NASA/JPL

New NASA Web Portal Shines Beacon on Rising Seas

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Fort Lauderdale, Florida, is at risk from rising sea levels. Credit: Dave/Flickr Creative Commons/CC BY 2.0

 

Sea level rise is a critical global issue affecting millions across our planet. A new Web portal developed by NASA’s Jet Propulsion Laboratory, Pasadena, California, gives researchers, decision makers and the public alike a resource to stay up to date with the latest developments and scientific findings in this rapidly advancing field of study. 

The portal, “Sea Level Change: Observations from Space,” is online at: https://sealevel.nasa.gov/

The portal’s key features include:
 

  • “Understanding Sea Level,” a summary of decades of scientific research that has shaped our knowledge of sea level rise: its causes, including a warming, expanding ocean and melting ice on land; projections of future sea level rise; and ways in which humanity might adapt, largely drawn from NASA data.
     
  • An interactive data analysis tool, launching in mid-2016, that will allow direct access to NASA datasets on sea level. Users will be able to manipulate these datasets to automatically generate charts, graphs and maps of sea surface height, temperature and other factors. The analysis tool will also allow users to make forecasts of future conditions, as well as “hindcasts” — retroactive calculations of past trends and conditions.
     
  • News highlights and feature stories with strong visual elements that explore the findings of sea level researchers in detail.
     
  • An extensive library of published papers on sea level-related topics, hyperlinked to individual citations throughout “Understanding Sea Level.”
     
  • A multimedia section with dynamic still and video imagery, and a glossary of sea level terms.

  • A “frequently asked questions” section maintained by sea level scientists. Users can submit questions to scientists and data managers.


The website is optimized for most mobile devices, including smartphones and tablets.

“Sea Level Change: Observations from Space” is managed by a team led by JPL scientist Carmen Boening. The team is part of the NASA Sea Level Change Team research group. 

“With sea levels rising globally, as observed by satellites over the past decades, sea level change is a hot topic in climate research,” Boening said. “This new tool provides a NASA resource for researchers and a wealth of information for members of the public seeking a deeper understanding of sea level change.”

For more information on NASA’s Earth science activities, visit: http://www.nasa.gov/earth and http://climate.nasa.gov

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

 

 

 

 

 

Media Invited to See NASA’s Orion Crew Module for its Journey to Mars

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January 20, 2016
MEDIA ADVISORY M16-005

*** NOTE: Press release are usually published under that page “Media Releases (Information for Journalist).” These press releases are usually meetings or presentation of studies. The public will most of the time have access to view or listen to most of these, but only credentialed media can ask question.

Also, before the meeting documentation may be made available, sometimes weeks before the meeting. If the documents are embargoed, we in the press know that means the information cannot be published before the embargo date and time. We use the time to pre-write our stories and prepare questions, but the embargo must be honored by all.

–  George McGinn, Examining Life (And Things of Interest), Daily Defense News and Cosmology and Space Exploration news websites.


Orion’s pressure vessel was completed Jan. 13, 2016 at NASA’s Michoud Assembly Facility in New Orleans. The pressure vessel is the spacecraft’s underlying structure on which all of the spacecraft’s systems and subsystems are built and integrated. (Credit: NASA)

 

NASA’s Orion crew module will be available to media at two NASA locations Jan. 26th and in early February, as engineers continue to prepare the spacecraft to send astronauts deeper into space than ever before, including to an asteroid placed in lunar orbit and on the journey to Mars.

At 10:30 a.m. EST on Tuesday, Jan. 26, the agency’s Michoud Assembly Facility in New Orleans will host a media viewing and facility tour of the spacecraft’s recently completed pressure vessel, the underlying structure of the crew module, before it ships to NASA’s Kennedy Space Center in Florida.

To attend the event at Michoud, reporters must contact Chip Howat at 504-257-0478 or carl.j.howat@nasa.gov by 3 p.m. Monday, Jan. 25. International media accreditation for this event is closed.

The Orion pressure vessel provides a sealed environment for astronaut life support in future human-rated crew modules. Technicians at Michoud began welding together the seven large aluminum pieces of Orion’s primary structure in precise detail last September. At Kennedy, Orion will be outfitted with the spacecraft’s systems and subsystems, processed and integrated with NASA’s Space Launch System (SLS) ahead of their first joint exploration mission, or EM-1.

Michoud also is where the massive core stage of SLS is being manufactured. Reporters will be able to view tooling and newly manufactured hardware for SLS, and hear about mission progress from personnel across NASA.

Individuals available for interviews during the tour include:

  • Bill Hill, deputy associate administrator for Exploration Systems Development at NASA Headquarters in Washington
  • Mike Sarafin, EM-1 mission manager at NASA Headquarters
  • Mark Kirasich, Orion program manager at NASA’s Johnson Space Center in Houston
  • Scott Wilson, Orion production manager at Kennedy
  • John Honeycutt, SLS program manager at the agency’s Marshall Space Flight Center in Huntsville, Alabama
  • Steve Doering, SLS core stage manager at Marshall
  • Mike Bolger, Ground Systems Development and Operations program manager at Kennedy
  • NASA astronaut Rick Mastracchio
  • Mike Hawes, Orion program manager for Lockheed Martin
  • Jim Bray, crew module director for Lockheed Martin 

Orion will depart Michoud on or about Feb. 1 and travel to Kennedy aboard NASA’s Super Guppy airplane. Additional details for Orion’s arrival at Kennedy, including media accreditation, are forthcoming.

For more information about Orion, visit: http://www.nasa.gov/orion

-end- 

 

NASA Spots the ‘Great Pumpkin’: Halloween Asteroid a Treat for Radar Astronomers

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This is a graphic depicting the orbit of asteroid 2015 TB145. The asteroid will safely fly past Earth slightly farther out than the moon’s orbit on Oct. 31 at 10:05 a.m. Pacific (1:05 p.m. EDT and 17:05 UTC). Image credit: NASA/JPL-Caltech

NASA scientists are tracking the upcoming Halloween flyby of asteroid 2015 TB145 with several optical observatories and the radar capabilities of the agency’s Deep Space Network at Goldstone, California. The asteroid will fly past Earth at a safe distance slightly farther than the moon’s orbit on Oct. 31 at 10:01 a.m. PDT (1:01 p.m. EDT). Scientists are treating the flyby of the estimated 1,300-foot-wide (400-meter) asteroid as a science target of opportunity, allowing instruments on “spacecraft Earth” to scan it during the close pass.

Published on Oct 29, 2015JPL scientist Marina Brozovic explains how radar will be used to study asteroid 2015 TB145 when it safely passes Earth on Oct. 31, 2015. Scientists are tracking the Halloween flyby with several optical observatories and the radar capabilities of the agency’s Deep Space Network at Goldstone, California. Radar images should be available within a few days of the flyby. The asteroid will fly past Earth at a safe distance slightly farther than the moon’s orbit on Oct. 31 at 10:01 a.m. PDT (1:01 p.m. EDT). Scientists are treating the flyby of the estimated 1,300-foot-wide (400-meter) asteroid as a science target of opportunity. 

Asteroid 2015 TB145 was discovered on Oct. 10, 2015, by the University of Hawaii’s Pan-STARRS-1 (Panoramic Survey Telescope and Rapid Response System) on Haleakala, Maui, part of the NASA-funded Near-Earth Object Observation (NEOO) Program. According to the catalog of near-Earth objects (NEOs) kept by the Minor Planet Center, this is the closest currently known approach by an object this large until asteroid 1999 AN10, at about 2,600 feet (800 meters) in size, approaches at about 1 lunar distance (238,000 miles from Earth) in August 2027.

“The trajectory of 2015 TB145 is well understood,” said Paul Chodas, manager of the Center for Near Earth Object Studies at NASA’s Jet Propulsion Laboratory, Pasadena, California. “At the point of closest approach, it will be no closer than about 300,000 miles — 480,000 kilometers or 1.3 lunar distances. Even though that is relatively close by celestial standards, it is expected to be fairly faint, so night-sky Earth observers would need at least a small telescope to view it.

The gravitational influence of the asteroid is so small it will have no detectable effect on the moon or anything here on Earth, including our planet’s tides or tectonic plates

The Center for NEO Studies at JPL is a central node for NEO data analysis in NASA’s Near-Earth Object Observation Program and a key group involved with the international collaboration of astronomers and scientists who keep watch on the sky with their telescopes, looking for asteroids that could be a hazard to impact our planet and predicting their paths through space for the foreseeable future

“The close approach of 2015 TB145 at about 1.3 times the distance of the moon’s orbit, coupled with its size, suggests it will be one of the best asteroids for radar imaging we’ll see for several years,” said Lance Benner, of JPL, who leads NASA’s asteroid radar research program. “We plan to test a new capability to obtain radar images with two-meter resolution for the first time and hope to see unprecedented levels of detail.”

During tracking, scientists will use the 34-meter (110-foot) DSS 13 antenna at Goldstone to bounce radio waves off the asteroid. Radar echoes will in turn be collected by the National Radio Astronomy Observatory’s Green Bank Telescope in Green Bank, West Virginia, and the National Astronomy and Ionosphere Center’s Arecibo Observatory, Puerto Rico. NASA scientists hope to obtain radar images of the asteroid as fine as about 7 feet (2 meters) per pixel. This should reveal a wealth of detail about the object’s surface features, shape, dimensions and other physical properties

“The asteroid’s orbit is very oblong with a high inclination to below the plane of the solar system,” said Benner. “Such a unique orbit, along with its high encounter velocity — about 35 kilometers or 22 miles per second — raises the question of whether it may be some type of comet. If so, then this would be the first time that the Goldstone radar has imaged a comet from such a close distance.”

NASA’s Near-Earth Object Observations Program detects, tracks and characterizes asteroids and comets passing within 30 million miles of Earth using both ground- and space-based telescopes. The NEOO Program, sometimes called “Spaceguard,” discovers these objects, characterizes the physical nature of a subset of them, and predicts their paths to determine if any could be potentially hazardous to our planet. There are no known credible impact threats to date — only the ongoing and harmless in-fall of meteoroids, tiny asteroids that burn up in the atmosphere

JPL hosts the Center for Near-Earth Object Studies for NASA’s Near-Earth Object Observations Program within the agency’s Science Mission Directorate. JPL is a division of the California Institute of Technology in Pasadena.

More information about asteroids and near-Earth objects is at:  http://neo.jpl.nasa.gov and http://www.jpl.nasa.gov/asteroidwatch

Excitement Grows as NASA Carbon Sleuth Begins Year Two

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Global average carbon dioxide concentrations as seen by NASA's Orbiting Carbon Observatory-2 mission, June 1-15, 2015. OCO-2 measures carbon dioxide from the top of Earth's atmosphere to its surface. Higher carbon dioxide concentrations are in red, with lower concentrations in yellows and greens. Credit: NASA/JPL-Caltech
Global average carbon dioxide concentrations as seen by NASA’s Orbiting Carbon Observatory-2 mission, June 1-15, 2015. OCO-2 measures carbon dioxide from the top of Earth’s atmosphere to its surface. Higher carbon dioxide concentrations are in red, with lower concentrations in yellows and greens. Credit: NASA/JPL-Caltech

Scientists busy poring over more than a year of data from NASA’s Orbiting Carbon Observatory-2 (OCO-2) mission are seeing patterns emerge as they seek answers to the science questions that drive the mission.

Launched in July 2014, OCO-2, an experimental carbon-dioxide measurement mission, is designed to give the international science community a new view of the global carbon cycle in unprecedented detail. During its two-year primary mission, the satellite observatory is tracking the large-scale movement of carbon between Earth’s atmosphere, its plants and soil, and the ocean, from season to season and from year to year. OCO-2 began routine science operations in September 2014.

“We can already clearly see patterns of seasonal change and variations in carbon dioxide around the globe,” said Annmarie Eldering, OCO-2 deputy project scientist at NASA’s Jet Propulsion Laboratory in Pasadena, California. “Far more subtle features are expected to emerge over time.”

A new animation depicting the first full year of OCO-2 science operations is available at:

Armed with a full annual cycle of data, OCO-2 scientists are now beginning to study the net sources of carbon dioxide as well as their “sinks” — places in the Earth system that store carbon, such as the ocean and plants on land. This information will help scientists better understand the natural processes currently absorbing more than half the carbon dioxide emitted into the atmosphere by human activities. This is a key to understanding how Earth’s climate may change in the future as greenhouse gas concentrations increase.

The first year of data from the mission reveals a portrait of a dynamic, living planet. Between mid-May and mid-July 2015, OCO-2 saw a dramatic reduction in the abundance of atmospheric carbon dioxide across the northern hemisphere, as plants on land sprang to life and began rapidly absorbing carbon dioxide from the air to form new leaves, stems and roots.

During this intense, two-month period, known as the “spring drawdown,” OCO-2 measurements show the concentration of atmospheric carbon dioxide over much of the northern hemisphere decreased by two to three percent. That’s 8 to 12 parts per million out of the global average background concentration of 400 parts per million.

“That’s a big but expected change,” said Eldering.

“This is the first time we’ve ever had the opportunity to observe the spring drawdown across the entire northern hemisphere with this kind of spatial resolution, seeing changes from week to week.”

Also as expected, OCO-2 data show increased concentrations of carbon dioxide associated with human activities. Higher carbon dioxide levels of several parts per million are seen in regions where fossil fuels are being consumed by large power plants or megacities. Enhanced levels are also seen in the Amazon, Central Africa and Indonesia, where forests are being cleared and burned to create fields for agricultural use.

Researchers Abhishek Chatterjee of the Global Modeling and Assimilation Office at NASA’s Goddard Space Flight Center, Greenbelt, Maryland; and Michelle Gierach and Dave Schimel of JPL are investigating a strong correlation observed between atmospheric carbon dioxide over the Pacific Ocean and the current El Nino.

Fluctuations in carbon dioxide appear to be strongly linked with warmer sea surface temperatures. OCO-2’s unprecedented density of measurements is giving researchers a unique data set to understand and separate the roles that sea surface temperatures, winds, regional emissions and other variables may be playing in the carbon dioxide concentrations.

“We believe 2016 will see breakthrough OCO-2 research results, as scientists work to unravel the mysteries of finding carbon dioxide sources and natural sinks,” said Eldering.

Through most of OCO-2’s first year in space, the mission team was busy calibrating its science instrument, learning how to process its massive amount of data, and delivering data products to NASA’s Goddard Earth Sciences Data and Information Services Center (GES-DISC) in Greenbelt, Maryland, for distribution to the world’s science community.

Scientists are comparing OCO-2 data to ground-based measurements to validate the satellite data and tie it to internationally accepted standards for accuracy and precision.

Routine delivery of OCO-2 data — calibrated spectra of reflected sunlight that reveal the fingerprints of carbon dioxide — began in late 2014, while estimates of carbon dioxide derived from cloud-free OCO-2 observations have been delivered since March 2015. Recently, the OCO-2 team reprocessed the OCO-2 data set to incorporate improvements in instrument calibration and correct other known issues with the original data release.

Every day, OCO-2 orbits Earth 14.5 times and collects and returns about a million measurements. After eliminating data contaminated by clouds, aerosols and steep terrain, between 10 to 13 percent of the measurements are of sufficient quality to derive accurate estimates of the average carbon dioxide concentration between Earth’s surface and space. That’s at least 100 times more carbon dioxide measurements than from all other sources of precise carbon dioxide data combined.

NASA uses the vantage point of space to increase our understanding of our home planet, improve lives and safeguard our future. NASA develops new ways to observe and study Earth’s interconnected natural systems with long-term data records. The agency freely shares this unique knowledge and works with institutions around the world to gain new insights into how our planet is changing.

For more information on OCO-2, visit: http://www.nasa.gov/oco-2

For more information about NASA’s Earth science activities, visit: http://www.nasa.gov/earth

Cassini Begins Series of Flybys with Close-up of Saturn Moon Enceladus

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LATEST NEWS
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Cassini Begins Series of Flybys with Close-up of Saturn Moon Enceladus

NASA’s Cassini spacecraft will wrap up its time in the region of Saturn’s large, icy moons with a series of three close encounters with Enceladus starting Wednesday, Oct. 14. Images are expected to begin arriving one to two days after the flyby, which will provide the first opportunity for a close-up look at the north polar region of Enceladus.

Wednesday’s flyby is considered a moderately close approach for Cassini, which will pass at an altitude of 1,142 miles (1,839 kilometers) above the moon’s surface. Closest approach to Enceladus will occur at 3:41 a.m. PDT (6:41 a.m. EDT). The spacecraft’s final two approaches will take place in late October and mid-December.

During Cassini’s early-mission encounters with the moon, the northern terrain of Enceladus was masked by wintry darkness. Now that the summer sun is shining on the high northern latitudes, scientists will be looking for signs of ancient geological activity similar to the geyser-spouting, tiger-stripe fractures in the moon’s south polar region. Features observed during the flyby could help them understand whether the north also was geologically active at some time in the past.

“We’ve been following a trail of clues on Enceladus for 10 years now,” said Bonnie Buratti, a Cassini science team member and icy moons expert at NASA’s Jet Propulsion Laboratory in Pasadena, California. “The amount of activity on and beneath this moon’s surface has been a huge surprise to us. We’re still trying to figure out what its history has been, and how it came to be this way.”

Since Cassini’s 2005 discovery of continually-erupting fountains of icy material on Enceladus, the Saturn moon has become one of the most promising places in the solar system to search for present-day habitable environments. Mission scientists announced evidence in March that hydrothermal activity may be occurring on the seafloor of the moon’s underground ocean. In September they broke news that its ocean — previously thought to be only a regional sea — was, in fact, global.

“The global nature of Enceladus’ ocean and the inference that hydrothermal systems might exist at the ocean’s base strengthen the case that this small moon of Saturn may have environments similar to those at the bottom of our own ocean,” said Jonathan Lunine, an interdisciplinary scientist on the Cassini mission at Cornell University in Ithaca, New York. “It is therefore very tempting to imagine that life could exist in such a habitable realm, a billion miles from our home.”

The Oct. 14 encounter will serve as a prelude to the main event, a flyby of Enceladus on Wednesday, Oct. 28, during which Cassini will come dizzyingly close to the icy moon, passing a mere 30 miles (49 kilometers) above the moon’s south polar region. During this encounter, Cassini will make its deepest-ever dive through the moon’s plume of icy spray, collecting images and valuable data about what’s going on beneath the frozen surface. Cassini scientists are hopeful data from that flyby will provide evidence of how much hydrothermal activity is occurring in the moon’s ocean, and how the amount of activity impacts the habitability of Enceladus’ ocean.

Cassini’s final close flyby on Dec. 19 will examine how much heat is coming from the moon’s interior from an altitude of 3,106 miles (4,999 kilometers).

An online toolkit for all three final Enceladus flybys is available at:

http://solarsystem.nasa.gov/finalflybys

Cassini arrived at Saturn in 2004 and still has about two years left on its mission. Beginning in November, mission controllers will begin to slowly raise Cassini’s orbit out of the space around the Saturn’s equator, where flybys of the large moons are more common. Coming up are a number of closest-ever brushes with the small moons that huddle near the planet’s rings.

“We’ll continue observing Enceladus and its remarkable activity for the remainder of our precious time at Saturn,” said Linda Spilker, Cassini project scientist at JPL. “But these three encounters will be our last chance to see this fascinating world up close for many years to come.”

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

For more information about Cassini, visit:

http://www.nasa.gov/cassini

http://saturn.jpl.nasa.gov

NASA Jet Propulsion Laboratory | jplnewsroom | NASA’s Jet Propulsion Laboratory | 4800 Oak Grove Dr | Pasadena, CA 91109

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NASA/Forest Service Maps Aid Fire Recovery

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The 2013 Rim fire in and near Yosemite National Park, California, was the third largest in the state’s history, burning more than 250,000 acres. Almost two years later, forest restoration efforts are still ongoing. Image credit: USFS/Mike McMillan

 Fast Facts:

  • New maps of burn areas from two California megafires are so detailed, they can show individual trees.
  • The maps are being used in rehabilitating the burn areas and protecting wildlife.

New maps of two recent California megafires that combine unique data sets from the U.S. Forest Service and NASA’s Jet Propulsion Laboratory in Pasadena, California, are answering some of the urgent questions that follow a huge wildfire: In all the acres of blackened landscape, where are the live trees to provide seed and regrow the forest? Which dead trees could endanger workers rebuilding roads and trails? What habitats have been created for fire-dependent wildlife species? 

The maps, so detailed that they show individual trees, cover the areas of two California megafires — the 2013 Rim fire, which burned more than 250,000 acres (1,000 square kilometers) near and in Yosemite National Park, and 2014’s very intense King fire near Lake Tahoe — before, during and after the active burns. As the Forest Service directs ongoing recovery and restoration projects in the two areas, it is using the maps to target its efforts toward important goals such as reducing soil erosion and protecting wildlife.

  

The maps include observations from three instruments: JPL’s Airborne Visible/Infrared Imaging Spectrometer (AVIRIS), which collects images in visible light; JPL’s MODIS/ASTER Airborne Simulator (MASTER), which observes in thermal infrared — in other words, it “sees” heat; and lidar data showing terrain and canopy with such high resolution that individual trees are outlined.

Carlos Ramirez, program manager of the USFS’s Remote Sensing Laboratory, McClellan, California, described three ways the Forest Service is currently using the maps:

— “In some areas of the King fire, you don’t see any green for miles and miles,” said Ramirez. “It’s likely there are not going to be any viable seed sources where the fire was that intense. With the AVIRIS data set, we get an inventory of living vegetation and the condition of it. That gives people in charge of putting together restoration plans an idea of where to focus their attention.”

— Wildfires increase erosion by burning off plants that stabilize soil and diffuse rain. Intense burns often create a water-resistant layer atop the soil so that rain runs off instead of soaking in, cutting deep channels and increasing flood and landslide danger downstream. The maps identify where trees and plants are still alive and erosion control is not needed. 

— Ramirez is working with the University of California, Davis, and nongovernmental organizations to manage the goals of simultaneously clearing hazardous burned timber and preserving habitats for as many species as possible. “Some of these high-severity burn patches are highly desirable habitats,” he said. The maps allow the team to better assess habitat quality for species such as the black-backed woodpecker, which thrives on beetles that live in dead trees.

 

These before-and-after lidar images from the King fire show an area on the west side of the Rubicon River where fire damage was severe. Blue is ground level; lighter colors are higher. A road, bordered by dense trees in the before image, and part of a bridge (green) are at center. Image credit: USFS
 

The NASA observations were acquired in the development of a satellite mission called the Hyperspectral Infrared Imager (HyspIRI), which will study Earth’s ecosystems and provide critical information on natural disasters. HyspIRI is many years from launch and not yet under construction, but AVIRIS and MASTER are airborne prototypes of its two instruments, developed so that scientists can work out scientific and technological issues in advance. Natasha Stavros of JPL recognized the potential value of the Rim fire observations and began collaborating with Ramirez to assemble the maps. When the King fire broke out, the scientists received additional NASA funding to document that fire and its aftermath as well. They hope to create another set of maps if another California megafire breaks out in 2015.

Scientist Janice Coen of the National Center for Atmospheric Research, Boulder, Colorado, is using the MASTER maps of the King fire in independent research with the Coupled Atmosphere – Wildland Fire Environment model, which simulates the interactions of weather and fires. She hopes to gain insight into why the fire grew so quickly. Fires that intense usually are fanned by high winds, but weather stations around the King fire recorded very little wind when it started. “If you’re using the standard tools, you can’t explain the rapid fire growth,” she said. “The evolution of this fire seems to depend very much on winds the fire itself generated as it burned, and those winds in turn depend on the characteristics of the vegetation the fire had for fuel. It’s a good case study, because the new data sets can distinguish between vegetation characteristics that other data sets don’t distinguish.”

A database of detailed maps is online at: http://wildfire.jpl.nasa.gov/data 

NASA’s NuSTAR Captures Possible ‘Screams’ from Zombie Stars

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NASA’s Nuclear Spectroscopic Telescope Array, or NuSTAR, has captured a new high-energy X-ray view (magenta) of the bustling center of our Milky Way galaxy. Image credit: NASA/JPL-Caltech

Peering into the heart of the Milky Way galaxy, NASA’s Nuclear Spectroscopic Telescope Array (NuSTAR) has spotted a mysterious glow of high-energy X-rays that, according to scientists, could be the “howls” of dead stars as they feed on stellar companions. 

“We can see a completely new component of the center of our galaxy with NuSTAR’s images,” said Kerstin Perez of Columbia University in New York, lead author of a new report on the findings in the journal Nature. “We can’t definitively explain the X-ray signal yet — it’s a mystery. More work needs to be done.”

The center of our Milky Way galaxy is bustling with young and old stars, smaller black holes and other varieties of stellar corpses — all swarming around a supermassive black hole called Sagittarius A*.

NuSTAR, launched into space in 2012, is the first telescope capable of capturing crisp images of this frenzied region in high-energy X-rays. The new images show a region around the supermassive black hole about 40 light-years across. Astronomers were surprised by the pictures, which reveal an unexpected haze of high-energy X-rays dominating the usual stellar activity.

“Almost anything that can emit X-rays is in the galactic center,” said Perez. “The area is crowded with low-energy X-ray sources, but their emission is very faint when you examine it at the energies that NuSTAR observes, so the new signal stands out.”

Astronomers have four theories to explain the baffling X-ray glow, three of which involve different classes of stellar corpses. When stars die, they don’t always go quietly into the night. Unlike stars like our sun, collapsed dead stars that belong to stellar pairs, or binaries, can siphon matter from their companions. This zombie-like “feeding” process differs depending on the nature of the normal star, but the result may be an eruption of X-rays.

According to one theory, a type of stellar zombie called a pulsar could be at work. Pulsars are the collapsed remains of stars that exploded in supernova blasts. They can spin extremely fast and send out intense beams of radiation. As the pulsars spin, the beams sweep across the sky, sometimes intercepting Earth, like lighthouse beacons.

“We may be witnessing the beacons of a hitherto hidden population of pulsars in the galactic center,” said co-author Fiona Harrison of the California Institute of Technology in Pasadena, principal investigator of NuSTAR. “This would mean there is something special about the environment in the very center of our galaxy.”

Other possible culprits include heavy-set stellar corpses called white dwarfs, which are the collapsed, burned-out remains of stars not massive enough to explode in supernovae. Our sun is such a star, and is destined to become a white dwarf in about five billion years. Because these white dwarfs are much denser than they were in their youth, they have stronger gravity and can produce higher-energy X-rays than normal. Another theory points to small black holes that slowly feed off their companion stars, radiating X-rays as material plummets down into their bottomless pits.

Alternatively, the source of the high-energy X-rays might not be stellar corpses at all, astronomers say, but rather a diffuse haze of charged particles called cosmic rays. The cosmic rays might originate from the supermassive black hole at the center of the galaxy as it devours material. When the cosmic rays interact with surrounding, dense gas, they emit X-rays.

However, none of these theories match what is known from previous research, leaving the astronomers largely stumped.

“This new result just reminds us that the galactic center is a bizarre place,” said co-author Chuck Hailey of Columbia University. “In the same way people behave differently walking on the street instead of jammed on a crowded rush-hour subway, stellar objects exhibit weird behavior when crammed in close quarters near the supermassive black hole.” 

The team says more observations are planned. Until then, theorists will be busy exploring the above scenarios or coming up with new models to explain what could be giving off the puzzling high-energy X-ray glow.

“Every time that we build small telescopes like NuSTAR, which improve our view of the cosmos in a particular wavelength band, we can expect surprises like this,” said Paul Hertz, the astrophysics division director at NASA Headquarters in Washington.

NuSTAR is a Small Explorer mission led by Caltech and managed by NASA’s Jet Propulsion Laboratory in Pasadena, California, for NASA’s Science Mission Directorate in Washington.

More information is online at: http://www.nasa.gov/nustar