Monday, July 21, 2014

Massive Black Hole Duo: Possible Sighting by NASA's WISE

Massive Black Hole Duo: Possible Sighting by NASA's WISE:

Two Black Holes on Way to Becoming One
Two black holes are entwined in a gravitational tango in this artist's conception. Supermassive black holes at the hearts of galaxies are thought to form through the merging of smaller, yet still massive black holes, such as the ones depicted here. Image credit: NASA
› Full image and caption

December 03, 2013

Astronomers have spotted what appear to be two supermassive black holes at the heart of a remote galaxy, circling each other like dance partners. The incredibly rare sighting was made with the help of NASA's Wide-field Infrared Survey Explorer, or WISE.


Follow-up observations with the Australian Telescope Compact Array near Narrabri, Australia, and the Gemini South telescope in Chile, revealed unusual features in the galaxy, including a lumpy jet thought to be the result of one black hole causing the jet of the other to sway.


"We think the jet of one black hole is being wiggled by the other, like a dance with ribbons," said Chao-Wei Tsai of NASA's Jet Propulsion Laboratory, Pasadena, Calif., who is lead author of a paper on the findings appearing in the Dec. 10 issue of Astrophysical Journal. "If so, it is likely the two black holes are fairly close and gravitationally entwined."


The findings could teach astronomers more about how supermassive black holes grow by merging with each other.


The WISE satellite scanned the entire sky twice in infrared wavelengths before being put into hibernation in 2011. NASA recently gave the spacecraft a second lease on life, waking it up to search for asteroids, in a project called NEOWISE.


The new study took advantage of previously released all-sky WISE data. Astronomers sifted through images of millions of actively feeding supermassive black holes spread throughout our sky before an oddball, also known as WISE J233237.05-505643.5, jumped out.


"At first we thought this galaxy's unusual properties seen by WISE might mean it was forming new stars at a furious rate," said Peter Eisenhardt, WISE project manager at NASA's Jet Propulsion Laboratory, Pasadena, Calif., and a co-author of the study. "But on closer inspection, it looks more like the death spiral of merging giant black holes."


Almost every large galaxy is thought to harbor a supermassive black hole filled with the equivalent in mass of up to billions of suns. How did the black holes grow so large? One way is by swallowing ambient materials. Another way is through galactic cannibalism. When galaxies collide, their massive black holes sink to the center of the new structure, becoming locked in a gravitational tango. Eventually, they merge into one even-more-massive black hole.


The dance of these black hole duos starts out slowly, with the objects circling each other at a distance of about a few thousand light-years. So far, only a few handfuls of supermassive black holes have been conclusively identified in this early phase of merging. As the black holes continue to spiral in toward each other, they get closer, separated by just a few light-years.


It is these close-knit black holes, also called black hole binaries, that have been the hardest to find. The objects are usually too small to be resolved even by powerful telescopes. Only a few strong candidates have been identified to date, all relatively nearby. The new WISE J233237.05-505643.5 is a new candidate, and located much farther away, at 3.8 billion light-years from Earth.


Radio images with the Australian Telescope Compact Array were key to identifying the dual nature of WISE J233237.05-505643.5. Supermassive black holes at the cores of galaxies typically shoot out pencil-straight jets, but, in this case, the jet showed a zigzag pattern. According to the scientists, a second massive black hole could, in essence, be pushing its weight around to change the shape of the other black hole's jet.


Visible-light spectral data from the Gemini South telescope in Chile showed similar signs of abnormalities, thought to be the result of one black hole causing disk material surrounding the other black hole to clump. Together, these and other signs point to what is probably a fairly close-knit set of circling black holes, though the scientists can't say for sure how much distance separates them.


"We note some caution in interpreting this mysterious system," said Daniel Stern of JPL, a co-author of the study. "There are several extremely unusual properties to this system, from the multiple radio jets to the Gemini data, which indicate a highly perturbed disk of accreting material around the black hole, or holes. Two merging black holes, which should be a common event in the universe, would appear to be simplest explanation to explain all the current observations."


The final stage of merging black holes is predicted to send gravitational waves rippling through space and time. Researchers are actively searching for these waves using arrays of dead stars called pulsars in hopes of learning more about the veiled black hole dancers (see http://www.nasa.gov/centers/jpl/news/pulsar20131106.html ).


The technical paper is online at http://arxiv.org/abs/1310.2257 .


NASA's Jet Propulsion Laboratory, Pasadena, Calif., manages and operates the WISE mission 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 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://www.jpl.nasa.gov/wise .

Whitney Clavin 818-354-4673

Jet Propulsion Laboratory, Pasadena, Calif.

whitney.clavin@jpl.nasa.gov


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NASA's Dawn Fills out its Ceres Dance Card

NASA's Dawn Fills out its Ceres Dance Card:

On the Way to Ceres
This artist's concept shows NASA's Dawn spacecraft heading toward the dwarf planet Ceres. Dawn spent nearly 14 months orbiting Vesta, the second most massive object in the main asteroid belt between Mars and Jupiter, from 2011 to 2012. It is heading towards Ceres, the largest member of the asteroid belt. When Dawn arrives, it will be the first spacecraft to go into orbit around two destinations in our solar system beyond Earth. Image credit: NASA/JPL-Caltech
› Full image and caption

December 03, 2013

It's going to be a ball when NASA's Dawn spacecraft finally arrives at the dwarf planet Ceres, and mission managers have now inked in the schedule on Dawn's dance card.


Dawn has been cruising toward Ceres, the largest object in the main asteroid belt between Mars and Jupiter, since September 2012. That's when it departed from its first dance partner, Vesta.


Ceres presents an icy -- possibly watery -- counterpoint to the dry Vesta, where Dawn spent almost 14 months. Vesta and Ceres are two of the largest surviving protoplanets -- bodies that almost became planets -- and will give scientists clues about the planet-forming conditions at the dawn of our solar system.


When Dawn enters orbit around Ceres, it will be the first spacecraft to see a dwarf planet up-close and the first spacecraft to orbit two solar system destinations beyond Earth.


"Our flight plan around Ceres will be choreographed to be very similar to the strategy that we successfully used around Vesta," said Bob Mase, Dawn's project manager at NASA's Jet Propulsion Laboratory, Pasadena, Calif. "This approach will build on that and enable scientists to make direct comparisons between these two giants of the asteroid belt."


As a prelude, the team will begin approach operations in late January 2015. The next month, Ceres will be big enough in Dawn's view to be imaged and used for navigation purposes. Dawn will arrive at Ceres -- or, more accurately, it will be captured by Ceres' gravity -- in late March or the beginning of April 2015.


Dawn will make its first full characterization of Ceres later in April, at an altitude of about 8,400 miles (13,500 kilometers) above the icy surface. Then, it will spiral down to an altitude of about 2,750 miles (4,430 kilometers), and obtain more science data in its survey science orbit. This phase will last for 22 days, and is designed to obtain a global view of Ceres with Dawn's framing camera, and global maps with the visible and infrared mapping spectrometer (VIR).


Dawn will then continue to spiral its way down to an altitude of about 920 miles (1,480 kilometers), and in August 2015 will begin a two-month phase known as the high-altitude mapping orbit. During this phase, the spacecraft will continue to acquire near-global maps with the VIR and framing camera at higher resolution than in the survey phase. The spacecraft will also image in "stereo" to resolve the surface in 3-D.


Then, after spiraling down for two months, Dawn will begin its closest orbit around Ceres in late November, at a distance of about 233 miles (375 kilometers). The dance at low-altitude mapping orbit will be a long waltz -- three months -- and is specifically designed to acquire data with Dawn's gamma ray and neutron detector (GRaND) and gravity investigation. GRaND will reveal the signatures of the elements on and near the surface. The gravity experiment will measure the tug of the dwarf planet, as monitored by changes in the high-precision radio link to NASA's Deep Space Network on Earth.


At this low-altitude mapping orbit, Dawn will begin using a method of pointing control that engineers have dubbed "hybrid" mode because it utilizes a combination of reaction wheels and thrusters to point the spacecraft. Up until this final mission phase, Dawn will have used just the small thruster jets, which use a fuel called hydrazine, to control its orientation and pointing. While it is possible to explore Ceres completely using only these jets, mission managers want to conserve precious fuel. At this lowest orbit, using two of the reaction wheels to help with pointing will provide the biggest hydrazine savings. So Dawn will be spinning up two of the gyroscope-like devices to aid the thrusters.


In 2011, the Dawn team prepared the capability to operate in a hybrid mode, but it wasn't needed during the Vesta mission. It was only when a second (of four) reaction wheels developed excessive friction while Dawn was leaving Vesta in 2012 that mission managers decided to use the hybrid mode at Ceres. To prove the technique works, Dawn engineers completed a 27-hour in-flight test of the hybrid mode, ending on Nov. 13. It operated just as expected.


"The successful test of this new way to control our orientation gives us great confidence that we'll have a steady hand at Ceres, which will enable us to get really close to a world that we only know now as a fuzzy dot amidst the stars," said Marc Rayman, Dawn's chief engineer and mission director, based at JPL.


Of course, mission planners have built some extra days into the schedule to account for the small uncertainty in the efficiency of the solar arrays at such a large distance from the sun, where sunlight will be very faint. The solar arrays provide power to the ion propulsion system, in addition to operating power for the spacecraft and instruments. Mission planners also account for potential variations in the gravity field of Ceres, which will not be known precisely until Dawn measures them.


"We are expecting changes when we get to Ceres and, fortunately, we built a very capable spacecraft and developed flexible plans to accommodate the unknowns," said Rayman. "There's great excitement in the unexpected -- that's part of the thrill of exploration."


Starting on Dec. 27, Dawn will be closer to Ceres than it will be to Vesta.


"This transition makes us eager to see what secrets Ceres will reveal to us when we get up close to this ancient, giant, icy body," said Christopher Russell, Dawn's principal investigator, based at UCLA. "While Ceres is a lot bigger than the candidate asteroids that NASA is working on sending humans to, many of these smaller bodies are produced by collisions with larger asteroids such as Ceres and Vesta. It is of much interest to determine the nature of small asteroids produced in collisions with Ceres. These might be quite different from the small rocky asteroids associated with Vesta collisions."


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. The California Institute of Technology in Pasadena manages JPL for NASA.


To learn more about hybrid mode at Ceres, read Rayman's Dawn Journal [link].


For more information about Dawn, visit: http://www.nasa.gov/dawn and http://dawn.jpl.nasa.gov .


To learn more about hybrid mode at Ceres, read Rayman's Dawn Journal .

Jia-Rui Cook 818-354-0850

Jet Propulsion Laboratory, Pasadena, Calif.

jccook@jpl.nasa.gov


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NASA's Cassini Spacecraft Obtains Best Views of Saturn Hexagon

NASA's Cassini Spacecraft Obtains Best Views of Saturn Hexagon:

In Full View: Saturn's Streaming Hexagon
This colorful view from NASA's Cassini mission is the highest-resolution view of the unique six-sided jet stream at Saturn's north pole known as "the hexagon." This movie, made from images obtained by Cassini's imaging cameras, is the first to show the hexagon in color filters, and the first movie to show a complete view from the north pole down to about 70 degrees north latitude. Image credit: NASA/JPL-Caltech/SSI/Hampton University
› Full image and caption


December 04, 2013

NASA's Cassini spacecraft has obtained the highest-resolution movie yet of a unique six-sided jet stream, known as the hexagon, around Saturn's north pole.


This is the first hexagon movie of its kind, using color filters, and the first to show a complete view of the top of Saturn down to about 70 degrees latitude. Spanning about 20,000 miles (30,000 kilometers) across, the hexagon is a wavy jet stream of 200-mile-per-hour winds (about 322 kilometers per hour) with a massive, rotating storm at the center. There is no weather feature exactly, consistently like this anywhere else in the solar system.


"The hexagon is just a current of air, and weather features out there that share similarities to this are notoriously turbulent and unstable," said Andrew Ingersoll, a Cassini imaging team member at the California Institute of Technology in Pasadena. "A hurricane on Earth typically lasts a week, but this has been here for decades -- and who knows -- maybe centuries."


Weather patterns on Earth are interrupted when they encounter friction from landforms or ice caps. Scientists suspect the stability of the hexagon has something to do with the lack of solid landforms on Saturn, which is essentially a giant ball of gas.


Better views of the hexagon are available now because the sun began to illuminate its interior in late 2012. Cassini captured images of the hexagon over a 10-hour time span with high-resolution cameras, giving scientists a good look at the motion of cloud structures within.


They saw the storm around the pole, as well as small vortices rotating in the opposite direction of the hexagon. Some of the vortices are swept along with the jet stream as if on a racetrack. The largest of these vortices spans about 2,200 miles (3,500 kilometers), or about twice the size of the largest hurricane recorded on Earth.


Scientists analyzed these images in false color, a rendering method that makes it easier to distinguish differences among the types of particles suspended in the atmosphere -- relatively small particles that make up haze -- inside and outside the hexagon.


"Inside the hexagon, there are fewer large haze particles and a concentration of small haze particles, while outside the hexagon, the opposite is true," said Kunio Sayanagi, a Cassini imaging team associate at Hampton University in Virginia. "The hexagonal jet stream is acting like a barrier, which results in something like Earth's Antarctic ozone hole."


The Antarctic ozone hole forms within a region enclosed by a jet stream with similarities to the hexagon. Wintertime conditions enable ozone-destroying chemical processes to occur, and the jet stream prevents a resupply of ozone from the outside. At Saturn, large aerosols cannot cross into the hexagonal jet stream from outside, and large aerosol particles are created when sunlight shines on the atmosphere. Only recently, with the start of Saturn's northern spring in August 2009, did sunlight begin bathing the planet's northern hemisphere.


"As we approach Saturn's summer solstice in 2017, lighting conditions over its north pole will improve, and we are excited to track the changes that occur both inside and outside the hexagon boundary," said Scott Edgington, Cassini deputy project scientist at NASA's Jet Propulsion Laboratory in Pasadena, Calif.


A black-and-white version of the imaging camera movie and movies obtained by Cassini's visual and infrared mapping spectrometer are also tools Cassini scientists can use to look at wind speeds and the mini-storms inside the jet stream.


Cassini launched in 1997 and arrived at Saturn on July 1, 2004. Its mission is scheduled to end in September 2017. The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. JPL manages the mission for NASA's Science Mission Directorate in Washington. JPL designed, developed and assembled the Cassini orbiter and its two onboard cameras. The imaging team is based at the Space Science Institute, Boulder, Colo.


A Google+ Hangout to discuss these results and other Cassini images will take place today at 12:30 p.m. PST (3:30 p.m. EST): http://bit.ly/askcassini .


The event will be broadcast live on NASA Television and streamed on the agency's website. For information on NASA TV, visit: http://www.nasa.gov/ntv .


The event will also be streamed live on Ustream with a moderated chat available at: http://www.ustream.tv/nasajpl2 .


Questions can be asked on the Google Hangout event page, in the chat box on the Ustream site and via Twitter using the hashtag #askCassini.


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

Jia-Rui C. Cook 818-354-0850

Jet Propulsion Laboratory, Pasadena, Calif.

jccook@jpl.nasa.gov


Dwayne Brown 202-358-1726

NASA Headquarters, Washington

dwayne.c.brown@nasa.gov


2013-350
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Thinking Inside the Box, Launching into Space

Thinking Inside the Box, Launching into Space:

NASA CubeSats Heading into Orbit
The NROL-39 GEMSat mission lifted off from California's Vandenberg Air Force Base on Dec. 5, 2013, aboard a United Launch Alliance Atlas V rocket. The mission includes two NASA Earth-orbiting cube satellites ("CubeSats") led by NASA's Jet Propulsion Laboratory, Pasadena, Calif.: the Intelligent Payload Experiment (IPEX) and M-Cubed/COVE. Image credit: P. Corkery/ULA

› Larger image

December 06, 2013

Two tiny, cube-shaped research satellites hitched a ride to Earth orbit to validate new hardware and software technologies for future NASA Earth-observing instruments.


The cube satellites, or "CubeSats," which typically have a volume of exactly 33.814 ounces (1 liter), were launched on a United Launch Alliance Atlas V rocket at 11:14 p.m. PST last night (Dec. 5) from California's Vandenberg Air Force Base as part of the NROL-39 GEMSat mission. Led by NASA's Jet Propulsion Laboratory, Pasadena, Calif., and developed with university and industry partners, these two CubeSats will help enable near-real-time processing capabilities relevant to future climate science measurements.


One of the CubeSats that launched was developed in collaboration with California Polytechnic State University, San Luis Obispo, and is called the Intelligent Payload Experiment, or IPEX. It enables imagery to be transmitted more rapidly from satellite missions back to Earth. By using new software and algorithms, the spacecraft can sift through the data, looking only for the most important images that the scientists urgently need on the ground. This method is designed to speed delivery time of critical data products from days to minutes.


"IPEX will demonstrate software that will enable future NASA missions to recognize science events such as flooding, volcanism and wildfires, and respond by sending alerts and autonomously acquiring follow-up imagery," said Steve Chien of JPL, principal investigator for the IPEX mission.


The other CubeSat launched is the Michigan Multipurpose Mini-satellite/CubeSat On-board processing Validation Experiment, or M-Cubed/COVE.


M-Cubed, developed in partnership with the University of Michigan, Ann Arbor, will image Earth. The COVE payload will use these data to validate an instrument image data processing algorithm that will greatly reduce the science data transmission rate required for on-orbit operations.


"The COVE payload will advance processor and algorithm technology designed for use in a future science instrument to characterize properties of aerosols and clouds, which will help our understanding of global climate change," said Paula Pingree of JPL, principal investigator of the MCubed/COVE-2 mission.


These technology validation missions are sponsored by NASA's Earth Science Technology Office. They are designed to satisfy their science objectives within six months, but will remain in Earth orbit for many years.


The California Institute of Technology in Pasadena manages JPL for NASA.
For additional information on NASA's CubeSat Launch Initiative program, visit: http://go.nasa.gov/nXOuPI .

David Israel 818-354-4797

Jet Propulsion Laboratory, Pasadena, Calif.

david.israel@jpl.nasa.gov


Joshua Buck 202-358-1100

NASA Headquarters, Washington

jbuck@nasa.gov


2013-353
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NASA Highlights Mars, Earth and Other Science at AGU Event

NASA Highlights Mars, Earth and Other Science at AGU Event:

An artist's concept of a solar-system montage featuring the eight planets, a comet and an asteroid.
An artist's concept of a solar-system montage featuring the eight planets, a comet and an asteroid. Image credit: NASA/JPL-Caltech
› Full image and caption


December 06, 2013

NASA researchers, including some from the Jet Propulsion Laboratory, will present new findings on a wide range of Earth and space science topics next week at the annual meeting of the American Geophysical Union (AGU).


The meeting will take place Dec. 9 to 13 at the Moscone Convention Center in San Francisco.


Some news conference will be available via live streaming at http://www.ustream.tv/nasajpl2, as follows:


Monday, 9 a.m. PSTCuriosity Rover Update

Monday, 10:30 a.m. PST Mapping Snowpack from the Sky

Tuesday, 9 a.m. PST Improving Natural Hazard Warnings

Tuesday, 10:30 a.m. PST News from Juno's Earth Flyby

Tuesday, 11:30 a.m. PST Dynamic Mars Over Time

Thursday, 11:30 a.m. PST New Results from Cassini Mission to Saturn


The briefings will not be carried on NASA Television.


After the Curiosity briefing on Dec. 9 hosted by AGU, a NASA media teleconference will be held at 10 a.m. PST (1 p.m. EST) to discuss the new results from the Radiation Assessment Detector on Curiosity. Audio will be streamed live on NASA's website at: http://www.nasa.gov/newsaudio .
NASA's media briefings during the meeting will feature topics such as the latest discoveries from Mars. Saturn's moon Titan, prospects for the recovery of the Antarctic ozone hole, Comet ISON, and close-up views of the sun from a NASA spacecraft launched this year.


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

Jia-Rui Cook 818-354-0850

Jet Propulsion Laboratory, Pasadena, Calif.

jccook@jpl.nasa.gov


Steve Cole 202-358-0918

NASA Headquarters, Washington

stephen.e.cole@nasa.gov


2013-352
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NASA Snow Mapper Reaps Big Benefits for California

NASA Snow Mapper Reaps Big Benefits for California:

Spatial distribution of snow water equivalent across the Tuolumne River Basin
Spatial distribution of snow water equivalent across the Tuolumne River Basin from April 10 to June 1, 2013 as measured by NASA's Airborne Snow Observatory. Image credit: NASA/JPL-Caltech
› Full image and caption


December 09, 2013

Unprecedented snowpack maps from NASA's prototype Airborne Snow Observatory mission helped water managers for 2.6 million residents of the San Francisco Bay Area achieve near-perfect water operations this summer, despite the driest year in California's recorded history.


The high-resolution NASA snow maps of the Tuolumne River Basin in the Sierra Nevada helped optimize reservoir filling and hydroelectric generation at the Hetch Hetchy reservoir and its O'Shaughnessy Dam. This resulted in a full reservoir at the end of the snowmelt season, no water spillage, and generation of more than $3.9 million in hydropower. The NASA data helped optimize operations during the last two critical weeks of runoff.


At a media briefing today at the American Geophysical Union meeting in San Francisco, scientists from NASA; the University of Washington, Seattle; and McGurk Hydrologic Associates, Orinda, Calif., discussed the observatory's first year of operations in California and the Uncompahgre watershed in Colorado's Upper Colorado River Basin. The three-year demonstration mission is a collaboration between NASA's Jet Propulsion Laboratory, Pasadena, Calif., and the California Department of Water Resources in Sacramento.


"For the first time, Airborne Snow Observatory data are telling us the total water in the snowpack in the watershed and the absorption of sunlight that control its melt speed, enabling us to estimate how much water will flow out of a basin when the snow melts," said Tom Painter, observatory principal investigator at JPL. "By combining near-real-time information on the total amount of water in the snowpack with observations of water inflow to Hetch Hetchy reservoir between April and July, we were able to greatly improve the model we developed to predict inflow into the reservoir."


Painter said this helped reservoir managers more efficiently allocate water inflow between power generation, water supplies and ecological purposes.


He noted that the improved snowpack measurements and more efficient reservoir operations are vital in the face of continued climate change, larger weather uncertainties, California's continuing severe drought and increasing demand for water.


Flying aboard a Twin Otter aircraft, the Airborne Snow Observatory measures two properties most critical to understanding snowmelt runoff and timing: snow depth and snow reflectivity. By combining snow depth with estimated density, snow water equivalent -- the amount of water in the snow -- is derived and used to calculate the amount of water that will run off. Snow reflectivity, or albedo, is the fraction of the incoming amount of sunlight reflected by snow. Subtracting reflected sunlight from incoming sunlight gives the absorbed sunlight, which largely controls the speed of snowmelt and timing of its runoff.


Before now, Tuolumne River Basin runoff forecasts could only be made using monthly manual ground snow surveys and daily automated measurement devices called snow pillows at sparsely located sites in lower to middle elevations. As those sites melt free of snow in early spring, an unknown amount of snow remains at higher elevations. The total area of the basin measured at all of these survey sites is only about 270 square feet (25 square meters). The observatory measured all the snow in the basin over an area 46 million times larger: 460 square miles (1,140 square kilometers).


The observatory mapped the basin weekly from early April through early June. Over 65 days, it measured the decline in water volume as the Hetch Hetchy basin snowpack melted, shrinking from 218.1 thousand acre-feet (71.06 billion gallons) to 15.2 thousand acre-feet (4.94 billion gallons). An acre-foot is the amount of water needed to cover an acre of land to a depth of one foot, or 325,851 gallons. For comparison, the average family of four uses about an acre-foot per year.


Every day in summer, 290 million gallons, or 870 acre-feet, come out of Hetch Hetchy and travel 150 miles (241 kilometers) to the San Francisco Peninsula, providing all or some of the water for 2.6 million customers. When full, the 8-mile-long (13-kilometer) reservoir holds 360.4 thousand acre-feet. The reservoir's water level is typically lowered about a third of the way (about 120 feet, or 37 meters) every summer.


In early June, a modeling forecast of predicted water inflow to the reservoir that had been corrected using Airborne Snow Observatory data was used to supplement the City of San Francisco's Hetch Hetchy Water & Power managers' existing models as they topped off the reservoir. Hydrologist Bruce McGurk of McGurk Hydrologic, Orinda, Calif., provided the results from a daily forecasting model he built to use with observatory results. Without the observatory data, his model over-predicted by 32,000 acre-feet the amount of water that would flow into the reservoir. Had all that water been used to generate power, it would have drafted the reservoir down 16 feet (4.9 meters) - water supplies that would not have been available to the thirsty city this summer. "The Airborne Snow Observatory provides information on snow depth and water quantity at weekly intervals that water managers have never had before, but have always wanted," McGurk said.


Beyond its water management applications, Associate Professor Jessica Lundquist of the University of Washington, Seattle, said the observatory data are game-changing in providing useful snow information for snow hydrology, climate sciences, glaciology and ecosystem studies. "Snow controls high-elevation streamflow and ecosystems, but we've historically had to guess how much snow fell and where it was stored," Lundquist said. "With these data, we can improve how we model mountain systems and predictions of how those systems will change in time. It's pretty amazing that we can both forecast for Hetch Hetchy and also drill down to one small basin affecting a meadow and see details that match photos taken on the ground. To me, the Airborne Snow Observatory snow maps are cooler than pictures from Mars."


"The Airborne Snow Observatory is an innovative use of NASA advanced sensor research applied to one of the top challenges our nation and our planet face: freshwater management and practical water management information needs," said Brad Doorn, program manager in Applied Sciences at NASA Headquarters in Washington. "The observatory is also advancing our scientific understanding of Earth processes and how we can better monitor them in the future, from both air and space."


JPL is a division of the California Institute of Technology in Pasadena. For more information on the Airborne Snow Observatory, visit: http://aso.jpl.nasa.gov/ .

Alan Buis 818-354-0474

Jet Propulsion Laboratory, Pasadena, Calif.

Alan.Buis@jpl.nasa.gov


2013-357
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NASA's Juno Gives Starship-Like View of Earth Flyby

NASA's Juno Gives Starship-Like View of Earth Flyby:

This cosmic pirouette of Earth and our moon was captured by the Juno spacecraft as it flew by Earth on Oct. 9, 2013.
This cosmic pirouette of Earth and our moon was captured by the Juno spacecraft as it flew by Earth on Oct. 9, 2013.
Image Credit: NASA/JPL-Caltech
› Larger image | 'HI' to Juno in Morse Code


December 10, 2013

When NASA's Juno spacecraft flew past Earth on Oct. 9, 2013, it received a boost in speed of more than 8,800 mph (about 3.9 kilometers per second), which set it on course for a July 4, 2016, rendezvous with Jupiter, the largest planet in our solar system. One of Juno's sensors, a special kind of camera optimized to track faint stars, also had a unique view of the Earth-moon system. The result was an intriguing, low-resolution glimpse of what our world would look like to a visitor from afar.


"If Captain Kirk of the USS Enterprise said, 'Take us home, Scotty,' this is what the crew would see," said Scott Bolton, Juno principal investigator at the Southwest Research Institute, San Antonio. "In the movie, you ride aboard Juno as it approaches Earth and then soars off into the blackness of space. No previous view of our world has ever captured the heavenly waltz of Earth and moon."


The Juno Earth flyby movie is available at: http://www.youtube.com/watch?v=_CzBlSXgzqI&feature=youtu.be . The music accompaniment is an original score by Vangelis.


The cameras that took the images for the movie are located near the pointed tip of one of the spacecraft's three solar-array arms. They are part of Juno's Magnetic Field Investigation (MAG) and are normally used to determine the orientation of the magnetic sensors. These cameras look away from the sunlit side of the solar array, so as the spacecraft approached, the system's four cameras pointed toward Earth. Earth and the moon came into view when Juno was about 600,000 miles (966,000 kilometers) away -- about three times the Earth-moon separation.


During the flyby, timing was everything. Juno was traveling about twice as fast as a typical satellite, and the spacecraft itself was spinning at 2 rpm. To assemble a movie that wouldn't make viewers dizzy, the star tracker had to capture a frame each time the camera was facing Earth at exactly the right instant. The frames were sent to Earth, where they were processed into video format.


"Everything we humans are and everything we do is represented in that view," said the star tracker's designer, John Jørgensen of the Danish Technical University, near Copenhagen.


Also during the flyby, Juno's Waves instrument, which is tasked with measuring radio and plasma waves in Jupiter's magnetosphere, recorded amateur radio signals. This was part of a public outreach effort involving ham radio operators from around the world. They were invited to say "HI" to Juno by coordinating radio transmissions that carried the same Morse-coded message. Operators from every continent, including Antarctica, participated. The results can be seen in this video clip: http://www.jpl.nasa.gov/video/?id=1263 . A four-minute video depicting the efforts of a few of the amateur radio operators who participated in the event can be seen at: http://www.jpl.nasa.gov/video/?id=1262


"With the Earth flyby completed, Juno is now on course for arrival at Jupiter on July 4, 2016," said Rick Nybakken, Juno project manager at NASA's Jet Propulsion Laboratory in Pasadena, Calif.


The Juno spacecraft was launched from Kennedy Space Center in Florida on August 5, 2011. Juno's launch vehicle was capable of giving the spacecraft only enough energy to reach the asteroid belt, at which point the sun's gravity pulled it back toward the inner solar system. Mission planners designed the swing by Earth as a gravity assist to increase the spacecraft's speed relative to the sun, so that it could reach Jupiter. (The spacecraft's speed relative to Earth before and after the flyby is unchanged.)


After Juno arrives and enters into orbit around Jupiter in 2016, the spacecraft will circle the planet 33 times, from pole to pole, and use its collection of science instruments to probe beneath the gas giant's obscuring cloud cover. Scientists will learn about Jupiter's origins, internal structure, atmosphere and magnetosphere.


Juno's name comes from Greek and Roman mythology. The god Jupiter drew a veil of clouds around himself to hide his mischief from his wife, but the goddess Juno used her special powers to peer through the clouds and reveal Jupiter's true nature.


NASA's Jet Propulsion Laboratory, Pasadena, Calif., manages the Juno mission for the principal investigator, Scott Bolton, of Southwest Research Institute in San Antonio. The Juno mission is part of the New Frontiers Program managed at NASA's Marshall Space Flight Center in Huntsville, Ala. Lockheed Martin Space Systems, Denver, built the spacecraft. JPL is a division of the California Institute of Technology in Pasadena.


More information about Juno is online at:
http://www.nasa.gov/juno and http://missionjuno.swri.edu

DC Agle 818-393-9011

Jet Propulsion Laboratory, Pasadena, Calif.

agle@jpl.nasa.gov


Steve Cole 202-358-0918

NASA Headquarters, Washington

Stephen.e.cole@nasa.gov


2013-360
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Clay-Like Minerals Found on Icy Crust of Europa

Clay-Like Minerals Found on Icy Crust of Europa:

This image, using data from NASA's Galileo mission, shows the first detection of clay-like minerals on the surface of Jupiter's moon Europa
This image, using data from NASA's Galileo mission, shows the first detection of clay-like minerals on the surface of Jupiter's moon Europa. Image credit: NASA/JPL-Caltech/SETI
› Full image and caption


December 11, 2013

A new analysis of data from NASA's Galileo mission has revealed clay-type minerals at the surface of Jupiter's icy moon Europa that appear to have been delivered by a spectacular collision with an asteroid or comet. This is the first time such minerals have been detected on Europa's surface. The types of space rocks that deliver such minerals typically also often carry organic materials.


"Organic materials, which are important building blocks for life, are often found in comets and primitive asteroids," said Jim Shirley, a research scientist at NASA's Jet Propulsion Laboratory, Pasadena, Calif. Shirley is giving a talk on this topic at the American Geophysical Union meeting in San Francisco on Friday, Dec. 13. "Finding the rocky residues of this comet crash on Europa's surface may open up a new chapter in the story of the search for life on Europa," he said.


Many scientists believe Europa is the best location in our solar system to find existing life. It has a subsurface ocean in contact with rock, an icy surface that mixes with the ocean below, salts on the surface that create an energy gradient, and a source of heat (the flexing that occurs as it gets stretched and squeezed by Jupiter's gravity). Those conditions were likely in place shortly after Europa first coalesced in our solar system.


Scientists have also long thought there must be organic materials at Europa, too, though they have yet to detect them directly. One theory is that organic material could have arrived by comet or asteroid impacts, and this new finding supports that idea.


Shirley and colleagues, funded by a NASA Outer Planets Research grant, were able to see the clay-type minerals called phyllosilicates in near-infrared images from Galileo taken in 1998. Those images are low resolution by today's standards, and Shirley's group is applying a new technique for pulling a stronger signal for these materials out of the noisy picture. The phyllosilicates appear in a broken ring about 25 miles (40 kilometers) wide, which is about 75 miles (120 kilometers) away from the center of a 20-mile-diameter (30 kilometers) central crater site.


The leading explanation for this pattern is the splash back of material ejected when a comet or asteroid hits the surface at an angle of 45 degrees or more from the vertical direction. A shallow angle would allow some of the space rock's original material to fall back to the surface. A more head-on collision would likely have vaporized it or driven that space rock's materials below the surface. It is hard to see how phyllosilicates from Europa's interior could make it to the surface, due to Europa's icy crust, which scientists think may be up to 60 miles (100 kilometers) thick in some areas.


Therefore, the best explanation is that the materials came from an asteroid or comet. If the body was an asteroid, it was likely about 3,600 feet (1,100 meters) in diameter. If the body was a comet, it was likely about 5,600 feet (1,700 meters) in diameter. It would have been nearly the same size as the comet ISON before it passed around the sun a few weeks ago.


"Understanding Europa's composition is key to deciphering its history and its potential habitability," said Bob Pappalardo of JPL, the pre-project scientist for a proposed mission to Europa. "It will take a future spacecraft mission to Europa to pin down the specifics of its chemistry and the implications for this moon hosting life."


For more information about Europa, visit: http://solarsystem.nasa.gov/europa/home.cfm .


JPL is a division of the California Institute of Technology in Pasadena.

Jia-Rui C. Cook 818-354-0850

Jet Propulsion Laboratory, Pasadena, Calif.

jccook@jpl.nasa.gov


2013-362
Posted by Nelio Inacio at 5:03 PM 0 comments
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Hubble Sees Evidence of Water Vapor at Jupiter Moon

Hubble Sees Evidence of Water Vapor at Jupiter Moon:

This is an artist's concept of a plume of water vapor thought to be ejected off the frigid, icy surface of the Jovian moon Europa
This is an artist's concept of a plume of water vapor thought to be ejected off the frigid, icy surface of the Jovian moon Europa, located about 500 million miles (800 million kilometers) from the sun. Image credit: NASA/ESA/K. Retherford/SWRI
› Full image and caption


December 12, 2013

NASA's Hubble Space Telescope has observed water vapor above the frigid south polar region of Jupiter's moon Europa, providing the first strong evidence of water plumes erupting off the moon's surface.


Previous scientific findings from other sources already point to the existence of an ocean located under Europa's icy crust. Researchers are not yet fully certain whether the detected water vapor is generated by erupting water plumes on the surface, but they are confident this is the most likely explanation.


Should further observations support the finding, this would make Europa the second moon in the solar system known to have water vapor plumes. The findings are being published in the Dec. 12 online issue of Science Express, and reported at the meeting of the American Geophysical Union in San Francisco.


"By far the simplest explanation for this water vapor is that it erupted from plumes on the surface of Europa," said lead author Lorenz Roth of Southwest Research Institute in San Antonio. "If those plumes are connected with the subsurface water ocean we are confident exists under Europa's crust, then this means that future investigations can directly investigate the chemical makeup of Europa's potentially habitable environment without drilling through layers of ice. And that is tremendously exciting."


In 2005, NASA's Cassini orbiter detected jets of water vapor and dust spewing off the surface of Saturn's moon Enceladus. Although ice and dust particles have subsequently been found in the Enceladus plumes, only water vapor gases have been measured at Europa so far.


Hubble spectroscopic observations provided the evidence for Europa plumes in December 2012. Time sampling of Europa's auroral emissions measured by Hubble's imaging spectrograph enabled the researchers to distinguish between features created by charged particles from Jupiter's magnetic bubble and plumes from Europa's surface, and also to rule out more exotic explanations such as serendipitously observing a rare meteorite impact.


The imaging spectrograph detected faint ultraviolet light from an aurora, powered by Jupiter's intense magnetic field, near the moon's south pole. Excited atomic oxygen and hydrogen produce a variable auroral glow and leave a telltale sign that are the products of water molecules being broken apart by electrons along magnetic field lines.


"We pushed Hubble to its limits to see this very faint emission. These could be stealth plumes, because they might be tenuous and difficult to observe in the visible light," said Joachim Saur of the University of Cologne, Germany. Saur, who is principal investigator of the Hubble observation campaign, co-wrote the paper with Roth.


Roth suggested that long cracks on Europa's surface, known as lineae, might be venting water vapor into space. Cassini has seen similar fissures that host the Enceladus jets.


Also the Hubble team found that the intensity of the Europa plumes, like those at Enceladus, varies with Europa's orbital position. Active jets have only been seen when the moon is farthest from Jupiter. The researchers could not detect any sign of venting when Europa is closer to Jupiter.


One explanation for the variability is that these lineae experience more stress as gravitational tidal forces push and pull on the moon and open vents at larger distances from Jupiter. The vents are narrowed or closed when the moon is closest to the gas-giant planet.


"The apparent plume variability supports a key prediction that Europa should tidally flex by a significant amount if it has a subsurface ocean," said Kurt Retherford, also of Southwest Research Institute.


The Europa and Enceladus plumes have remarkably similar abundances of water vapor. Because Europa has a roughly 12 times stronger gravitational pull than Enceladus, the minus-40-degree-Fahrenheit (minus-40-degree-Celsius) vapor for the most part doesn't escape into space as it does at Enceladus, but rather falls back onto the surface after reaching an altitude of 125 miles (201 kilometers), according to the Hubble measurements. This could leave bright surface features near the moon's south polar region, the researchers hypothesize.


"If confirmed, this new observation once again shows the power of the Hubble Space Telescope to explore and opens a new chapter in our search for potentially habitable environments in our solar system," said John Grunsfeld, an astronaut who participated Hubble servicing missions and now serves as NASA's associate administrator for science in Washington. "The effort and risk we took to upgrade and repair Hubble becomes all the more worthwhile when we learn about exciting discoveries like this one from Europa."


The Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency. NASA's Goddard Space Flight Center manages the telescope. The Space Telescope Science Institute (STScI) conducts Hubble science operations. STScI is operated for NASA by the Association of Universities for Research in Astronomy, Inc., in Washington, D.C.


To view the images of the evidence for plumes visit: http://www.nasa.gov/content/goddard/hubble-europa-water-vapor .
For more information about the Hubble Space Telescope, visit: http://www.nasa.gov/hubble .

Jia-Rui C. Cook 818-354-0850

Jet Propulsion Laboratory, Pasadena, Calif.

jccook@jpl.nasa.gov


Rob Gutro 301-286-4044

Goddard Space Flight Center

robert.j.gutro@nasa.gov


Dwayne Brown/J.D. Harrington

Headquarters, Washington

202-358-1726/202-358-5241

dwayne.c.brown@nasa.gov, j.d.harrington@nasa.gov


Joe Fohn

Southwest Research Institute, San Antonio

210-522-4630

jfohn@swri.org


2013-363
Posted by Nelio Inacio at 5:03 PM 0 comments

Chemical Surprise Found in Crab Nebula

Chemical Surprise Found in Crab Nebula:

This image shows a composite view of the Crab nebula, an iconic supernova remnant in our Milky Way galaxy, as viewed by the Herschel Space Observatory and the Hubble Space Telescope
This image shows a composite view of the Crab nebula, an iconic supernova remnant in our Milky Way galaxy, as viewed by the Herschel Space Observatory and the Hubble Space Telescope. Image credit: ESA/Herschel/PACS/MESS Key Programme Supernova Remnant Team; NASA, ESA and Allison Loll/Jeff Hester (Arizona State University)
› Full image and caption


December 12, 2013

Astronomers have discovered a rare chemical pairing in the remains of an exploded star, called the Crab nebula. A gas thought to be a loner has made a "friend," linking up with a chemical partner to form a molecule. The discovery, made with the Herschel space observatory, a European Space Agency mission with important NASA contributions, will help scientists better understand supernovas, the violent deaths of massive stars.


The unexpected find involves a noble gas called Argon, named for its chemical aloofness after the Greek word for "inactive." Noble gases, which also include helium and neon among others, rarely engage in chemical reactions. They prefer to go it alone.


A new study, led by Michael Barlow from University College London, United Kingdom, and based on spectral data from Herschel, has found the first evidence of such a noble gas-based compound in space, a molecule called argon hydride. The results are published in the journal Science.


"The strange thing is that it is the harsh conditions in a supernova remnant that seem to be responsible for some of the argon finding a partner with hydrogen," said Paul Goldsmith of NASA's Jet Propulsion Laboratory, Pasadena, Calif.


"This is not only the first detection of a noble-gas based molecule in space, but also a new perspective on the Crab nebula. Herschel has directly measured the argon isotope we expect to be produced via explosive nucleosynthesis in a core-collapse supernova, refining our understanding of the origin of this supernova remnant," concludes Göran Pilbratt, Herschel project scientist at the European Space Agency.


Read the full ESA news release at:

http://sci.esa.int/herschel/53332-herschel-spies-active-argon-in-crab-nebula/ .


Herschel is a European Space Agency mission, with science instruments provided by consortia of European institutes and with important participation by NASA. 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 United States 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


2013-365
Posted by Nelio Inacio at 5:02 PM 0 comments

Surprise Picture for WISE's Fourth Anniversary

Surprise Picture for WISE's Fourth Anniversary:

March of Asteroids Across Dying Star
A dying star, called the Helix nebula, is shown surrounded by the tracks of asteroids in an image captured by NASA's Wide-field Infrared Survey Explorer, or WISE. Image credit: NASA/JPL-Caltech/UCLA
› Full image and caption

December 12, 2013

In an unexpected juxtaposition of cosmic objects that are actually quite far from each other, a newly released image from NASA's Wide-Field Infrared Survey Explorer (WISE) shows a dying star, called the Helix nebula, surrounded by the tracks of asteroids. The nebula is far outside our solar system, while the asteroid tracks are inside our solar system.


The portrait, discovered by chance in a search for asteroids, comes at a time when the mission's team is celebrating its fourth launch anniversary -- and new lease on life. In August, NASA decided to bring WISE out of hibernation to search for more asteroids. The mission was rechristened NEOWISE, formerly the name of the asteroid-hunting portion of WISE.


"I was recently looking for asteroids in images collected in 2010, and this picture jumped out at me," said Amy Mainzer, the NEOWISE principal investigator at NASA's Jet Propulsion Laboratory, Pasadena, Calif. "I recognized the Helix nebula right away."


WISE launched into the morning skies above Vandenberg Air Force Base in central California on Dec. 14, 2009. By early 2011, it had finished scanning the entire sky twice in infrared light, snapping pictures of nearly one billion objects, including remote galaxies, stars and asteroids. Upon completing its main goals, WISE was put to sleep. Now, engineers are bringing the spacecraft out of slumber, as it cools back down to the chilly temperatures required for infrared observations. The spacecraft no longer has onboard coolant, but two of its infrared channels still work and can be used for asteroid hunting.


"WISE is the spacecraft that keeps on giving," said Ned Wright of UCLA, the principal investigator of WISE before it transitioned into NEOWISE.


In the Helix nebula image, infrared wavelengths of light have been assigned different colors, with longer wavelengths being red, and shorter, blue. The bluish-green and red materials are expelled remnants of what was once a star similar to our sun. As the star aged, it puffed up and its outer layers sloughed off. The burnt-out core of the star, called a white dwarf, is heating the expelled material, inducing it to glow with infrared light. Over time, the brilliant object, known as a planetary nebula, will fade away, leaving just the white dwarf.


Skirting around the edges of the Helix nebula are the footprints of asteroids marching across the field of view. Each set of yellow dots is a series of pictures of an asteroid. As the asteroid moved, WISE snapped several pictures, all of which are represented in this view. Scientists use these data to discover and characterize asteroids, including those that pass relatively close to Earth, called near-Earth asteroids. Infrared data are particularly useful for finding the smaller, darker asteroids that are more difficult to see with visible light, and for measuring the asteroids' sizes.


The other streaks in the picture are Earth-orbiting satellites and cosmic rays.


JPL manages and operates NEOWISE 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 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://neowise.ipac.caltech.edu, http://www.nasa.gov/wise and http://wise.astro.ucla.edu .

Whitney Clavin 818-354-4673

Jet Propulsion Laboratory, Pasadena, Calif.

whitney.clavin@jpl.nasa.gov


2013-366
Posted by Nelio Inacio at 5:02 PM 0 comments

New Animals on Display at Spitzer's Citizen Science Zoo

New Animals on Display at Spitzer's Citizen Science Zoo:

A screen shot from the Milky Way Project illustrates how users are asked to catalog objects in our galaxy.
A screen shot from the Milky Way Project illustrates how users are asked to catalog objects in our galaxy. Image credit: Zooniverse
› Larger image


December 16, 2013

Since 2010, about 50,000 volunteers have taken to their computers to help astronomers catalog star-blown bubbles captured in images from NASA's Spitzer Space Telescope. Their efforts resulted in several scientific papers, and a deeper understanding of our Milky Way galaxy and its frothy star-forming clouds.


Now, an updated version of the campaign, called the Milky Way Project, is releasing more images with a whole new set of "animals" to track in the cosmic zoo. Volunteers are asked to catalog a host of objects, including towering pillars of dust, bow shocks rammed into cosmic dust by speeding stars and even other galaxies hiding behind dust.


"Spitzer has made a hugely detailed survey of our galaxy so expansive you can't take it all in at once," said Robert Hurt, an imaging specialist at NASA's Spitzer Science Center at the California Institute of Technology, Pasadena, Calif. "This project guarantees that every pixel will be seen by many people. No corner will go unexplored."


The Milky Way Project is part of the Zooniverse group, a collection of online citizen science activities. The idea is to recruit volunteers from all walks of life, all over the world, to help tackle big science problems, and learn something in the process.


The Spitzer images were taken as part of the mission's GLIMPSE project, which stands for Galactic Legacy Infrared Mid-Plane Survey Extraordinaire. GLIMPSE and its follow-up surveys have mapped out a strip of sky all around us, covering most of our Milky Way galaxy. Spitzer's infrared vision allows it to cut through the dust, unveiling cosmic creatures that remain unseen in visible-light views.


If you'd like to join the cosmic safari, visit: http://www.milkywayproject.org .


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. Spacecraft operations are based at Lockheed Martin Space Systems Company, Littleton, Colo. 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


2013-368
Posted by Nelio Inacio at 5:02 PM 0 comments

Dawn Creates Guide to Vesta's Hidden Attractions

Dawn Creates Guide to Vesta's Hidden Attractions:

Flowing in, Flowing out of Aelia
This colorful composite image from NASA's Dawn mission shows the flow of material inside and outside a crater called Aelia on the giant asteroid Vesta. The area is around 14 degrees south latitude. The images that went into this composite were obtained by Dawn's framing camera from September to October 2011. Image credit: NASA/JPL-Caltech/UCLAMPS/DLR/IDA
› Full image and caption


December 16, 2013

Some beauty is revealed only at a second glance. When viewed with the human eye, the giant asteroid Vesta, which was the object of scrutiny by the Dawn spacecraft from 2011 to 2012, is quite unspectacular color-wise. Vesta looks grayish, pitted by a variety of large and small craters.


But scientists at the Max Planck Institute for Solar System Research in Katlenburg-Lindau, Germany, have re-analyzed the images of this giant asteroid obtained by Dawn's framing camera. They assigned colors to different wavelengths of light and, in the process, revealed in unprecedented detail not only geological structures that are invisible to the naked eye, but also landscapes of incomparable beauty.


Researchers at Max Planck can now see structures such as melts from impacts, craters buried by quakes and foreign material brought by space rocks, visible with a resolution of 200 feet (60 meters) per pixel.


"The key to these images is the seven color filters of the camera system on board the spacecraft," said Andreas Nathues, the framing camera team lead at Max Planck. Since different minerals reflect light of different wavelengths to different degrees, the filters help reveal compositional differences that remain hidden without them. In addition, scientists calibrated the data so that the finest variations in brightness can be seen.


In the new colorized images, different colors indicate different materials on the surface of Vesta. They reveal impressive formations and a wide range of geological diversity, said Nathues. But above all, the color-coded images are impressive because of their beauty.


"No artist could paint something like that. Only nature can do this," said Martin Hoffman, a member of the framing camera team also at Max Planck. Pictures of the crater Aelia, the crater Antonia and an area near the crater Sextilia show some of Vesta's most impressive sites.


Dawn visited Vesta from July 2011 to September 2012. The spacecraft is currently on its way to its second destination, the dwarf planet Ceres. Ceres is the largest object in the main asteroid belt between Mars and Jupiter.


The Dawn mission to Vesta and Ceres is managed by NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, for NASA's Science Mission Directorate, Washington. UCLA is responsible for overall Dawn mission science. The Dawn framing cameras were developed and built under the leadership of the Max Planck Institute for Solar System Research, Katlenburg-Lindau, Germany, with significant contributions by DLR German Aerospace Center, Institute of Planetary Research, Berlin, and in coordination with the Institute of Computer and Communication Network Engineering, Braunschweig. The framing camera project is funded by the Max Planck Society, DLR and NASA.


More information on Dawn is available at: http://www.nasa.gov/dawn and http://dawn.jpl.nasa.gov .

Jia-Rui Cook 818-354-0850

Jet Propulsion Laboratory, Pasadena, Calif.

jccook@jpl.nasa.gov


Birgit Krummheuer +49 5556-979-462

Max Planck Institute for Solar System Research, Katlenburg-Lindau, Germany

presse@mps.mpg.de


2013-367
Posted by Nelio Inacio at 5:01 PM 0 comments

NASA's Deep Space Network Turns 50

NASA's Deep Space Network Turns 50:

Dawn in the Apollo Valley
Beam Wave Guide antennas at Goldstone, known as the "Beam Waveguide Cluster." Each antenna is 111.5-feet (34-m) in diameter. They're located in an area at Goldstone called "Apollo Valley." This photograph was taken on Jan. 11, 2012. Credit: NASA/JPL-Caltech › Full image and caption


December 18, 2013

NASA's Deep Space Network, the world's largest and most powerful communications system for "talking to" spacecraft, will reach a milestone on Dec. 24: the 50th anniversary of its official creation.


Over the past 50 years, antennas of the Deep Space Network (DSN) have communicated with just about every mission that has gone to the moon or beyond. The historic communiqués include "That's one small step for man. One giant leap for mankind"; numerous encounters with the outer planets of our solar system; images taken by rovers exploring Mars; and the data confirming that NASA's Voyager spacecraft had finally entered interstellar space.


The Deep Space Network has been so critical to so many missions over the decades, the network's team members like to use the phrase "Don't leave Earth without us."


From the very beginning of NASA's space program, it was clear that a simple, direct way to communicate with missions in deep space would be needed. For example, what is the purpose of sending a spacecraft to Mars if we can't receive data, images and other vital information from that spacecraft?


More information about the Deep Space Network is online at:

http://www.jpl.nasa.gov/dsn50/


What is now known as the Deep Space Network first existed as just a few small antennas called the Deep Space Instrumentation Facility. The facility was originally operated by the U.S. Army in the 1950s and then later moved over to the jurisdiction of the newly created National Aeronautics and Space Administration (NASA).


On December 24, 1963, the Deep Space Instrumentation Facility officially morphed into the Deep Space Network and quickly became the de facto network for any planned missions into deep space. Three antenna complexes were established around the globe, spread out at roughly 120 degrees of longitude so that even as Earth rotated, spacecraft would always be above the horizon of at least one complex. While some of the communication facilities have moved over the decades, today the three complexes, which operate 24/7/365, are located in Canberra, Australia; Madrid, Spain; and Goldstone, Calif.


Space agencies in Europe, Japan and Russia have all relied on the Deep Space Network when planning and communicating with their own missions over the decades. The Deep Space Network has been used recently by India's first interplanetary probe, the Mars Orbiter Mission (MOM).


"Today, the DSN supports a fleet of more than 30 U.S. and international robotic space missions," said DSN Project Manager Al Bhanji of NASA's Jet Propulsion Laboratory, Pasadena, Calif., which manages the Deep Space Network. "Without the DSN, we would never have been able to undertake voyages to Mercury and Venus, visit asteroids and comets, we'd never have seen the stunning images of robots on Mars, or close-up views of the majestic rings of Saturn."


In addition to allowing missions to upload and download data to and from dozens of spacecraft, the network helps navigators pinpoint spots for landings and conduct burns that place spacecraft into orbit around other planets, or fine-tune their trajectory. Currently, the list of spacecraft supported by the DSN includes NASA's Curiosity rover on Mars, the Spitzer Space Telescope, the Saturn explorer Cassini and the two Voyager spacecraft, which are more than 9.6 billion miles (15.5 billion kilometers) away from Earth.


The Deep Space Network is also instrumental in carrying out its own science investigations. For instance, the 230-foot (70-meter) antenna at Goldstone is capable of using its radar to "ping" the near-Earth asteroids to determine a highly accurate position and velocity, and scientists are then able to calculate trajectories the asteroids will take over the next 100 years or more. This is crucial for tracking asteroids that could potentially cause damage were they to impact Earth. If the asteroid is close enough, they can also use the radar to "image" the objects to determine its size, shape and rotation.


Additionally, by combining signals from the DSN antennas with other radio telescopes in an appropriate manner, one can create a "synthetic telescope" that's able to peer into the cores of active galaxies halfway across the observable universe. Likewise, the DSN can be used to probe interiors of planets in our own galaxy, study the solar wind and study gravitational physics.


The future of the Deep Space Network looks bright, with optical communications on the horizon to augment the traditional RF-technology (radio waves moving at the speed of light). Optical communications, when operational, will provide a dramatic increase in data return from science missions; the potential bandwidth carried by an optical communications laser beam is far greater than with traditional radio frequencies. In fact, the DSN team envisions the day, not so far off, when, in addition to returning photos of robotic wheel tracks in the dusty surface of Mars, they will be streaming video to a wide-eyed public as the first humans leave their own footprints on its surface.


"In 2063, when we celebrate the Deep Space Network's 100th anniversary, we can imagine that we might be recalling the amazing days when our antennas streamed high-res video as the first humans stepped onto the surface of Mars," said Al Bhanji. "Or that day when we discovered a new living 'Earth' orbiting a distant star."


Of course, no one knows if or when that day might come. But the DSN will likely play a paramount role in breaking the "Earth-shattering" news.


JPL, a division of the California Institute of Technology in Pasadena, manages the Deep Space Network for NASA.


More information about NASA's Space Communications and Navigation program is at:


http://www.spacecomm.nasa.gov

David Israel 818-354-4797

Jet Propulsion Laboratory, Pasadena, Calif.

david.israel@jpl.nasa.gov


Joshua Buck 202-358-1100

NASA Headquarters, Washington

jbuck@nasa.gov


2013-370
Posted by Nelio Inacio at 5:01 PM 0 comments

The Rise and Fall of Galactic Cities

The Rise and Fall of Galactic Cities:

Galactic Metropolis
The collection of red dots seen near the center of this image show one of several very distant galaxy clusters discovered by combining ground-based optical data from the National Optical Astronomy Observatory's Kitt Peak National Observatory with infrared data from NASA's Spitzer Space Telescope. This galaxy cluster, named ISCS J1434.7+3519, is located about 9 billion light-years from Earth. Image credit: NASA/JPL-Caltech/KPNO/University of Missouri-Kansas City
› Full image and caption


December 18, 2013

In the fable of the town and country mice, the country mouse visits his city-dwelling cousin to discover a world of opulence. In the early cosmos, billions of years ago, galaxies resided in the equivalent of urban or country environments. Those that dwelled in crowded areas called clusters also experienced a kind of opulence, with lots of cold gas, or fuel, for making stars.


Today, however, these galactic metropolises are ghost towns, populated by galaxies that can no longer form stars. How did they get this way and when did the fall of galactic cities occur?


A new study from NASA's Spitzer Space Telescope finds evidence that these urban galaxies, or those that grew up in clusters, dramatically ceased their star-making ways about 9 billion years ago (our universe is 13.8 billion years old). These galactic metropolises either consumed or lost their fuel. Galaxies in the countryside, by contrast, are still actively forming stars.


"We know the cluster galaxies we see around us today are basically dead, but how did they get that way?" wondered Mark Brodwin of the University of Missouri-Kansas City, lead author of this paper, published in the Astrophysical Journal. "In this study, we addressed this question by observing the last major growth spurt of galaxy clusters, which happened billions of years ago."


Researchers studying distant galaxies get a peek into the past since the galaxies' light takes time, sometimes billions of years, to reach us. Brodwin and his colleagues used Spitzer to study 16 galaxy clusters that existed between the time our universe was 4.3 and 6 billion years old. Spitzer's infrared vision allows it see the dust warmed by new stars, revealing star-formation rates. NASA's Hubble Space Telescope and the W.M. Keck Observatory were used to measure the galaxies' distances from Earth.


This is one of the most comprehensive looks at distant galaxy clusters yet, revealing new surprises about their environments. Previous observations of relatively nearby clusters suggested that the urban, cluster galaxies produced all their stars early in the history of our universe in one big burst. This theory, called monolithic collapse, predicted that these tight-knit galaxies would have used all their fuel at once in an early, youthful frenzy. But the new study shows this not to be the case: The urban galaxies continued to make stars longer than expected, until suddenly production came to a halt around 9 billion years ago, or about 3 billion years later than previously thought.


A second study using observations from the Herschel Space Observatory, led by Stacey Alberts at the University of Massachusetts-Amherst and published in the Monthly Notices of the Royal Astronomical Society journal, finds a similar transition epoch. Alberts and colleagues observed 300 clusters over a longer period of time, dating back to when the universe was 4 to 10 billion years old. Herschel, which ran out of coolant in April of 2013 as expected, detected longer wavelengths of infrared light than Spitzer, which is still up and running. The two telescopes complement each other, allowing scientists to confirm results and probe different aspects of cosmic conundrums.


"We find that around 9 billion years ago, cluster galaxies were as active as their counterparts outside of clusters; however, their rate of star formation decreases dramatically between then and now, much more quickly than we see in isolated galaxies," said Alberts.


Why do the urban galaxies shut down their star formation sooner and more rapidly than the country bumpkins? Brodwin says this may have to do with galaxy mergers. The more crowded a galactic environment, as is the case in young, growing galaxy clusters, the more often two galaxies will collide and merge. Galaxy mergers induce bursts of fuel-consuming star formation, and also feed growing supermassive black holes, which then blast out radiation that heats up the gas and quickly shuts off the star formation.


"It's as if boom times for galaxies in clusters ended with a sudden widespread collapse," said Peter Eisenhardt of NASA's Jet Propulsion Laboratory, Pasadena, Calif., who led a previous study that identified the distant galaxy cluster sample used by Brodwin and Alberts. "They go from vibrantly forming new stars to the quiescent state they've been in for the last half of the history of the universe, and the switch happens surprisingly fast."


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. 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


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