NASA Awards Contract for Continued Operations of its Jet Propulsion Laboratory

NASA has awarded a contract to the California Institute of Technology (Caltech) in Pasadena, California, to continue operations of the agency's Jet Propulsion Laboratory (JPL), also in Pasadena.

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Young Kansans to Call Space Station from Eisenhower Presidential Library

Kansas Boy Scout troops and students will participate in a live downlink event with astronauts aboard the International Space Station next week as part of NASA’s Year of Education on Station.

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New NASA Research, Hardware Heading to Space Station on 15th SpaceX Resupply Mission

Experiments investigating cellular biology, Earth science and artificial intelligence are among the research heading to the International Space Station following Friday’s launch of a NASA-contracted SpaceX Dragon spacecraft at 5:42 a.m. EDT.

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Four Other Things ECOSTRESS Can See

ECOSTRESS will track heat stress in plants, but heat is a warning sign in other areas, too. Here are four other fields where the super-precise temperature data could help.

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NASA to Hold Teleconference for Media, Industry on Unmanned Aircraft Flight in Public Airspace

NASA will host a teleconference for members of the media and aviation industry at 4 p.m. EDT on Thursday, June 28, to discuss the details and preliminary results of the agency’s first large-scale, remotely piloted aircraft flight in the national airspace using detect and avoid technology to fly without a safety chase aircraft.

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NASA Technologies Significantly Reduce Aircraft Noise

A series of NASA flight tests has successfully demonstrated technologies that achieve a significant reduction in the noise generated by aircraft and heard by communities near airports.

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Media Invited to Preview Expedition to Ocean Twilight Zone

Media are invited to Seattle on Friday, Aug. 9, to preview a seaborne expedition to study microscopic organisms in the dark depths of the sea that play a critical role in removing carbon dioxide from Earth’s atmosphere.

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NASA Television to Air Launch of Next Space Station Resupply Mission

NASA commercial cargo provider SpaceX is targeting no earlier than 5:42 a.m. EDT Friday, June 29, for the launch of its 15th resupply mission to the International Space Station. Live coverage will begin on NASA Television and the agency’s website Thursday, June 28, with prelaunch events.

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New NASA Mission to Detect Plant Water Use from Space

Doctors learn a lot about their patients' health by taking their temperature. An elevated temperature, or fever, can be a sign of illness. The same goes for plants, but their temperatures on a global scale are harder to measure than the temperatures of individual people.

That's about to change, thanks to a new NASA instrument that soon will be installed on the International Space Station called ECOSTRESS, or ECOsystem Spaceborne Thermal Radiometer Experiment on Space Station. ECOSTRESS will measure the temperature of plants from space. This will enable researchers to determine plant water use and to study how drought conditions affect plant health.

Plants draw in water from the soil, and as they are heated by the Sun, the water is released through pores on the plants' leaves through a process called transpiration. This cools the plant down, much as sweating does in humans. However, if there is not enough water available to the plants, they close their pores to conserve water, causing their temperatures to rise.

Plants use those same pores to take up carbon dioxide from the atmosphere for photosynthesis - the process they use to turn carbon dioxide and water into the sugar they use as food. If they continue to experience insufficient water availability, or "water stress," they eventually starve or overheat, and die.

ECOSTRESS data will show these changes in plants' temperatures, providing insight into their health and water use while there is still time for water managers to correct agricultural water imbalances.

"When a plant is so stressed that it turns brown, it's often too late for it to recover," said Simon Hook, ECOSTRESS principal investigator at NASA's Jet Propulsion Laboratory in Pasadena, California. "But measuring the temperature of the plant lets you see that a plant is stressed before it reaches that point."

These temperature measurements are also considered an early indicator of potential droughts. When plants in a given area start showing signs of water stress through elevated temperature, an agricultural drought is likely underway. Having these data in advance gives the agricultural community a chance to prepare and/or respond accordingly.

"ECOSTRESS will allow us to monitor rapid changes in crop stress at the field level, enabling earlier and more accurate estimates of how yields will be impacted," said Martha Anderson, an ECOSTRESS science team member with the U.S. Department of Agriculture in Beltsville, Maryland. "Even short-term moisture stress, if it occurs during a critical stage of crop growth, can significantly impact productivity."

ECOSTRESS will hitch a ride to the space station on a NASA-contracted, SpaceX cargo resupply mission scheduled to launch from Cape Canaveral Air Force Station in Florida on June 29. Once it arrives, it will be robotically installed on the exterior of the station's Japanese Experiment Module Exposed Facility Unit.

Over the next year, ECOSTRESS will use the space station's unique low Earth orbit to collect data over multiple areas of land at different times of day. The instrument will produce detailed images of areas as small as 43 by 76 yards (40 by 70 meters) -- about the size of a small farm -- every three to five days.

Other instruments in space can make measurements with the same level of detail or at different times of day -- but not both. ECOSTRESS' dual capability makes it especially important for scientists trying to better understand our natural ecosystems and others working toward improved food security and water resource management.

"As water resources become more critical for our growing population, we need to track precisely how much water our crops need," said ECOSTRESS science lead Josh Fisher of JPL. "We need to know when plants are becoming susceptible to droughts, and we need to know which parts of the ecosystem are more vulnerable because of water stress."

Although not part of its primary mission, ECOSTRESS temperature data will also be valuable for other studies that require temperature information, such as detecting and characterizing volcanoes, wildfires and heat waves.

JPL built and manages the ECOSTRESS mission for NASA's Earth Science Division in the Science Mission Directorate at NASA Headquarters in Washington. ECOSTRESS is sponsored by NASA's Earth System Science Pathfinder program, managed by NASA's Langley Research Center in Hampton, Virginia.

For more information on ECOSTRESS, visit:

https://www.nasa.gov/ecostress

News Media Contact

Alan Buis

Jet Propulsion Laboratory, Pasadena, Calif.

818-354-0474

Alan.buis@jpl.nasa.gov

Written by Esprit Smith

JPL Media Relations

2018-139

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Astronomers See Distant Eruption as Black Hole Destroys Star

For the first time, astronomers have directly imaged the formation and expansion of a fast-moving jet of material ejected when the powerful gravity of a supermassive black hole ripped apart a star that wandered too close to the massive monster.

The scientists tracked the event with radio and infrared telescopes, including the National Science Foundation's Very Long Baseline Array (VLBA) and NASA's Spitzer Space Telescope, in a pair of colliding galaxies called Arp 299. The galaxies are nearly 150 million light-years from Earth. At the core of one of the galaxies, a black hole 20 million times more massive than the Sun shredded a star more than twice the Sun's mass, setting off a chain of events that revealed important details of the violent encounter. The researchers also used observations of Arp 299 made by NASA's Hubble space telescope prior to and after the appearance of the eruption.

Only a small number of such stellar deaths, called tidal disruption events, or TDEs, have been detected. Theorists have suggested that material pulled from the doomed star forms a rotating disk around the black hole, emitting intense X-rays and visible light, and also launches jets of material outward from the poles of the disk at nearly the speed of light.

"Never before have we been able to directly observe the formation and evolution of a jet from one of these events," said Miguel Perez-Torres, of the Astrophysical Institute of Andalucia in Granada, Spain, and an author on a paper describing the finding.

Discovery of a jet

The first indication came on January 30, 2005, when astronomers using the William Herschel Telescope in the Canary Islands discovered a bright burst of infrared emission coming from the nucleus of one of the colliding galaxies in Arp 299. On July 17, 2005, the VLBA revealed a new, distinct source of radio emission from the same location.

"As time passed, the new object stayed bright at infrared and radio wavelengths, but not in visible light and X-rays," said Seppo Mattila, of the University of Turku in Finland, another author on the new paper. "The most likely explanation is that thick interstellar gas and dust near the galaxy's center absorbed the X-rays and visible light, then re-radiated it as infrared." The researchers used the Nordic Optical Telescope on the Canary Islands and NASA's Spitzer to follow the object's infrared emission.

Continued observations with the VLBA, the European VLBI Network (EVN), and other radio telescopes, carried out over nearly a decade, showed the source of radio emission expanding in one direction, just as expected for a jet. The measured expansion indicated that the material in the jet moved at an average of one-fourth the speed of light. The radio waves are not absorbed by the dust, but pass through it.

These observations used multiple radio-telescope antennas, separated by thousands of miles, to gain the resolving power, or ability to see fine detail, required to detect the expansion of an object so distant.

Monster appetite

Most galaxies have supermassive black holes, containing millions to billions of times the mass of the Sun, at their cores. In a black hole, the mass is so concentrated that its gravitational pull is so strong that not even light can escape. When those supermassive black holes are actively drawing in material from their surroundings, that material forms a rotating disk around the black hole, and super-fast jets of particles are launched outward. This is the phenomenon seen in radio galaxies and quasars.

"Much of the time, however, supermassive black holes are not actively devouring anything, so they are in a quiet state," Perez-Torres explained. "Tidal disruption events can provide us with a unique opportunity to advance our understanding of the formation and evolution of jets in the vicinities of these powerful objects."

"Because of the dust that absorbed any visible light, this particular tidal disruption event may be just the tip of the iceberg of what until now has been a hidden population," Mattila said. "By looking for these events with infrared and radio telescopes, we may be able to discover many more, and learn from them."

Such events may have been more common in the distant universe, so studying them may help scientists understand the environment in which galaxies developed billions of years ago.

The discovery, the scientists said, came as a surprise. The initial infrared burst was discovered as part of a project that sought to detect supernova explosions in such colliding pairs of galaxies. Arp 299 has seen numerous stellar explosions, and has been dubbed a "supernova factory." This new object originally was considered to be a supernova explosion. Only in 2011, six years after discovery, the radio-emitting portion began to show an elongation. Subsequent monitoring showed the expansion growing, confirming that what the scientists are seeing is a jet, not a supernova.

Mattila and Perez-Torres led a team of 36 scientists from 26 institutions around the world in the observations of Arp 299. They published their findings in the June 14 issue of the journal Science.

The Long Baseline Observatory is a facility of the National Science Foundation, operated under cooperative agreement by Associated Universities, Inc. NASA's Jet Propulsion Laboratory, Pasadena, California, manages the Spitzer Space Telescope mission for NASA's Science Mission Directorate, Washington. Science operations are conducted at the Spitzer Science Center at Caltech in Pasadena. Spacecraft operations are based at Lockheed Martin Space Systems Company, Littleton, Colorado. Data are archived at the Infrared Science Archive housed at IPAC at Caltech. Caltech manages JPL for NASA.

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

For more information about NASA's Hubble Space Telescope, visit:

https://www.nasa.gov/hubble

For more information about NASA's Spitzer Space Telescope, visit:

https://www.nasa.gov/spitzer

News Media Contact

Calla Cofield

Jet Propulsion Laboratory, Pasadena, Calif.

818-393-1821

calla.e.cofield@jpl.nasa.gov

Dave Finley

Public Information Officer, NRAO

575-835-7302

dfinley@nrao.edu

2018-138

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NASA Encounters the Perfect Storm for Science

NASA Administrator Statement on Space Policy Directive-3

The following is a statement from NASA Administrator Jim Bridenstine on Monday’s signing of Space Policy Directive-3 by President Donald Trump:

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NASA, NSF Plunge Into Ocean ‘Twilight Zone’ to Explore Ecosystem Carbon Flow

A large multidisciplinary team of scientists, equipped with advanced underwater robotics and an array of analytical instrumentation, will set sail for the northeastern Pacific Ocean this August.

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Brooklyn Students to Link Up with NASA Astronauts on Space Station

Students from Brooklyn, New York, will have the opportunity to talk with astronauts on the International Space Station this week as part of NASA’s Year of Education on Station.

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Record-Setting NASA Astronaut Peggy Whitson Retires

NASA astronaut Peggy Whitson, who holds the U.S. record for most cumulative time in space, is retiring from the agency, effective Friday.

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Ramp-Up in Antarctic Ice Loss Speeds Sea Level Rise

Ice losses from Antarctica have tripled since 2012, increasing global sea levels by 0.12 inch (3 millimeters) in that timeframe alone, according to a major new international climate assessment funded by NASA and ESA (European Space Agency).

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First Astronaut of 2013 Class to Fly to Space Available for Media Interviews

NASA astronaut Nick Hague, along with his crewmate Alexey Ovchinin of the Russian space agency Roscosmos, will discuss their upcoming mission to the International Space Station in a news conference at 2 p.m. EDT Monday, June 18, at NASA’s Johnson Space Center in Houston.

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NASA Finds Ancient Organic Material, Mysterious Methane on Mars

NASA’s Curiosity rover has found new evidence preserved in rocks on Mars that suggests the planet could have supported ancient life, as well as new evidence in the Martian atmosphere that relates to the search for current life on the Red Planet.

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NASA TV to Air US Spacewalk at International Space Station

NASA astronauts will embark on a six-and-a-half-hour spacewalk Thursday, June 14, during which they will install new high-definition cameras to capture spacecraft docking with the International Space Station, including new American-made spacecraft with scheduled test flights later this year.

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Juno Solves 39-Year Old Mystery of Jupiter Lightning

Ever since NASA's Voyager 1 spacecraft flew past Jupiter in March, 1979, scientists have wondered about the origin of Jupiter's lightning. That encounter confirmed the existence of Jovian lightning, which had been theorized for centuries. But when the venerable explorer hurtled by, the data showed that the lightning-associated radio signals didn't match the details of the radio signals produced by lightning here at Earth.

In a new paper published in Nature today, scientists from NASA's Juno mission describe the ways in which lightning on Jupiter is actually analogous to Earth's lightning. Although, in some ways, the two types of lightning are polar opposites.

"No matter what planet you're on, lightning bolts act like radio transmitters -- sending out radio waves when they flash across a sky," said Shannon Brown of NASA's Jet Propulsion Laboratory in Pasadena, California, a Juno scientist and lead author of the paper. "But until Juno, all the lightning signals recorded by spacecraft [Voyagers 1 and 2, Galileo, Cassini] were limited to either visual detections or from the kilohertz range of the radio spectrum, despite a search for signals in the megahertz range. Many theories were offered up to explain it, but no one theory could ever get traction as the answer."

Enter Juno, which has been orbiting Jupiter since July 4, 2016. Among its suite of highly sensitive instruments is the Microwave Radiometer Instrument (MWR), which records emissions from the gas giant across a wide spectrum of frequencies.

"In the data from our first eight flybys, Juno's MWR detected 377 lightning discharges," said Brown. "They were recorded in the megahertz as well as gigahertz range, which is what you can find with terrestrial lightning emissions. We think the reason we are the only ones who can see it is because Juno is flying closer to the lighting than ever before, and we are searching at a radio frequency that passes easily through Jupiter's ionosphere."

While the revelation showed how Jupiter lightning is similar to Earth's, the new paper also notes that where these lightning bolts flash on each planet is actually quite different.

"Jupiter lightning distribution is inside out relative to Earth," said Brown. "There is a lot of activity near Jupiter's poles but none near the equator. You can ask anybody who lives in the tropics -- this doesn't hold true for our planet."

Why do lightning bolts congregate near the equator on Earth and near the poles on Jupiter? Follow the heat.

Earth's derives the vast majority of its heat externally from solar radiation, courtesy of our Sun. Because our equator bears the brunt of this sunshine, warm moist air rises (through convection) more freely there, which fuels towering thunderstorms that produce lightning.

Jupiter's orbit is five times farther from the Sun than Earth's orbit, which means that the giant planet receives 25 times less sunlight than Earth. But even though Jupiter's atmosphere derives the majority of its heat from within the planet itself, this doesn't render the Sun's rays irrelevant. They do provide some warmth, heating up Jupiter's equator more than the poles -- just as they heat up Earth. Scientists believe that this heating at Jupiter's equator is just enough to create stability in the upper atmosphere, inhibiting the rise of warm air from within. The poles, which do not have this upper-level warmth and therefore no atmospheric stability, allow warm gases from Jupiter's interior to rise, driving convection and therefore creating the ingredients for lightning.

"These findings could help to improve our understanding of the composition, circulation and energy flows on Jupiter," said Brown. But another question looms, she said. "Even though we see lightning near both poles, why is it mostly recorded at Jupiter's north pole?"

In a second Juno lightning paper published today in Nature Astronomy, Ivana Kolmašová of the Czech Academy of Sciences, Prague, and colleagues, present the largest database of lightning-generated low-frequency radio emissions around Jupiter (whistlers) to date. The data set of more than 1,600 signals, collected by Juno's Waves instrument, is almost 10 times the number recorded by Voyager 1. Juno detected peak rates of four lightning strikes per second (similar to the rates observed in thunderstorms on Earth) which is six times higher than the peak values detected by Voyager 1.

"These discoveries could only happen with Juno," said Scott Bolton, principal investigator of Juno from the Southwest Research Institute, San Antonio. "Our unique orbit allows our spacecraft to fly closer to Jupiter than any other spacecraft in history, so the signal strength of what the planet is radiating out is a thousand times stronger. Also, our microwave and plasma wave instruments are state-of-the-art, allowing us to pick out even weak lightning signals from the cacophony of radio emissions from Jupiter. "

NASA's Juno spacecraft will make its 13th science flyby over Jupiter's mysterious cloud tops on July 16.

NASA's Jet Propulsion Laboratory, Pasadena, California, manages the Juno mission for the principal investigator, Scott Bolton, of the Southwest Research Institute in San Antonio. Juno is part of NASA's New Frontiers Program, which is managed at NASA's Marshall Space Flight Center in Huntsville, Alabama, for NASA's Science Mission Directorate. The Microwave Radiometer instrument (MWR) was built by JPL. The Juno Waves instrument was provided by the University of Iowa. Lockheed Martin Space, Denver, built the spacecraft.

More information on Juno can be found at:

https://www.nasa.gov/juno

https://www.missionjuno.swri.edu

More information about Jupiter can be found at:

https://www.nasa.gov/jupiter

The public can follow the mission on Facebook and Twitter at:

https://www.facebook.com/NASAJuno

https://www.twitter.com/NASAJuno

News Media Contact

DC Agle

Jet Propulsion Laboratory, Pasadena, Calif.

818-393-9011

agle@jpl.nasa.gov

JoAnna Wendel

NASA Headquarters, Washington

202-358-1003

joanna.r.wendel@nasa.gov

Richard Lewis

University of Iowa, Iowa City

319-384-0012

richard-c-lewis@uiowa.edu

Deb Schmid

Southwest Research Institute, San Antonio

210-522-2254

dschmid@swri.org

2018-128

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Warm Water Creeps into Otherwise-Calm Central Pacific

After a mild La Niña late last year, temperatures, convection and rainfall rates in the equatorial Pacific Ocean returned to normal by early April of this year. An April 9 image of sea level height from the U.S./European Jason-3 satellite mission showed most of the ocean at neutral heights. But by the beginning of May, high sea levels began to build up in the Central Pacific. In the tropics, high sea levels are usually caused by a layer of warm water at or below the surface.

This patch of high sea level is slowly traveling eastward through the tropical Pacific Ocean along the equator. Known as a downwelling Kelvin wave, this type of signal is often a precursor to an El Niño event.

The Kelvin wave formed after a few short periods when winds changed from the prevailing easterlies to westerly -- known as westerly wind bursts -- in the far western Pacific in early 2018. In addition, there has been a general weakening of the easterly winds along the equator since January. Both of these wind conditions combine to create the Kelvin wave, which moves east along the equator and results in the spreading of warm water layers that are normally confined to the western Pacific Ocean eastward into the central Pacific. The red pattern visible at the equator on May 9 is the result of this downwelling Kelvin wave.

During a large El Niño, like the 2015-16 event, a huge area where sea levels are more than a foot (30 centimeters) higher than normal is visible in Jason-3 images. The high sea level is caused by a thick layer of warm water in the upper several hundred feet of the ocean. Such large El Niño events affect weather and climate across the globe, particularly in the western United States. In California, El Niños usually mean above-average winter rainfall, while Oregon and Washington typically see drier-than-normal winters.

El Niños happen when a series of Kelvin waves like this one spread warm water from west to east along the equator, causing high sea levels in the Central Pacific and sometimes as far east as the coastlines of Central and South America. The warm water is currently confined to the subsurface, with no warming at the ocean surface -- a first indicator of an upcoming El Niño event. But forecasters at agencies like NOAA (the National Oceanic and Atmospheric Administration) and ECMWF (European Centre for Medium-Range Weather Forecasts) will be watching closely for more Kelvin waves like this one as summer approaches.

NASA's Jet Propulsion Laboratory in Pasadena, California, manages the Jason-3 mission for NASA. NOAA operates Jason-3 in partnership with NASA, the French space agency (CNES), and the European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT).

News Media Contact

Alan Buis

Jet Propulsion Laboratory, Pasadena, California

818-354-0474

Alan.Buis@jpl.nasa.gov

Written by Carol Rasmussen

NASA's Earth Science News Team

2018-127

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Astronauts Safely in Orbit Following Launch to International Space Station

Three crew members are on their way to the International Space Station after launching from the Baikonur Cosmodrome in Kazakhstan at 7:12 a.m. EDT Wednesday (5:12 p.m. Baikonur time).

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NASA to Host Live Discussion on New Mars Science Results

The media and public are invited to ask questions during a live discussion at 2 p.m. EDT Thursday, June 7, on new science results from NASA’s Mars Curiosity rover.

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NASA Astronaut, Crewmates Safely Return to Earth from Space Station

Three members of the International Space Station Expedition 55 crew, including NASA astronaut Scott Tingle, returned to Earth Sunday after 168 days of living and working in low-Earth orbit.

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NEOWISE Thermal Data Reveal Surface Properties of Over 100 Asteroids

Nearly all asteroids are so far away and so small that the astronomical community only knows them as moving points of light. The rare exceptions are asteroids that have been visited by spacecraft, a small number of large asteroids resolved by NASA's Hubble Space Telescope or large ground-based telescopes, or those that have come close enough for radar imaging.

When seen by optical telescopes, these individual sources of reflected sunlight can provide some very valuable but also very basic information -- for example, the asteroid's orbit, a ballpark estimate of its size, sometimes an approximation of its shape, and perhaps an idea of its physical makeup. But to learn more about these elusive and important celestial objects requires a different type of instrument. An infrared sensor can, in the right circumstances, not only provide data on an asteroid's orbit and data that can be used to more accurately measure its size, but also chemical makeup and sometimes even its surface characteristics.

NASA's Near-Earth Object Wide-field Infrared Survey Explorer, or NEOWISE, spacecraft, in orbit around Earth, uses asteroid-hunting thermal sensors that allow an infrared view of asteroids without the obscuring effects of Earth's atmosphere. In a paper published recently in the journal Icarus, researchers led by Josef Hanuš, a scientist at the Astronomical Institute of Charles University, Prague, have made an in-depth analysis of more than 100 asteroids that have come under the temperature-sensing gaze of NEOWISE. This analysis tripled the number of asteroids which have undergone detailed "thermophysical" modeling of asteroid properties that vary with temperature. The results provide a more accurate glimpse into the surface properties of main belt asteroids and also reinforce the capabilities of spaceborne infrared observatories to accurately assess the sizes of asteroids.

Value of this technique

Thermophysical modeling is a gold mine for asteroid researchers because it allows a more comprehensive analysis of the nature of asteroids. Not all asteroids are suitable for thermophysical modeling because the necessary raw data sets are not always available. But Hanuš's team found 122 asteroids that not only had NEOWISE data, but also detailed models of their rotation states (how fast an object rotates around its axis, and the orientation of the axis in space) and multi-faceted models of the asteroid's 3D shape.

"Using archived data from the NEOWISE mission and our previously derived shape models, we were able to create highly detailed thermophysical models of 122 main belt asteroids," said Hanuš, lead author of the paper. "We now have a better idea of the properties of the surface regolith and show that small asteroids, as well as fast rotating asteroids, have little, if any, dust covering their surfaces." (Regolith is the term for the broken rocks and dust on the surface.)

It could be difficult for fast-rotating asteroids to retain very fine regolith grains because their low gravity and high spin rates tend to fling small particles off their surfaces and into space. Also, it could be that fast-rotating asteroids do not experience large temperature changes because the sun's rays are more rapidly distributed across their surfaces. That would reduce or prevent the thermal cracking of an asteroid's surface material that could cause the generation of fine grains of regolith.

Hanuš's team also found that their detailed calculations for estimated sizes of the asteroids they studied were consistent with those of the same asteroids calculated by the NEOWISE team using simpler models.

"With the asteroids for which we were able to gather the most information from other sources, our calculations of their sizes were consistent with the radiometrically-derived values performed by the NEOWISE team," said Hanuš. "The uncertainties were within 10 percent between the two sets of results."

"This is an important example of how space-based infrared data can accurately characterize asteroids," said Alan Harris, a senior scientist at the German Aerospace Center (DLR) based in Berlin, Germany, who specializes in thermal modeling of asteroids but was not involved with the study. "NEOWISE is leading the way in demonstrating the value of space-based infrared observatories for asteroid and near-Earth object discovery and characterization, both vital to our understanding these important inhabitants of our solar system."

From WISE to NEOWISE

Originally called the Wide-field Infrared Survey Explorer (WISE), the spacecraft was launched in December 2009 to study galaxies, stars, and solar system bodies by imaging the entire sky in infrared light. It was placed in hibernation in 2011 after its primary astrophysics mission was completed. In September 2013, it was reactivated, renamed NEOWISE and assigned a new mission: to assist NASA's efforts to identify and characterize the population of near-Earth objects. NEOWISE also is characterizing more distant populations of asteroids and comets to provide information about their sizes and compositions.

NASA's Jet Propulsion Laboratory in Pasadena, California, manages and operates the NEOWISE mission for NASA's Planetary Defense Coordination Office within the Science Mission Directorate in Washington. The Space Dynamics Laboratory in Logan, Utah built the science instrument. Ball Aerospace & Technologies Corp. of Boulder, Colorado built the spacecraft. Science data processing takes place at IPAC at Caltech in Pasadena. Caltech manages JPL for NASA.

The thermophysical modeling paper accepted by Icarus is available at:

https://arxiv.org/pdf/1803.06116.pdf

For more information about NEOWISE, visit:

https://www.nasa.gov/neowise

and

http://neowise.ipac.caltech.edu/

More information about asteroids and near-Earth objects is at:

https://www.jpl.nasa.gov/asteroidwatch

News Media Contact

DC Agle

Jet Propulsion Laboratory, Pasadena, Calif.

818-393-9011

agle@jpl.nasa.gov

JoAnna Wendel

NASA Headquarters, Washington

202-358-1003

joanna.r.wendel@nasa.gov

2018-122

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NASA Selects US Companies to Advance Space Resource Collection

NASA has selected 10 companies to conduct studies and advance technologies to collect, process and use space-based resources for missions to the Moon and Mars.

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