Friday, July 18, 2014

NASA Releases Earth Day 'Global Selfie' Mosaic

NASA Releases Earth Day 'Global Selfie' Mosaic:

A low-resolution preview of the 3.2-billion-pixel sized NASA Earth Day Global Selfie 2014 photo mosaic.
A low-resolution preview of the 3.2-billion-pixel sized NASA Earth Day Global Selfie 2014 photo mosaic. The image is comprised of more than 36,000 individual photos submitted by people around the world.
Credit: NASA/JPL-Caltech/NOAA

› Larger image


May 22, 2014

A low-resolution preview of the 3.2-billion-pixel sized NASA Earth Day Global Selfie 2014 photo mosaic. The image is comprised of more than 36,000 individual photos submitted by people around the world. Image credit: NASA/JPL-Caltech/NOAA

For Earth Day this year, NASA invited people around the world to step outside to take a "selfie" and share it with the world on social media. NASA released Thursday a new view of our home planet created entirely from those photos.

The "Global Selfie" mosaic was built using more than 36,000 individual photographs drawn from the more than 50,000 images tagged #GlobalSelfie and posted on or around Earth Day, April 22, on Twitter, Instagram, Facebook, Google+ and Flickr. The project was designed to encourage environmental awareness and recognize the agency's ongoing work to protect our home planet.

Selfies were posted by people on every continent and 113 countries and regions, from Antarctica to Yemen, Greenland to Guatemala, and Pakistan to Peru. The resulting global mosaic is a zoomable 3.2-gigapixel image that users can scan and explore to look at individual photos. The Global Selfie was assembled after several weeks of collecting and curating the submitted images.

"With the Global Selfie, NASA used crowd-sourced digital imagery to illustrate a different aspect of Earth than has been measured from satellites for decades: a mosaic of faces from around the globe," said Peg Luce, deputy director of the Earth Science Division in the Science Mission Directorate at NASA Headquarters, Washington. "We were overwhelmed to see people participate from so many countries. We're very grateful that people took the time to celebrate our home planet together, and we look forward to everyone doing their part to be good stewards of our precious Earth."

The GigaPan image of Earth is based on views of each hemisphere captured on Earth Day 2014 by the Visible Infrared Imaging Radiometer Suite instrument on the Suomi National Polar-orbiting Partnership (NPP) satellite. Suomi NPP, a joint mission between NASA and the National Oceanic and Atmospheric Administration, collects data on both long-term climate change and short-term weather conditions.

The Global Selfie mosaic and related images and videos are available at:

http://go.nasa.gov/1n4y8qp

The Global Selfie is part of a special year for NASA Earth science. For the first time in more than a decade, five NASA Earth Science missions are scheduled to launch in one year. The Global Precipitation Measurement Core Observatory, a joint mission with the Japan Aerospace Exploration Agency, was launched in February. The Orbiting Carbon Observatory-2 is set to launch in July, with the Soil Moisture Active Passive mission to follow in November. And two Earth science instruments -- RapidScat and the Cloud-Aerosol Transport System -- will be launched to the International Space Station.

NASA missions have helped identify thousands of new planets across the universe in recent years, but the space agency studies no planet more closely than our own. With 17 Earth-observing satellites in orbit and ambitious airborne and ground-based observation campaigns, NASA produces data that help scientists get a clearer picture of Earth's interconnected natural systems. The agency shares this unique knowledge with the global community and works with institutions in the United States and around the world that contribute to understanding and protecting our home planet.

For more information about NASA's Earth science activities in 2014, visit:

http://www.nasa.gov/earthrightnow

Alan Buis

Jet Propulsion Laboratory, Pasadena, Calif.

818-354-0474

alan.buis@jpl.nasa.gov


Steve Cole

NASA Headquarters, Washington

202-358-0918

stephen.e.cole@nasa.gov


2014-161
Posted by Nelio Inacio at 8:08 AM 0 comments

Sunsets on Titan Reveal the Complexity of Hazy Exoplanets

Sunsets on Titan Reveal the Complexity of Hazy Exoplanets:

Artist's rendering of NASA's Cassini spacecraft
Artist's rendering of NASA's Cassini spacecraft observing a sunset through Titan's hazy atmosphere. Image credit: NASA/JPL-Caltech
› Full image and caption


May 27, 2014

Scientists working with data from NASA's Cassini mission have developed a new way to understand the atmospheres of exoplanets by using Saturn's smog-enshrouded moon Titan as a stand-in. The new technique shows the dramatic influence that hazy skies could have on our ability to learn about these alien worlds orbiting distant stars.

The work was performed by a team of researchers led by Tyler Robinson, a NASA Postdoctoral Research Fellow at NASA's Ames Research Center in Moffett Field, California. The findings were published May 26 in the Proceedings of the National Academy of Sciences.

"It turns out there's a lot you can learn from looking at a sunset," Robinson said.

Light from sunsets, stars and planets can be separated into its component colors to create spectra, as prisms do with sunlight, in order to obtain hidden information. Despite the staggering distances to other planetary systems, in recent years researchers have begun to develop techniques for collecting spectra of exoplanets. When one of these worlds transits, or passes in front of its host star as seen from Earth, some of the star's light travels through the exoplanet's atmosphere, where it is changed in subtle, but measurable, ways. This process imprints information about the planet that can be collected by telescopes. The resulting spectra are a record of that imprint.

Spectra enable scientists to tease out details about what exoplanets are like, such as aspects of the temperature, composition and structure of their atmospheres.

Robinson and his colleagues exploited a similarity between exoplanet transits and sunsets witnessed by the Cassini spacecraft at Titan. These observations, called solar occultations, effectively allowed the scientists to observe Titan as a transiting exoplanet without having to leave the solar system. In the process, Titan's sunsets revealed just how dramatic the effects of hazes can be.

Multiple worlds in our own solar system, including Titan, are blanketed by clouds and high-altitude hazes. Scientists expect that many exoplanets would be similarly obscured. Clouds and hazes create a variety of complicated effects that researchers must work to disentangle from the signature of these alien atmospheres, and thus present a major obstacle for understanding transit observations. Due to the complexity and computing power required to address hazes, models used to understand exoplanet spectra usually simplify their effects.

"Previously, it was unclear exactly how hazes were affecting observations of transiting exoplanets," said Robinson. "So we turned to Titan, a hazy world in our own solar system that has been extensively studied by Cassini."

The team used four observations of Titan made between 2006 and 2011 by Cassini's visual and infrared mapping spectrometer instrument. Their analysis provided results that include the complex effects due to hazes, which can now be compared to exoplanet models and observations.

With Titan as their example, Robinson and colleagues found that hazes high above some transiting exoplanets might strictly limit what their spectra can reveal to planet transit observers. The observations might be able to glean information only from a planet's upper atmosphere. On Titan, that corresponds to about 90 to 190 miles (150 to 300 kilometers) above the moon's surface, high above the bulk of its dense and complex atmosphere.

An additional finding from the study is that Titan's hazes more strongly affect shorter wavelengths, or bluer, colors of light. Studies of exoplanet spectra have commonly assumed that hazes would affect all colors of light in similar ways. Studying sunsets through Titan's hazes has revealed that this is not the case.

"People had dreamed up rules for how planets would behave when seen in transit, but Titan didn't get the memo," said Mark Marley, a co-author of the study at NASA Ames. "It looks nothing like some of the previous suggestions, and it's because of the haze."

The team's technique applies equally well to similar observations taken from orbit around any world, not just Titan. This means that researchers could study the atmospheres of planets like Mars and Saturn in the context of exoplanet atmospheres as well.

"It's rewarding to see that Cassini's study of the solar system is helping us to better understand other solar systems as well," said Curt Niebur, Cassini program scientist at NASA Headquarters in Washington.

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

More information about Cassini is available at the following sites:

http://www.nasa.gov/cassini

http://saturn.jpl.nasa.gov

Preston Dyches
818-354-5011

Jet Propulsion Laboratory, Pasadena, California

preston.dyches@jpl.nasa.gov

Michele Johnson

650-604-6982

NASA's Ames Research Center, Moffett Field, California

michele.johnson@nasa.gov


2014-164
Posted by Nelio Inacio at 8:07 AM 0 comments

The 'Serpent' Star-forming Cloud Hatches New Stars

The 'Serpent' Star-forming Cloud Hatches New Stars:

Within the swaddling dust of the Serpens Cloud Core
Within the swaddling dust of the Serpens Cloud Core, astronomers are studying one of the youngest collections of stars ever seen in our galaxy. Image credit: NASA/JPL-Caltech/2MASS
› Full image and caption


May 28, 2014

Stars that are just beginning to coalesce out of cool swaths of dust and gas are showcased in this image from NASA's Spitzer Space Telescope and the Two Micron All Sky Survey (2MASS). Infrared light has been assigned colors we see with our eyes, revealing young stars in orange and yellow, and a central parcel of gas in blue. This area is hidden in visible-light views, but infrared light can travel through the dust, offering a peek inside the stellar hatchery.

The dark patch to the left of center is swaddled in so much dust, even the infrared light is blocked. It is within these dark wombs that stars are just beginning to take shape.

Called the Serpens Cloud Core, this star-forming region is located about 750 light-years away in Serpens, or the "Serpent," a constellation named after its resemblance to a snake in visible light. The region is noteworthy as it only contains stars of relatively low to moderate mass, and lacks any of the massive and incredibly bright stars found in larger star-forming regions like the Orion nebula. Our sun is a star of moderate mass. Whether it formed in a low-mass stellar region like Serpens, or a high-mass stellar region like Orion, is an ongoing mystery.

The inner Serpens Cloud Core is remarkably detailed in this image. It was assembled from 82 snapshots representing a whopping 16.2 hours of Spitzer observing time. The observations were made during Spitzer's "warm mission," a phase that began in 2009 after the observatory ran out of liquid coolant, as planned.

Most of the small dots in this image are stars located behind, or in front of, the Serpens nebula.

The 2MASS mission was a joint effort between the California Institute of Technology, Pasadena; the University of Massachusetts, Amherst; and NASA's Jet Propulsion Laboratory, also in Pasadena.

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


2014-166
Posted by Nelio Inacio at 8:07 AM 0 comments

NASA Coverage for Saucer-Shaped Test Vehicle Flight

NASA Coverage for Saucer-Shaped Test Vehicle Flight:

A saucer-shaped test vehicle holding equipment for landing large payloads on Mars
A saucer-shaped test vehicle holding equipment for landing large payloads on Mars is shown in the Missile Assembly Building at the US Navy's Pacific Missile Range Facility in Kaua'i, Hawaii. Image Credit: NASA/JPL-Caltech
› Full image and caption


May 29, 2014

NASA's Low-Density Supersonic Decelerator (LDSD) project will fly a rocket-powered, saucer-shaped test vehicle into near-space next week from the U.S. Navy's Pacific Missile Range Facility in Kauai, Hawaii.

On Monday, June 2, a televised news conference about the test will be held at the PMRF at 8 a.m. Hawaii Standard Time (11 a.m. Pacific Daylight Time/2 p.m. Eastern Daylight Time).

Briefing panelists include:

-- U.S. Navy Capt. Bruce Hay, PMRF Commanding Officer

-- Mike Gazarik, associate administrator of the Space Technology Mission Directorate at NASA Headquarters, Washington

--Mark Adler, LDSD project manager at NASA's Jet Propulsion Laboratory (JPL) in Pasadena, California

--Ian Clark, LDSD principal investigator at JPL

NASA has identified six potential dates for launch of the high-altitude balloon carrying the LDSD experiment: June 3, 5, 7, 9, 11 and 14. Decisions to attempt launch of the LDSD test will be made the day before each launch opportunity date. NASA will issue launch advisories via the mission website, advisories and on Twitter at:

https://twitter.com/NASA_Technology

and

https://twitter.com/NASA

On launch attempt days, journalists are invited to PMRF to watch the liftoff and flight of the balloon carrying the LDSD. June 3 is the first launch attempt day, with a launch window extending from 8 to 9:30 a.m. HST (11 to 12:30 PDT/2 to 3:30 EDT).

NASA's LDSD carries several onboard cameras. It is expected that video of selected portions, including the rocket-powered ascent, will be downlinked live and streamed live to NASA TV and online.

The public may watch the news conference on June 2, and the balloon launch and subsequent test on June 3, on NASA TV or on the Web at:

http://www.nasa.gov/nasatv

and

http://www.ustream.tv/nasajpl2

Live commentary is expected to begin at 7:45 a.m. Hawaii Standard Time (10:45 a.m. PDT/1:45 p.m. EDT). For NASA TV streaming video, downlink and updated scheduling information, visit:

http://www.nasa.gov/nasatv

After the balloon reaches an altitude of 120,000 feet, the rocket-powered test vehicle will be dropped. Seconds later, its motor will fire, carrying it to 180,000 feet and as fast as about Mach 3.8.

More information about the LDSD space technology demonstration mission is online at:

http://go.usa.gov/kzZQ

NASA's Space Technology Mission Directorate funds the LDSD mission, a cooperative effort led by JPL. NASA's Marshall Space Flight Center in Huntsville, Alabama, manages LDSD within the Technology Demonstration Mission Program Office. NASA's Wallops Flight Facility in Wallops Island, Virginia, is coordinating support with the Pacific Missile Range Facility and providing the balloon systems for the LDSD test.

For more information about the Space Technology Mission Directorate, visit:

http://www.nasa.gov/spacetech

David Steitz

NASA Headquarters, Washington

202-236-5829

david.steitz@nasa.gov


DC Agle

Jet Propulsion Laboratory, Pasadena, Calif.

818-393-9011

agle@jpl.nasa.gov



Stefan Alford

Pacific Missile Range Facility, Kauai, Hawaii

808-335-4740

stefan.alford@navy.mil


2014-168
Posted by Nelio Inacio at 8:05 AM 0 comments

NASA's 'Flying Saucer' Readies for First Test Flight

NASA's 'Flying Saucer' Readies for First Test Flight:

LDSD's Rocket-powered Test Vehicle
This artist's concept shows the test vehicle for NASA's Low-Density Supersonic Decelerator (LDSD), designed to test landing technologies for future Mars missions. Image credit: NASA/JPL-Caltech

› Full image and caption


June 12, 2014

9th Update 12:30 PM PDT


NASA did not conduct the flight test of the agency's Low-Density Supersonic Decelerator (LDSD) from the U.S. Navy's Pacific Missile Range in Kauai, Hawaii, during its designated launch period. The project's reserved time at the range will expire Saturday, June 14, with NASA unable to fly the test because of continuing unfavorable weather conditions.



Mark Adler, the Low Density Supersonic Decelerator project manager and Ian
Clark, principal investigator on the project, both from NASA's Jet Propulsion Laboratory in Pasadena, California, participated in a media teleconference this morning and addressed questions on the project.



"There were six total opportunities to test the vehicle, and the delay of all six opportunities was caused by weather," said Adler. "We needed the mid-level winds between 15,000 and 60,000 feet to take the balloon away from the island. While there were a few days that were very close, none of the days had the proper wind conditions."



The team had researched for more than two years wind conditions and locations around the world that would be conducive to the test. Kauai was selected because research showed that this area had the proper wind conditions to carry the balloon away from populated areas and where it needed to go over the ocean in order to launch the test vehicle. Recent weather conditions have been unexpected and have caused unacceptable wind conditions to launch the balloon.



NASA continues to look at options for a future launch window. The team is working with the Pacific Missile Range Facility and looking at weather conditions predicted for later in the month when another launch window could be possible.



"Our team has been working on this project for several years, and we have been so focused," said Clark. "We came here to do our job and get this vehicle off the ground, but unfortunately weather didn't allow us to do this. We are very optimistic and are hoping to test the vehicle at the end of the month."



NASA's Space Technology Mission Directorate in Washington funds the LDSD mission, a cooperative effort led by JPL. NASA's Marshall Space Flight Center in Huntsville, Alabama, manages LDSD within the Technology Demonstration Mission Program Office. NASA's Wallops Flight Facility in Virginia is coordinating support with the Pacific Missile Range Facility and providing the balloon systems for the LDSD test.



Continue to follow us here and also on Twitter: @NASA_Technology, @NASA,
@NASAJPL and @NASA_Marshall for the latest updates on the mission.


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8th Update 3:00 PM PDT

NASA's Low Density Supersonic Decelerator will not launch Saturday, June 14, due to unfavorable weather conditions forecast for this last designated launch date in the current launch period. NASA will research range availability for the coming weeks and the costs associated with extending the test flight period for launching LDSD's high-altitude balloon and test vehicle, with programmatic decisions required to proceed.


We will hold a teleconference for media with LDSD project representatives with the date and time still being decided, more than likely tomorrow morning. As soon as we have that information confirmed, we will send a media advisory with date, time and call-in information.


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7th Update 7:02 PM PDT

Due to weather conditions, there will be no launch of the LDSD test vehicle today, Wednesday, June 11. The next potential launch date is Saturday, June 14.


Check back on our website and @NASA_Technology to get the latest updates on the mission.


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6th Update 9:21 PM PDT

Mission managers are proceeding with preparations for a launch attempt Wednesday morning, June 11, of a high-altitude balloon carrying the LDSD test vehicle to the edge of space on a test flight of the "flying saucer." At present, weather forecasted for the morning is close, but not within launch parameters. Mission managers will evaluate the latest weather conditions again early in the morning, to confirm favorable conditions. The Wednesday launch window extends from 8:15 a.m. to 9 a.m. HST (11:15 a.m. to 12 noon PDT).


Check back on our website and @NASA_Technology to get the latest updates on the mission.


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5th Update 6:12 PM PDT

The winds aren't cooperating for our launch of the Low Density Supersonic Decelerator (LDSD) tomorrow, Monday, June 9. Other potential launch dates include June 11 and 14. Wind conditions have been the prevailing factor in the launch delays, as they have to be just the right speed and direction in order to launch the balloon that carries the LDSD test vehicle. The launch decision for Wednesday, June 11 will be made on Tuesday, June 10. Check back with us for updates.


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4th Update 3:06 PM PDT

Due to weather conditions, there will be no launch of the LDSD test vehicle tomorrow, Saturday, June 7. Other potential launch dates include June 9, 11, and 14. Launch decision for Monday, June 9 will be made on Sunday, June 8. Check back with us for updates.


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3rd Update 4:20 PM PDT

Due to weather conditions, there will be no launch of the LDSD test vehicle Thursday, June 5. Other potential launch dates include June 7, 9, 11 and 14. The decision to move forward with another launch attempt of the LDSD test is made the day before each launch opportunity date.


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2nd Update 5:30 PM PDT

Due to weather conditions, there will be no launch of the LDSD test vehicle Tuesday, June 3. Other potential launch dates include June 5, 7, 9, 11 and 14. Launch decision for Thursday, June 5 will be made on Wednesday, June 4. Check back with us for updates.


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NASA's flying saucer-shaped test vehicle is ready to take to the skies from the U.S. Navy's Pacific Missile Range Facility in Kauai, Hawaii, for its first engineering shakeout flight.

The first launch opportunity for the test vehicle is June 3, when the launch window opens at 8:30 a.m. Hawaii Standard Time (11:30 a.m. PDT/2:30 p.m. EDT). The test will be carried live on NASA TV and streamed on the Web. The Low Density Supersonic Decelerator (LDSD) will gather data about landing heavy payloads on Mars and other planetary surfaces.

"The agency is moving forward and getting ready for Mars as part of NASA's Evolvable Mars campaign," said Michael Gazarik, associate administrator for Space Technology at NASA Headquarters in Washington. "We fly, we learn, we fly again. We have two more vehicles in the works for next year."

As NASA plans increasingly ambitious robotic missions to Mars, laying the groundwork for even more complex human science expeditions to come, accommodating extended stays for explorers on the Martian surface will require larger and heavier spacecraft.

The objective of the LDSD project is to see if the cutting-edge, rocket-powered test vehicle operates as it was designed -- in near-space at high Mach numbers.

"After years of imagination, engineering and hard work, we soon will get to see our Keiki o ka honua, our 'boy from Earth,' show us its stuff," said Mark Adler, project manager for the Low Density Supersonic Decelerator at NASA's Jet Propulsion Laboratory in Pasadena, California. "The success of this experimental test flight will be measured by the success of the test vehicle to launch and fly its flight profile as advertised. If our flying saucer hits its speed and altitude targets, it will be a great day."

The way NASA's saucer climbs to test altitude is almost as distinctive as the test vehicle itself.

"We use a helium balloon -- that, when fully inflated, would fit snugly into Pasadena's Rose Bowl -- to lift our vehicle to 120,000 feet," said Adler. "From there we drop it for about one-and-a-half seconds. After that, it's all about going higher and faster -- and then it's about putting on the brakes."

A fraction of a second after dropping from the balloon, and a few feet below it, four small rocket motors will fire to spin up and gyroscopically stabilize the saucer. A half second later, a Star 48B long-nozzle, solid-fueled rocket engine will kick in with 17,500 pounds of thrust, sending the test vehicle to the edge of the stratosphere.

"Our goal is to get to an altitude and velocity which simulates the kind of environment one of our vehicles would encounter when it would fly in the Martian atmosphere," said Ian Clark, principal investigator of the LDSD project at JPL. "We top out at about 180,000 feet and Mach 4. Then, as we slow down to Mach 3.8, we deploy the first of two new atmospheric braking systems."

The project management team decided also to fly the two supersonic decelerator technologies that will be thoroughly tested during two LDSD flight tests next year.

If this year's test vehicle flies as expected, the LDSD team may get a treasure-trove of data on how the approximately 20-foot (6-meter) supersonic inflatable aerodynamic decelerator (SIAD-R) and the supersonic parachute operate a full year ahead of schedule.

The SIAD-R, essentially an inflatable doughnut that increases the vehicle's size and, as a result, its drag, is deployed at about Mach 3.8. It will quickly slow the vehicle to Mach 2.5 where the parachute, the largest supersonic parachute ever flown, first hits the supersonic flow. About 45 minutes later, the saucer is expected to make a controlled landing onto the Pacific Ocean off Hawaii.

NASA TV will carry live images and commentary of LDSD engineering test. The test vehicle itself carries several onboard cameras. It is expected that video of selected portions of the test, including the rocket-powered ascent, will be downlinked during the commentary. Websites streaming live video of the test include:

http://www.nasa.gov/nasatv and http://www.ustream.tv/nasajpl2

For more information about LDSD, visit: http://www.nasa.gov/mission_pages/tdm/ldsd/

NASA's Space Technology Mission Directorate in Washington funds the LDSD mission, a cooperative effort led by JPL. NASA's Marshall Space Flight Center in Huntsville, Alabama, manages LDSD within the Technology Demonstration Mission Program Office. NASA's Wallops Flight Facility in Virginia is coordinating support with the Pacific Missile Range Facility and providing the balloon systems for the LDSD test.

DC Agle

Jet Propulsion Laboratory, Pasadena, Calif.

818-393-9011

agle@jpl.nasa.gov


David Steitz

NASA Headquarters, Washington

202-358-1730

david.steitz@nasa.gov


Stefan Alford

Pacific Missile Range Facility, Kauai, Hawaii

808-335-4740

stefan.alford@navy.mil


2014-169
Posted by Nelio Inacio at 7:58 AM 0 comments

Astronomers Confounded By Massive Rocky World

Astronomers Confounded By Massive Rocky World:

Kepler-10 system
An artist's conception shows the Kepler-10 system, home to two rocky planets. In the foreground is Kepler-10c, a planet that weighs 17 times as much as Earth and is more than twice as large in size. Planet formation theorists are challenged to explain how such a massive world could have formed. Credit: Harvard-Smithsonian Center for Astrophysics/David Aguilar

› Full image and caption


June 02, 2014

Astronomers have discovered a rocky planet that weighs 17 times as much as Earth and is more than twice as large in size. This discovery has planet formation theorists challenged to explain how such a world could have formed.

"We were very surprised when we realized what we had found," said astronomer Xavier Dumusque of the Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts, who led the analysis using data originally collected by NASA's Kepler space telescope.

Kepler-10c, as the planet had been named, had a previously measured size of 2.3 times larger than Earth, but its mass was not known until now. The team used the HARPS-North instrument on the Telescopio Nazionale Galileo in the Canary Islands to conduct follow-up observations to obtain a mass measurement of the rocky behemoth.

It was thought worlds such as this could not possibly exist. The enormous gravitational force of such a massive body would accrete a gas envelope during formation, ballooning the planet to a gas giant the size of Neptune or even Jupiter. However, this planet is thought to be solid, composed primarily of rock.

"Just when you think you've got it all figured out, nature gives you a huge surprise -- in this case, literally," said Natalie Batalha, Kepler mission scientist at NASA's Ames Research Center in Moffett Field, California. "Isn't science marvelous?"

Kepler-10c orbits a sun-like star every 45 days, making it too hot to sustain life as we know it. It is located about 560 light-years from Earth in the constellation Draco. The system also hosts Kepler-10b, the first rocky planet discovered in the Kepler data.

The finding was presented today at a meeting of the American Astronomical Society in Boston. Read more about the discovery in the Harvard-Smithsonian Center for Astrophysics news release.

NASA's Ames Research Center manages Kepler's ground system development, mission operations and science data analysis. NASA's Jet Propulsion Laboratory, Pasadena, California, managed the Kepler mission's development.

Ball Aerospace and Technologies Corp. in Boulder, Colorado, developed the Kepler flight system and supports mission operations with the Laboratory for Atmospheric and Space Physics at the University of Colorado in Boulder.

The Space Telescope Science Institute in Baltimore archives, hosts and distributes Kepler science data. Kepler is NASA's 10th Discovery Mission and is funded by NASA's Science Mission Directorate at the agency's headquarters in Washington.

For more information about the Kepler mission, visit:

http://www.nasa.gov/kepler

For more information about exoplanets and NASA's planet-finding program, visit:

http://planetquest.jpl.nasa.gov

Whitney Clavin 818-354-4673

Jet Propulsion Laboratory, Pasadena, Calif.

whitney.clavin@jpl.nasa.gov


2014-171
Posted by Nelio Inacio at 7:45 AM 0 comments

Herschel Sees Budding Stars and a Giant, Strange Ring

Herschel Sees Budding Stars and a Giant, Strange Ring:

A Puzzling Cosmic Ring
The Herschel Space Observatory has uncovered a weird ring of dusty material while obtaining one of the sharpest scans to date of a huge cloud of gas and dust, called NGC 7538. Image credit: ESA/NASA/JPL-Caltech/Whitman College
› Full image and caption


June 12, 2014

The Herschel Space Observatory has uncovered a weird ring of dusty material while obtaining one of the sharpest scans to date of a huge cloud of gas and dust, called NGC 7538. The observations have revealed numerous clumps of material, a baker's dozen of which may evolve into the most powerful kinds of stars in the universe. Herschel is a European Space Agency mission with important NASA contributions.

"We have looked at NGC 7538 with Herschel and identified 13 massive, dense clumps where colossal stars could form in the future," said paper lead author Cassandra Fallscheer, a visiting assistant professor of astronomy at Whitman College in Walla Walla, Washington, and lead author of the paper published in The Astrophysical Journal. "In addition, we have found a gigantic ring structure and the weird thing is, we're not at all sure what created it."

NGC 7538 is relatively nearby, at a distance of about 8,800 light-years and located in the constellation Cepheus. The cloud, which has a mass on the order of 400,000 suns, is undergoing an intense bout of star formation. Astronomers study stellar nurseries such as NGC 7538 to better learn how stars come into being. Finding the mysterious ring, in this case, came as an unexpected bonus.

The cool, dusty ring has an oval shape, with its long axis spanning about 35 light-years and its short axis about 25 light-years. Fallscheer and her colleagues estimate that the ring possesses the mass of 500 suns. Additional data from the James Clerk Maxwell Telescope, located at the Mauna Kea Observatory in Hawaii, further helped characterize the odd ovoid. Astronomers often see ring and bubble-like structures in cosmic dust clouds. The strong winds cast out by the most massive stars, called O-type stars, can generate these expanding puffs, as can their explosive deaths as supernovas. But no energetic source or remnant of a deceased O-type star, such as a neutron star, is apparent within the center of this ring. It is possible that a big star blew the bubble and, because stars are all in motion, subsequently left the scene, escaping detection.

The observations were taken as part of the Herschel OB Young Stellar objects (HOBYS) Key Programme. The "OB" refers to the two most massive kinds of stars, O-type and B-type. These bright blue, superhot, short-lived stars end up exploding as supernovas, leaving behind either incredibly dense neutron stars or even denser black holes.

Stars of this caliber form from gassy, dusty clumps with initial masses dozens of times greater than the sun's; the 13 clumps spotted in NGC 7358, some of which lie along the edge of the mystery ring, all are more than 40 times more massive than the sun. The clumps gravitationally collapse in on themselves, growing denser and hotter in their cores until nuclear fusion ignites and a star is born. For now, early in the star-formation process, the clumps remain quite cold, just a few tens of degrees above absolute zero. At these temperatures, the clumps emit the bulk of their radiation in the low-energy, submillimeter and infrared light that Herschel was specifically designed to detect.

As astronomers continue probing these budding O-type giants in NGC 7358, the follow-up observations with other telescopes should also help in solving the puzzle of the humongous, dusty ring. "Further research to determine the mechanism responsible for creating the ring structure is necessary," said Fallscheer.

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

More information is online at:

http://www.herschel.caltech.edu

http://www.nasa.gov/herschel

http://www.esa.int/SPECIALS/Herschel

Whitney Clavin 818-354-4673

Jet Propulsion Laboratory, Pasadena, Calif.

whitney.clavin@jpl.nasa.gov


2014-189
Posted by Nelio Inacio at 7:44 AM 0 comments

Giant Telescopes Pair Up to Image Near-Earth Asteroid

Giant Telescopes Pair Up to Image Near-Earth Asteroid:

Radar images of Asteroid 2014 HQ124
NASA scientists used Earth-based radar to produce these sharp views - an image montage and a movie sequence -- of the asteroid designated '2014 HQ124' on June 8, 2014. Image Credit: NASA/JPL-Caltech/Arecibo Observatory/USRA/NSF
› Full image and caption


June 12, 2014

NASA scientists using Earth-based radar have produced sharp views of a recently discovered asteroid as it slid silently past our planet. Captured on June 8, 2014, the new views of the object designated "2014 HQ124" are some of the most detailed radar images of a near-Earth asteroid ever obtained.

An animation of the rotating asteroid and a collage of the images are available at:

http://www.jpl.nasa.gov/video/index.php?id=1310

The radar observations were led by scientists Marina Brozovic and Lance Benner of NASA's Jet Propulsion Laboratory, Pasadena, California. The JPL researchers worked closely with Michael Nolan, Patrick Taylor, Ellen Howell and Alessondra Springmann at Arecibo Observatory in Puerto Rico to plan and execute the observations.

According to Benner, 2014 HQ124 appears to be an elongated, irregular object that is at least 1,200 feet (370 meters) wide on its long axis. "This may be a double object, or 'contact binary,' consisting of two objects that form a single asteroid with a lobed shape," he said. The images reveal a wealth of other features, including a puzzling pointy hill near the object's middle, on top as seen in the images.

The 21 radar images were taken over a span of four-and-a-half hours. During that interval, the asteroid rotated a few degrees per frame, suggesting its rotation period is slightly less than 24 hours.

At its closest approach to Earth on June 8, the asteroid came within 776,000 miles (1.25 million kilometers), or slightly more than three times the distance to the moon. Scientists began observations of 2014 HQ124 shortly after the closest approach, when the asteroid was between about 864,000 miles and 902,000 miles (1.39 million kilometers and 1.45 million kilometers) from Earth.

Each image in the collage and movie represents 10 minutes of data.

The new views show features as small as about 12 feet (3.75 meters) wide. This is the highest resolution currently possible using scientific radar antennas to produce images. Such sharp views for this asteroid were made possible by linking together two giant radio telescopes to enhance their capabilities.

To obtain the new views, researchers paired the 230-foot (70-meter) Deep Space Network antenna at Goldstone, California, with two other radio telescopes, one at a time. Using this technique, the Goldstone antenna beams a radar signal at an asteroid and the other antenna receives the reflections. The technique dramatically improves the amount of detail that can be seen in radar images.

To image 2014 HQ124, the researchers first paired the large Goldstone antenna with the 1,000-foot (305-meter) Arecibo radio telescope in Puerto Rico. They later paired the large Goldstone dish with a smaller companion, a 112-foot (34-meter) antenna, located about 20 miles (32 kilometers) away.

A recent equipment upgrade at Arecibo enabled the two facilities to work in tandem to obtain images with this fine level of detail for the first time.

"By itself, the Goldstone antenna can obtain images that show features as small as the width of a traffic lane on the highway," said Benner. "With Arecibo now able to receive our highest-resolution Goldstone signals, we can create a single system that improves the overall quality of the images."

The first five images in the new sequence -- the top row in the collage -- represent the data collected by Arecibo, and are 30 times brighter than what Goldstone can produce observing on its own.

Scientists were fortunate to be able to make these radar observations at all, as this particular asteroid was only recently discovered. NASA's NEOWISE mission, a space telescope adapted for scouting the skies for the infrared light emitted by asteroids and comets, first spotted the space rock on April 23, 2014. Additional information about the asteroid's discovery and its orbit was shared in a previous Web story online at:

http://www.jpl.nasa.gov/news/news.php?release=2014-178

For asteroids, as well as comets, radar is a powerful tool for studying the objects' size, shape, rotation, surface features and orbits. Radar measurements of asteroid distances and velocities enable researchers to compute orbits much further into the future than if radar observations were not available.

NASA detects, tracks and characterizes asteroids and comets passing close to Earth using both ground- and space-based telescopes. The Near-Earth Object Program, commonly called "Spaceguard," discovers these objects, characterizes a subset of them and identifies their orbits to determine if any could be potentially hazardous to our planet. To date, U.S. assets have discovered more than 98 percent of the known near-Earth objects.

Along with the resources NASA puts into understanding asteroids, it also partners with other U.S. government agencies, university-based astronomers and space science institutes across the country that are working to find, track and understand these objects better, often with grants, interagency transfers and other contracts from NASA. In addition, NASA values the work of numerous highly skilled amateur astronomers, whose accurate observational data helps improve asteroid orbits after they are found.

The contributions of JPL engineers Jon Giorgini, Joseph Jao and Clement Lee were critical to the successful execution of these observations.

Through its Asteroid Initiative, NASA is developing a first-ever mission to identify, capture and redirect a near-Earth asteroid to a stable orbit around the moon with a robotic spacecraft. Astronauts aboard an Orion spacecraft, launched by a Space Launch System rocket, will explore the asteroid in the 2020s, returning to Earth with samples. Experience in human spaceflight beyond low-Earth orbit through this Asteroid Redirect Mission will help NASA test new systems and capabilities needed to support future human missions to Mars. The Initiative also includes an Asteroid Grand Challenge, which is seeking the best ideas to find all asteroid threats to human populations and accelerate the work NASA already is doing for planetary defense.

JPL manages the Near-Earth Object Program Office for NASA's Science Mission Directorate in Washington. JPL is a division of the California Institute of Technology in Pasadena.

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

http://neo.jpl.nasa.gov/

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

Twitter updates are at:

http://www.twitter.com/asteroidwatch

Preston Dyches 818-354-7013

Jet Propulsion Laboratory, Pasadena, Calif.

preston.dyches@jpl.nasa.gov


2014-186
Posted by Nelio Inacio at 7:42 AM 0 comments

New NASA Space Observatory to Study Carbon Conundrums

New NASA Space Observatory to Study Carbon Conundrums:

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


June 12, 2014

NASA's first spacecraft dedicated to measuring carbon dioxide levels in Earth's atmosphere is in final preparations for a July 1 launch from Vandenberg Air Force Base, California.

The Orbiting Carbon Observatory-2 (OCO-2) mission will provide a more complete, global picture of the human and natural sources of carbon dioxide, as well as carbon dioxide's "sinks," the natural ocean and land processes by which carbon dioxide is pulled out of Earth's atmosphere and stored. Carbon dioxide, a critical component of Earth's carbon cycle, is the leading human-produced greenhouse gas driving changes in Earth's climate.

"Carbon dioxide in the atmosphere plays a critical role in our planet's energy balance and is a key factor in understanding how our climate is changing," said Michael Freilich, director of NASA's Earth Science Division in Washington. "With the OCO-2 mission, NASA will be contributing an important new source of global observations to the scientific challenge of better understanding our Earth and its future."

OCO-2 will launch on a United Launch Alliance Delta II rocket and maneuver into a 438-mile (705-kilometer) altitude, near-polar orbit. It will become the lead satellite in a constellation of five other international Earth monitoring satellites that circle Earth once every 99 minutes and cross the equator each day near 1:36 p.m. local time, making a wide range of nearly simultaneous Earth observations. OCO-2 is designed to operate for at least two years.

The spacecraft will sample the global geographic distribution of the sources and sinks of carbon dioxide and allow scientists to study their changes over time more completely than can be done with any existing data. Since 2009, Earth scientists have been preparing for OCO-2 by taking advantage of observations from the Japanese GOSAT satellite. OCO-2 replaces a nearly identical NASA spacecraft lost because of a rocket launch mishap in February 2009.

At approximately 400 parts per million, atmospheric carbon dioxide is now at its highest level in at least the past 800,000 years. The burning of fossil fuels and other human activities are currently adding nearly 40 billion tons of carbon dioxide to the atmosphere each year, producing an unprecedented buildup in this greenhouse gas.

Greenhouse gases trap the sun's heat within Earth's atmosphere, warming the planet's surface and helping to maintain habitable temperatures from the poles to the equator. Scientists have concluded increased carbon dioxide from human activities, particularly fossil fuel burning and deforestation, has thrown Earth's natural carbon cycle off balance, increasing global surface temperatures and changing our planet's climate.

Currently, less than half the carbon dioxide emitted into Earth's atmosphere by human activities stays there. Some of the remainder is absorbed by Earth's ocean, but the location and identity of the natural land sinks believed to be absorbing the rest are not well understood. OCO-2 scientists hope to coax these sinks out of hiding and resolve a longstanding scientific puzzle.

"Knowing what parts of Earth are helping remove carbon from our atmosphere will help us understand whether they will keep doing so in the future," said Michael Gunson, OCO-2 project scientist at NASA's Jet Propulsion Laboratory, Pasadena, California. "Understanding the processes controlling carbon dioxide in our atmosphere will help us predict how fast it will build up in the future. Data from this mission will help scientists reduce uncertainties in forecasts of how much carbon dioxide will be in the atmosphere and improve the accuracy of global climate change predictions."

OCO-2 measurements will be combined with data from ground stations, aircraft and other satellites to help answer questions about the processes that regulate atmospheric carbon dioxide and its role in Earth's climate and carbon cycle. Mission data will also help assess the usefulness of space-based measurements of carbon dioxide for monitoring emissions.

The observatory's science instrument features three high-resolution spectrometers that spread reflected sunlight into its component colors and then precisely measure the intensity of each color. Each spectrometer is optimized to record a different, specific color absorbed by carbon dioxide and oxygen molecules in Earth's atmosphere. The less carbon dioxide in the atmosphere, the more light the spectrometers detect. By analyzing the amount of light, scientists can estimate the relative concentrations of these chemicals.

The new observatory will dramatically increase the number of observations of carbon dioxide, collecting hundreds of thousands of measurements each day when the satellite flies over Earth's sunlit hemisphere. High-precision, detailed, near-global observations are needed to characterize carbon dioxide's distribution because the concentration of carbon dioxide varies by only a few percent throughout the year on regional to continental scales. Scientists will analyze the OCO-2 data, using computer models similar to those used to predict the weather, to locate and understand the sources and sinks of carbon dioxide.

OCO-2 is a NASA Earth System Science Pathfinder Program mission managed by JPL for NASA's Science Mission Directorate in Washington. Orbital Sciences Corporation in Dulles, Virginia, built the spacecraft bus and provides mission operations under JPL's leadership. The science instrument was built by JPL, based on the instrument design co-developed for the original OCO mission by Hamilton Sundstrand in Pomona, California. NASA's Launch Services Program at NASA's Kennedy Space Center in Florida is responsible for launch management. JPL is managed for NASA by the California Institute of Technology in Pasadena.

For more information about the Orbiting Carbon Observatory-2, visit:

http://oco.jpl.nasa.gov

and

http://www.nasa.gov/oco2

Follow OCO-2 on Twitter at:

https://twitter.com/IamOCO2

OCO-2 is the second of five NASA Earth science missions to be launched this year. NASA monitors Earth's vital signs from land, air and space with a fleet of satellites and ambitious airborne and ground-based observation campaigns. NASA develops new ways to observe and study Earth's interconnected natural systems with long-term data records and computer analysis tools to better see how our planet is changing. The agency shares this unique knowledge with the global community and works with institutions in the United States and around the world that contribute to understanding and protecting our home planet.

For more information about NASA's Earth science activities in 2014, visit:

http://www.nasa.gov/earthrightnow

Alan Buis

Jet Propulsion Laboratory, Pasadena, California

818-354-0474

alan.buis@jpl.nasa.gov


Steve Cole

NASA Headquarters, Washington

202-358-0918


2014-187
Posted by Nelio Inacio at 7:42 AM 0 comments

Herschel Sees Budding Stars and a Giant, Strange Ring

Herschel Sees Budding Stars and a Giant, Strange Ring:

A Puzzling Cosmic Ring
The Herschel Space Observatory has uncovered a weird ring of dusty material while obtaining one of the sharpest scans to date of a huge cloud of gas and dust, called NGC 7538. Image credit: ESA/NASA/JPL-Caltech/Whitman College
› Full image and caption


June 12, 2014

The Herschel Space Observatory has uncovered a weird ring of dusty material while obtaining one of the sharpest scans to date of a huge cloud of gas and dust, called NGC 7538. The observations have revealed numerous clumps of material, a baker's dozen of which may evolve into the most powerful kinds of stars in the universe. Herschel is a European Space Agency mission with important NASA contributions.

"We have looked at NGC 7538 with Herschel and identified 13 massive, dense clumps where colossal stars could form in the future," said paper lead author Cassandra Fallscheer, a visiting assistant professor of astronomy at Whitman College in Walla Walla, Washington, and lead author of the paper published in The Astrophysical Journal. "In addition, we have found a gigantic ring structure and the weird thing is, we're not at all sure what created it."

NGC 7538 is relatively nearby, at a distance of about 8,800 light-years and located in the constellation Cepheus. The cloud, which has a mass on the order of 400,000 suns, is undergoing an intense bout of star formation. Astronomers study stellar nurseries such as NGC 7538 to better learn how stars come into being. Finding the mysterious ring, in this case, came as an unexpected bonus.

The cool, dusty ring has an oval shape, with its long axis spanning about 35 light-years and its short axis about 25 light-years. Fallscheer and her colleagues estimate that the ring possesses the mass of 500 suns. Additional data from the James Clerk Maxwell Telescope, located at the Mauna Kea Observatory in Hawaii, further helped characterize the odd ovoid. Astronomers often see ring and bubble-like structures in cosmic dust clouds. The strong winds cast out by the most massive stars, called O-type stars, can generate these expanding puffs, as can their explosive deaths as supernovas. But no energetic source or remnant of a deceased O-type star, such as a neutron star, is apparent within the center of this ring. It is possible that a big star blew the bubble and, because stars are all in motion, subsequently left the scene, escaping detection.

The observations were taken as part of the Herschel OB Young Stellar objects (HOBYS) Key Programme. The "OB" refers to the two most massive kinds of stars, O-type and B-type. These bright blue, superhot, short-lived stars end up exploding as supernovas, leaving behind either incredibly dense neutron stars or even denser black holes.

Stars of this caliber form from gassy, dusty clumps with initial masses dozens of times greater than the sun's; the 13 clumps spotted in NGC 7358, some of which lie along the edge of the mystery ring, all are more than 40 times more massive than the sun. The clumps gravitationally collapse in on themselves, growing denser and hotter in their cores until nuclear fusion ignites and a star is born. For now, early in the star-formation process, the clumps remain quite cold, just a few tens of degrees above absolute zero. At these temperatures, the clumps emit the bulk of their radiation in the low-energy, submillimeter and infrared light that Herschel was specifically designed to detect.

As astronomers continue probing these budding O-type giants in NGC 7358, the follow-up observations with other telescopes should also help in solving the puzzle of the humongous, dusty ring. "Further research to determine the mechanism responsible for creating the ring structure is necessary," said Fallscheer.

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

More information is online at:

http://www.herschel.caltech.edu

http://www.nasa.gov/herschel

http://www.esa.int/SPECIALS/Herschel

Whitney Clavin 818-354-4673

Jet Propulsion Laboratory, Pasadena, Calif.

whitney.clavin@jpl.nasa.gov


2014-189
Posted by Nelio Inacio at 7:42 AM 0 comments

Titan Flybys Test the Talents of NASA's Cassini Team

Titan Flybys Test the Talents of NASA's Cassini Team:

Artist's concept of Titan flyby
Cassini will attempt to bounce signals off of Saturn's moon Titan once more during a flyby on June 18, 2014, revealing important details about the moon's surface. Image credit: NASA/JPL-Caltech
› Larger view


June 17, 2014

As NASA's Cassini spacecraft zooms toward Saturn's smoggy moon Titan for a targeted flyby on June 18, mission scientists are excitedly hoping to repeat a scientific tour de force that will provide valuable new insights into the nature of the moon's surface and atmosphere.

For Cassini's radio science team, the last flyby of Titan, on May 17, was one of the most scientifically valuable encounters of the spacecraft's current extended mission. The focus of that flyby, designated "T-101," was on using radio signals to explore the physical nature of Titan's vast northern seas and probe the high northern regions of its substantial atmosphere.

The Cassini team hopes to replicate the technical success of that flyby during the T-102 encounter, slated for June 18, during which the spacecraft will attempt similar measurements of Titan. During closest approach, the spacecraft will be just 2,274 miles (3,659 kilometers) above the surface of the moon while travelling at 13,000 miles per hour (5.6 kilometers per second).

During the upcoming flyby, if all goes well as before, Cassini's radio science subsystem will bounce signals off the surface of Titan, toward Earth, where they will be received by the ground stations of NASA's Deep Space Network. This sort of observation is known as a bistatic scattering experiment and its results can yield clues to help answer a variety of questions about large areas of Titan's surface: Are they solid, slushy or liquid? Are they reflective? What might they be made of?

During the May encounter, Cassini beamed radio signals over the two largest bodies of liquid on Titan, seas named Ligeia Mare and Kraken Mare. During that first attempt, scientists could not be certain the signals would successfully bounce off the lakes to be received on Earth. They were thrilled when ground stations received specular reflections -- essentially the glint -- of the radio frequencies as they ricocheted off Titan.

"We held our breath as Cassini turned to beam its radio signals at the lakes," said Essam Marouf, a member of the Cassini radio science team of San Jose State University in California. "We knew we were getting good quality data when we saw clear echoes from Titan's surface. It was thrilling."

A second technical accomplishment -- an experiment to send precision-tuned radio frequencies through Titan's atmosphere -- also makes the May and June flybys special. The experiment, known as a radio occultation, provides information about how temperatures vary by altitude in Titan's atmosphere. Preparing for these experiments tested just how thoroughly the Cassini team has come to understand the structure of Titan's atmosphere during nearly a decade of study by the mission.

During this type of radio occultation, a signal is beamed from Earth through the atmosphere of Titan toward the Cassini spacecraft, which responds back to Earth with an identical signal. Information about Titan is imprinted in the signal as it passes through the moon's atmosphere, encountering differences in temperature and density. The trick is that the transmitted signal must be varied during the experiment so that it remains nearly constant when received by the spacecraft.

In order to give the occultation experiments any chance of success, the team has to account for not only the relative motions of the spacecraft and the transmitting antennas on the rotating planet Earth, but also the ways the signal is bent by different layers in Titan's atmosphere.

While this procedure has been used successfully for several Saturn occultations in the past two years, it had not yet been tried at Titan. And since the Titan occultations last just a few minutes, the team was concerned about how quickly the frequency lockup between ground and spacecraft could be established, if at all. For comparison, NASA's Magellan mission tried the technique at Venus in the 1990s, without success.

As they waited for signs of confirmation during the May encounter, the team saw the signal lock occur in only a few seconds, indicating that their predictions were spot-on. Data on Titan's atmosphere flowed in, adding new information to the mission's campaign to monitor the changing of the seasons on this alien moon.

"This was like trying to hit a hole-in-one in golf, except that the hole is close to a billion miles away, and moving," said Earl Maize, Cassini project manager at NASA's Jet Propulsion Laboratory in Pasadena, California. "This was our first attempt to precisely predict and compensate for the effect of Titan's atmosphere on the uplinked radio signal from Earth, and it worked to perfection."

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. JPL, a division of the California Institute of Technology, Pasadena, manages the mission for NASA's Science Mission Directorate in Washington. The radio science team is based at JPL. NASA's Deep Space Network is also managed by JPL.

More information about Cassini is available at the following sites:

http://www.nasa.gov/cassini

http://saturn.jpl.nasa.gov

Preston Dyches

Jet Propulsion Laboratory, Pasadena, Calif.

818-354-7013

preston.dyches@jpl.nasa.gov



2014-192
Posted by Nelio Inacio at 7:41 AM 0 comments

QuikScat's Eye on Ocean Winds Lives On with RapidScat

QuikScat's Eye on Ocean Winds Lives On with RapidScat:

Using data from NASA's QuikScat, weather forecasters were able to predict hazardous weather events over oceans 6 to 12 hours earlier than before these data were available
Using data from NASA's QuikScat, weather forecasters were able to predict hazardous weather events over oceans 6 to 12 hours earlier than before these data were available. Orange areas show where winds are blowing the hardest and blue shows relatively light winds. Image credit: NASA


June 19, 2014

Today (June 19) marks the 15th anniversary of the launch of NASA's QuikScat, a satellite sent for a three-year mission in 1999 that continues collecting data. Built in less than 12 months, QuikScat has watched ocean wind patterns for 15 years and improved weather forecasting worldwide. Despite a partial instrument failure in 2009, it provides calibration data to international partners.

On this anniversary, the mission's team is preparing to calibrate ISS-RapidScat, the successor that will maintain QuikScat's unbroken data record. After its launch in a few months, RapidScat will watch ocean winds from the International Space Station (ISS) for a two-year mission.

Much like QuikScat, ISS-RapidScat was built in less than two years and at a fraction of its predecessor's budget. Both missions are testaments to ingenuity, craftsmanship and speedy construction in the name of improving our understanding of Earth's winds.

"Both ISS-RapidScat and QuikScat came about to react quickly to the failure of another spaceborne instrument," said Ernesto Rodriguez, project scientist for the ISS-RapidScat mission at NASA's Jet Propulsion Laboratory, Pasadena, California. "What differentiates these missions is cost and risk: RapidScat had to be built with a fraction of the QuikScat budget, and the mission accepted a much riskier approach," Rodriguez said. RapidScat was constructed primarily from QuikScat's spare parts and will be the first scatterometer to berth on the International Space Station.

Scatterometers help scientists estimate the speed and direction of winds at the ocean's surface by sending microwave pulses to Earth's surface. Strong waves or ripples scatter the microwaves, sending some of them back toward the scatterometer. Based on the strength of this backscatter, scientists can estimate the strength and direction of the wind at the ocean's surface.

Scatterometer data are critical for observing global weather patterns. They also help ocean fishermen decide where to fish, ship captains choose shipping lanes and researchers track hurricanes, cyclones and El Niños.

"The usefulness of this wind measurement is enormous," said JPL's Jim Graf, who served as project manager for the QuikScat mission in the 1990s and is now the deputy director of JPL's Earth Science and Technology Directorate. "One of the dominant factors in understanding the climate is to assess what is happening in the ocean circulation. And one of the dominant factors in ocean circulation is the wind at the surface, which is what scatterometers measure."

NASA launched its first scatterometer satellite in 1978 and its second instrument, the NASA Scatterometer (NSCAT), on a Japanese satellite in 1996. Each lasted less than a year, but collected hundreds of times more data about ocean winds than ships or buoys and improved weather forecasts from the National Oceanic and Atmospheric Administration (NOAA).

But the spacecraft carrying NSCAT malfunctioned in 1997. Immediately, a team of JPL scientists and engineers raced to get a scatterometer satellite back into space.

"We had the idea that a partially developed spacecraft bus could be mated with an advanced version of the instrument that was already under development, and we could get something up quickly. So we went to NASA, and they said, 'Okay, let's give it a shot, but we want you to be ready to go one year from the go-ahead,'" Graf said. "And so we took off running, and we didn't stop for a whole year."

In that year, Ball Aerospace & Technologies Corp., Boulder, Colorado, built the QuikScat satellite bus while JPL finished the new SeaWinds scatterometer instrument. It launched in 1999. For the next decade, QuikScat made about 400,000 daily measurements of wind speed and direction. Over 15-mile (25-kilometer) segments of ocean, its measurements were detailed enough to estimate average wind speed within 6 feet (2 meters) per second.

The SeaWinds instrument on QuikScat used a rotating antenna to measure a swath of Earth's surface 1,118 miles (1,800 kilometers) wide -- about the distance from Los Angeles to Seattle. As QuikScat flew, the rotations overlapped to cover more than 90 percent of Earth's surface every day.

But by the end of 2009, long after the expected end of QuikScat's mission, the lubricant coating the antenna's bearings dried up. Instead of tracing a round swath on Earth's surface, it pointed straight down and only watched the waves directly below it. Still, those data were sufficient to help calibrate newer satellites.

"Since 2009, we've been able to keep QuikScat operating quite successfully," said QuikScat Project Manager Rob Gaston of JPL. "We used QuikScat's highly successful backscatter measurements, which were well understood and had demonstrated stability, as a calibration standard for many instruments, including other scatterometers." The European Space Agency and Indian Space Research Organization have both used QuikScat data to calibrate scatterometers in the last five years.

QuikScat's final task will be to calibrate its successor, RapidScat. The satellite will continue collecting data until April 2015, when it will be decommissioned after nearly 16 years in orbit.

RapidScat, like QuikScat, was built in a fraction of the timeline for most missions. The two missions even share hardware: JPL engineers used SeaWinds test parts to build much of RapidScat, which also uses a rotating dish antenna.

RapidScat will launch aboard a SpaceX Dragon resupply mission this summer. Flying in the space station's orbit means RapidScat will spend more time observing Earth's tropics than previous scatterometer satellites, which orbited farther north and south.

"RapidScat will be able to, for the first time, map the evolution of winds as the day progresses, which is important for understanding how clouds and precipitation develop, especially in the tropics, which are key regions in Earth's climate system," Rodriguez said. "It will provide a common reference to tie all of these measurements together."

Together with scatterometers managed by India and Europe, RapidScat will maintain the continuous climate record QuikScat began while adding its own unique perspective from orbit.

For more information about ISS-RapidScat, visit:

http://winds.jpl.nasa.gov/missions/RapidScat/

For more information about QuikScat, visit:

http://winds.jpl.nasa.gov/missions/quikscat/

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

For more information about NASA's Earth science activities in 2014, visit:

http://www.nasa.gov/earthrightnow

Alan Buis

818-354-0474

Jet Propulsion Laboratory, Pasadena, Calif.

Alan.Buis@jpl.nasa.gov


Written by Rosalie Murphy

JPL Earth Science and Technology Directorate


#2014-194
Posted by Nelio Inacio at 7:39 AM 0 comments

Titan's Building Blocks Might Pre-date Saturn

Titan's Building Blocks Might Pre-date Saturn:

Titan
New research on the nitrogen in Titan's atmosphere indicates that the moon's raw materials might have been locked up in ices that condensed before Saturn began its formation.
Image Credit: NASA/JPL-Caltech/Space Science Institute
› Full image and caption


June 23, 2014

A combined NASA and European Space Agency (ESA)-funded study has found firm evidence that nitrogen in the atmosphere of Saturn's moon Titan originated in conditions similar to the cold birthplace of the most ancient comets from the Oort cloud. The finding rules out the possibility that Titan's building blocks formed within the warm disk of material thought to have surrounded the infant planet Saturn during its formation.

The main implication of this new research is that Titan's building blocks formed early in the solar system's history, in the cold disk of gas and dust that formed the sun. This was also the birthplace of many comets, which retain a primitive, or largely unchanged, composition today.

The research, led by Kathleen Mandt of Southwest Research Institute in San Antonio, and including an international team of researchers, was published this week in the Astrophysical Journal Letters.

Nitrogen is the main ingredient in the atmosphere of Earth, as well as on Titan. The planet-sized moon of Saturn is frequently compared to an early version of Earth, locked in a deep freeze.

The paper suggests that information about Titan's original building blocks is still present in the icy moon's atmosphere, allowing researchers to test different ideas about how the moon might have formed. Mandt and colleagues demonstrate that a particular chemical hint as to the origin of Titan's nitrogen should be essentially the same today as when this moon formed, up to 4.6 billion years ago. That hint is the ratio of one isotope, or form, of nitrogen, called nitrogen-14, to another isotope, called nitrogen-15.

The team finds that our solar system is not old enough for this nitrogen isotope ratio to have changed significantly. This is contrary to what scientists commonly have assumed.

"When we looked closely at how this ratio could evolve with time, we found that it was impossible for it to change significantly. Titan's atmosphere contains so much nitrogen that no process can significantly modify this tracer even given more than four billion years of solar system history," Mandt said.

The small amount of change in this isotope ratio over long time periods makes it possible for researchers to compare Titan's original building blocks to other solar system objects in search of connections between them.

As planetary scientists investigate the mystery of how the solar system formed, isotope ratios are one of the most valuable types of clues they are able to collect. In planetary atmospheres and surface materials, the specific amount of one form of an element, like nitrogen, relative to another form of that same element can be a powerful diagnostic tool because it is closely tied to the conditions under which materials form.

The study also has implications for Earth. It supports the emerging view that ammonia ice from comets is not likely to be the primary source of Earth's nitrogen. In the past, researchers assumed a connection between comets, Titan and Earth, and supposed the nitrogen isotope ratio in Titan's original atmosphere was the same as that ratio is on Earth today. Measurements of the nitrogen isotope ratio at Titan by several instruments of the NASA and ESA Cassini-Huygens mission showed that this is not the case -- meaning this ratio is different on Titan and Earth -- while measurements of the ratio in comets have borne out their connection to Titan. This means the sources of Earth's and Titan's nitrogen must have been different.

Other researchers previously had shown that Earth's nitrogen isotope ratio likely has not changed significantly since our planet formed.

"Some have suggested that meteorites brought nitrogen to Earth, or that nitrogen was captured directly from the disk of gas that formed the sun. This is an interesting puzzle for future investigations," Mandt said.

Mandt and colleagues are eager to see whether their findings are supported by data from ESA's Rosetta mission, when it studies comet 67P/ Churyumov-Gerasimenko beginning later this year. If their analysis is correct, the comet should have a lower ratio of two isotopes -- in this case of hydrogen in methane ice -- than the ratio on Titan. In essence, they believe this chemical ratio on Titan is more similar to Oort cloud comets than comets born in the Kuiper Belt, which begins near the orbit of Neptune (67P/ Churyumov-Gerasimenko is a Kuiper Belt comet).

"This exciting result is a key example of Cassini science informing our knowledge of the history of solar system and how the Earth formed," said Scott Edgington, Cassini deputy project scientist at NASA's Jet Propulsion Laboratory, Pasadena, California.

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, Pasadena, manages the mission for NASA's Science Mission Directorate in Washington.

Rosetta is an ESA mission with contributions from its member states and NASA. JPL manages the U.S. contribution of the Rosetta mission for NASA's Science Mission Directorate in Washington.

More information about Cassini is available at the following sites:

http://www.nasa.gov/cassini

http://saturn.jpl.nasa.gov

Preston Dyches/Whitney Clavin

NASA's Jet Propulsion Laboratory, Pasadena, Calif.

818-354-7013/818-354-4673

preston.dyches@jpl.nasa.gov/whitney.clavin@jpl.nasa.gov


2014-200
Posted by Nelio Inacio at 7:39 AM 0 comments
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