted by Nelio Inacio at 1:54 PM 0 comments
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