Showing posts with label nasa images. Show all posts
Showing posts with label nasa images. Show all posts

Tuesday, July 22, 2014

Last Command Sent to Planck Space Telescope

Last Command Sent to Planck Space Telescope:

An artist's concept of Planck
The oldest light in the universe, called the cosmic microwave background, as observed by the Planck space telescope is shown in the oval sky map. An artist's concept of Planck is next to the map. Image credit: ESA and the Planck Collaboration - D. Ducros

› Full image and caption

October 23, 2013

The Planck space telescope has been turned off after spending nearly 4.5 years soaking up the relic radiation from the Big Bang and studying the evolution of stars and galaxies throughout the history of the universe.


Planck is a European Space Agency (ESA) mission with significant contributions from NASA.


Mission controllers at ESA's operations center in Darmstadt, Germany sent the final command to the Planck satellite today, marking the end of operations for what some like to call a "time machine."


"We are only part way through the analysis of the data and have already learned a huge amount about the universe from the Milky Way galaxy, to the observable edge, and beyond to the first tiny fraction of a second after the Big Bang," said U.S. Planck Project Scientist Charles Lawrence of NASA's Jet Propulsion Laboratory, Pasadena, Calif.


Launched in 2009, Planck was designed to tease out the faintest relic radiation from the Big Bang, called the cosmic microwave background. This radiation preserves a picture of the universe as it was about 380,000 years after its birth, and provides details of the initial conditions that led to the universe we live in today.


Results from the mission presented by scientists in March 2013 provided revised values for the relative proportions of the ingredients of the universe, namely normal matter that makes up stars and galaxies; dark matter, which has so far only been detected indirectly by its gravitational influence; and dark energy, a mysterious force thought to be responsible for accelerating the expansion of the universe. The NASA news release about these results is at http://www.jpl.nasa.gov/news/news.php?release=2013-109 .


JPL built critical components of Planck's science instruments, including bolometers for the mission's high-frequency instrument; a 20-Kelvin (minus-424-degree-Fahrenheit) cryocooler for both the low- and high-frequency instruments; and amplifier technology for the low-frequency instrument.


But cooling instruments to these extreme temperatures cannot be maintained forever and, indeed, the High Frequency Instrument exhausted its liquid helium coolant in January 2012, just as expected.


The Low Frequency Instrument meanwhile continued to operate at somewhat higher temperatures using the remaining two coolers, and it observed the sky until Oct. 3. After conducting post-science activities, it was manually switched off Oct. 19.


"Planck is a model for international cooperation in space. Both Europe and the U.S. contributed enabling new technologies, giving Planck unprecedented scientific capability," said Ulf Israelsson, the U.S. Planck Project Manager at JPL.


Read the full ESA news release at: http://spaceinimages.esa.int/Images/2013/03/Planck_and_the_cosmic_microwave_background .


Planck is a European Space Agency mission, with significant participation from NASA. NASA's Planck Project Office is based at JPL. JPL contributed mission-enabling technology for both of Planck's science instruments. European, Canadian and U.S. Planck scientists work together to analyze the Planck data. More information is online at http://www.nasa.gov/planck, http://www.esa.int/planck and http://planck.caltech.edu .

Whitney Clavin 818-354-4673?

Jet Propulsion Laboratory, Pasadena, Calif.?

whitney.clavin@jpl.nasa.gov


2013-303
Posted by Nelio Inacio at 6:35 PM 0 comments
Labels: , ,

NASA's Great Observatories Begin Deepest-Ever Probe of the Universe

NASA's Great Observatories Begin Deepest-Ever Probe of the Universe:

Galaxy clusters
These are NASA Hubble Space Telescope natural-color images of four target galaxy clusters that are part of an ambitious new observing program called The Frontier Fields.
› Full image and caption

October 24, 2013

PASADENA, Calif. -- NASA's Hubble, Spitzer and Chandra space telescopes are teaming up to look deeper into the universe than ever before. With a boost from natural "zoom lenses" found in space, they should be able to uncover galaxies that are as much as 100 times fainter than what these three great observatories typically can see.


In an ambitious collaborative program called The Frontier Fields, astronomers will make observations during the next three years peering at six massive clusters of galaxies, exploiting a natural phenomenon known as gravitational lensing, to learn not only what is inside the clusters but also what is beyond them. The clusters are among the most massive assemblages of matter known, and their gravitational fields can be used to brighten and magnify more distant galaxies so they can be observed.


"The Frontier Fields program is exactly what NASA's Great Observatories were designed to do; working together to unravel the mysteries of the universe" said John Grunsfeld, associate administrator for NASA's Science Mission Directorate in Washington. "Each observatory collects images using different wavelengths of light with the result that we get a much deeper understanding of the underlying physics of these celestial objects."


The first object they will view is Abell 2744, commonly known as Pandora's Cluster. The giant galaxy cluster appears to be the result of a simultaneous pile-up of at least four separate, smaller galaxy clusters that took place over a span of 350 million years.


Astronomers anticipate these observations will reveal populations of galaxies that existed when the universe was only a few hundred million years old, but have not been seen before.


"The idea is to use nature's natural telescopes in combination with the great observatories to look much deeper than before and find the most distant and faint galaxies we can possibly see," said Jennifer Lotz, a principal investigator with the Space Telescope Science Institute in Baltimore, Md.


Data from the Hubble and Spitzer space telescopes will be combined to measure the galaxies' distances and masses more accurately than either observatory could measure alone, demonstrating their synergy for such studies.


"We want to understand when and how the first stars and galaxies formed in the universe, and each great observatory gives us a different piece of the puzzle," said Peter Capak, the Spitzer principal investigator for the Frontier Fields program at NASA's Spitzer Science Center at the California Institute of Technology, Pasadena. "Hubble tells you which galaxies to look at and how many stars are being born in those systems. Spitzer tells you how old the galaxy is and how many stars have formed."


The Chandra X-ray Observatory also will peer deep into the star fields. It will image the clusters at X-ray wavelengths to help determine their mass and measure their gravitational lensing power, and identify background galaxies hosting supermassive black holes.


High-resolution Hubble data from Frontier Fields will be used to trace the distribution of dark matter within the six massive foreground clusters. Accounting for the bulk of the universe's mass, dark matter is the underlying invisible scaffolding attached to galaxies.


Hubble and Spitzer have studied other deep fields with great success. The Frontier Fields researchers anticipate a challenge because the distortion and magnification caused by the gravitational lensing phenomenon will make it difficult for them to understand the true properties of the background galaxies.


For images and more information about The Frontier Fields, visit: http://hubblesite.org/news/2013/44 .


NASA's Jet Propulsion Laboratory, Pasadena, Calif., manages the Spitzer Space Telescope mission for NASA's Science Mission Directorate, Washington. Science operations are conducted at the Spitzer Science Center at Caltech. Spacecraft operations are based at Lockheed Martin Space Systems Company, Littleton, 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

Ray Villard 410-338-4514

Space Telescope Science Institute, Baltimore, Md.

villard@stsci.edu

J.D. Harrington 202-358-5241

Headquarters, Washington

j.d.harrington@nasa.gov


2013-306
Posted by Nelio Inacio at 6:34 PM 0 comments
Labels: , ,

Carbon Worlds May be Waterless, Finds NASA Study

Carbon Worlds May be Waterless, Finds NASA Study:

This artist's concept illustrates the fate of two different planets: the one on the left is similar to Earth, made up largely of silicate-based rocks with oceans coating its surface
This artist's concept illustrates the fate of two different planets: the one on the left is similar to Earth, made up largely of silicate-based rocks with oceans coating its surface. The one on the right is rich in carbon -- and dry. Chances are low that life as we know it, which requires liquid water, would thrive under such barren conditions. Image credit: NASA/JPL-Caltech
› Full image and caption

October 25, 2013

Planets rich in carbon, including so-called diamond planets, may lack oceans, according to NASA-funded theoretical research.


Our sun is a carbon-poor star, and as result, our planet Earth is made up largely of silicates, not carbon. Stars with much more carbon than the sun, on the other hand, are predicted to make planets chock full of carbon, and perhaps even layers of diamond.


By modeling the ingredients in these carbon-based planetary systems, the scientists determined they lack icy water reservoirs thought to supply planets with oceans.


"The building blocks that went into making our oceans are the icy asteroids and comets," said Torrence Johnson of NASA's Jet Propulsion Laboratory in Pasadena, Calif, who presented the results Oct. 7 at the American Astronomical Society Division of Planetary Sciences meeting in Denver. Johnson, a team member of several NASA planetary missions, including Galileo, Voyager and Cassini, has spent decades studying the planets in our own solar system.


"If we keep track of these building blocks, we find that planets around carbon-rich stars come up dry," he said.


Johnson and his colleagues say the extra carbon in developing star systems would snag the oxygen, preventing it from forming water.


"It's ironic that if carbon, the main element of life, becomes too abundant, it will steal away the oxygen that would have made water, the solvent essential to life as we know it," said Jonathan Lunine of Cornell University, Ithaca, N.Y., a collaborator on the research.


One of the big questions in the study of planets beyond our solar system, called exoplanets, is whether or not they are habitable. Researchers identify such planets by first looking for those that are situated within the "habitable zone" around their parent stars, which is where temperatures are warm enough for water to pool on the surface. NASA's Kepler mission has found several planets within this zone, and researchers continue to scrutinize the Kepler data for candidates as small as Earth.


But even if a planet is found in this so-called "Goldilocks" zone, where oceans could, in theory, abound, is there actually enough water available to wet the surface? Johnson and his team addressed this question with planetary models based on measurements of our sun's carbon-to-oxygen ratio. Our sun, like other stars, inherited a soup of elements from the Big Bang and from previous generations of stars, including hydrogen, helium, nitrogen, silicon, carbon and oxygen.


"Our universe has its own top 10 list of elements," said Johnson, referring to the 10 most abundant elements in our universe.


These models accurately predict how much water was locked up in the form of ice early in the history of our solar system, billions of years ago, before making its way to Earth. Comets and/or the parent bodies of asteroids are thought to have been the main water suppliers, though researchers still debate their roles. Either way, the objects are said to have begun their journey from far beyond Earth, past a boundary called the "snow line," before impacting Earth and depositing water deep in the planet and on its surface.


When the researchers applied the planetary models to the carbon-rich stars, the water disappeared. "There's no snow beyond the snow line," said Johnson.


"All rocky planets aren't created equal," said Lunine. "So-called diamond planets the size of Earth, if they exist, will look totally alien to us: lifeless, ocean-less desert worlds."


The computer model results supporting these conclusions were published in the Astrophysical Journal last year (http://arxiv.org/abs/1208.3289). The implications for habitability in these systems were the focus of the Division of Planetary Sciences meeting.


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

Whitney Clavin 818-354-4673

Jet Propulsion Laboratory, Pasadena, Calif.

whitney.clavin@jpl.nasa.gov


2013-308
Posted by Nelio Inacio at 6:33 PM 0 comments
Labels: , ,

Ghostly Specter Haunts the 'Coldest Place in the Universe'

Ghostly Specter Haunts the 'Coldest Place in the Universe':

The Boomerang nebula, called the
The Boomerang nebula, called the "coldest place in the universe," reveals its true shape to the Atacama Large Millimeter/submillimeter Array (ALMA) telescope. Image credit: NRAO/AUI/NSF/NASA/STScI/JPL-Caltech

› Full image and caption

October 25, 2013

At a cosmologically crisp one degree Kelvin (minus 458 degrees Fahrenheit), the Boomerang nebula is the coldest known object in the universe -- colder, in fact, than the faint afterglow of the Big Bang, the explosive event that created the cosmos.


Astronomers using the Atacama Large Millimeter/submillimeter Array (ALMA) telescope in Chile have taken a new look at this object to learn more about its frigid properties and to determine its true shape, which has an eerily ghost-like appearance.


"This ultra-cold object is extremely intriguing and we're learning much more about its true nature with ALMA," said Raghvendra Sahai, a researcher and principal scientist at NASA's Jet Propulsion Laboratory in Pasadena, Calif., and lead author of a paper published in the Astrophysical Journal. "What seemed like a double lobe, or boomerang shape, from Earth-based optical telescopes, is actually a much broader structure that is expanding rapidly into space."


As originally observed with ground-based telescopes, this nebula appeared lopsided, which is how it got its name. Later observations with NASA's Hubble Space Telescope revealed a bow-tie-like structure. The new ALMA data, however, reveal that the Hubble image tells only part of the story, and the twin lobes seen in that image may actually be a trick of light as seen at visible wavelengths.


The researchers discovered a dense lane of millimeter-sized dust grains surrounding the star, which explains why its outer cloud has an hourglass shape in visible light. These minute dust grains have created a mask that shades a portion of the central star and allows its light to leak out only in narrow but opposite directions into the cloud, giving it an hourglass appearance.


"This is important for the understanding of how stars die and become planetary nebulas," said Sahai. "Using ALMA, we were quite literally, and figuratively, able to shed new light on the death throes of a sun-like star."


The Boomerang nebula, located about 5,000 light-years away in the constellation Centaurus, is a relatively young example of an object known as a planetary nebula. Planetary nebulas, contrary to their name, are actually the end-of-life phases of stars like our sun that have sloughed off their outer layers. What remains at their centers are white dwarf stars, which emit intense ultraviolet radiation that causes the gas in the nebulae to glow and emit light in brilliant colors.


Read the full ALMA release online at https://public.nrao.edu/news/pressreleases/alma-reveals-coldest-place-in-the-universe .


Additional authors on this paper include Wouter Vlemmings, Chalmers University of Technology, Onsala, Sweden; Patrick Huggins, New York University, New York; Lars-Ake Nyman, Joint ALMA Observatory, Santiago de Chile; and Yiannis Gonidakis, CSIRO, Australia Telescope National Facility.


ALMA, an international astronomy facility, is a partnership of Europe, North America and East Asia in cooperation with the Republic of Chile. ALMA construction and operations are led on behalf of Europe by European Southern Observatory, on behalf of North America by the National Radio Astronomy Observatory (NRAO), and on behalf of East Asia by the National Astronomical Observatory of Japan (NAOJ). The Joint ALMA Observatory (JAO) provides the unified leadership and management of the construction, commissioning and operation of ALMA.


The National Radio Astronomy Observatory is a facility of the National Science Foundation, operated under cooperative agreement by Associated Universities, Inc.


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

Whitney Clavin 818-354-4673

Jet Propulsion Laboratory, Pasadena, Calif.

whitney.clavin@jpl.nasa.gov


2013-310
Posted by Nelio Inacio at 6:33 PM 0 comments
Labels: , ,

Cassini Swings Above Saturn to Compose a Portrait

Cassini Swings Above Saturn to Compose a Portrait:

A swing high above Saturn by NASA's Cassini spacecraft revealed this stately view of the golden-hued planet and its main rings
A swing high above Saturn by NASA's Cassini spacecraft revealed this stately view of the golden-hued planet and its main rings. The view is in natural color, as human eyes would have seen it. Image credit: NASA/JPL-Caltech/SSI/Cornell

› Full image and caption

October 25, 2013

It's a view as good as gold. A loop high above Saturn by NASA's Cassini spacecraft revealed this stately view of the golden-hued planet and its main rings. The observation and resulting image mosaic were planned as one of three images for Cassini's 2013 Scientist for a Day essay contest. The contest challenges students to study three possible targets and write about which one they think will yield the best science. Today is the last day for U.S. submissions and the Cassini mission has already started working on picking the best essays.


This natural-color view -- seen as human eyes would have seen it - was obtained on Oct. 10, 2013. It shows off the differently colored bands of weather at Saturn. A bright, wavy stream of clouds around 42 degrees north latitude appears to mark some of the turbulent aftermath of a giant storm that reached its violent peak in early 2011. The mysterious six-sided weather pattern known as the hexagon is also visible around Saturn's north pole.


When Cassini arrived in 2004, more of the northern hemisphere sported a bluish hue and it was northern winter. The golden tones dominated the southern hemisphere, where it was southern summer. But as the seasons have turned and northern summer has begun, the colors have begun to change in each hemisphere as well. Golden tones have started to dominate in the northern hemisphere and the bluish color in the north is now confined to a tighter circle around the north pole.


Cassini is currently in a special set of tilted orbits known as "inclined orbits" that allow the spacecraft to swing up over the north pole and below the south pole. Cassini was tilted as much as 62 degrees from the plane of Saturn's equator in April of this year and will continue to work its way back down again till early 2015. Much of Cassini's tour has involved orbits around the equatorial plane, where most of Saturn's rings and moons are located.


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 Cassini-Huygens mission for NASA's Science Mission Directorate in Washington. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging team consists of scientists from the United States, the United Kingdom, France and Germany. The imaging operations center is based at the Space Science Institute in Boulder, Colo.


For more information about Cassini and its mission, visit: http://www.nasa.gov/cassini and http://saturn.jpl.nasa.gov.

Jia-Rui Cook 818-354-0850

Jet Propulsion Laboratory, Pasadena, Calif.

jccook@jpl.nasa.gov

2013-311
Posted by Nelio Inacio at 6:32 PM 0 comments
Labels: , ,

Watching Earth's Winds, On a Shoestring

Watching Earth's Winds, On a Shoestring:

Artist's rendering of NASA's ISS-RapidScat instrument (inset), which will launch to the International Space Station in 2014
Artist's rendering of NASA's ISS-RapidScat instrument (inset), which will launch to the International Space Station in 2014 to measure ocean surface wind speed and direction and help improve weather forecasts, including hurricane monitoring. It will be installed on the end of the station's Columbus laboratory. Credit: NASA/JPL-Caltech/Johnson Space Center.
› Larger image

October 29, 2013

Built with spare parts and without a moment to spare, the International Space Station (ISS)-RapidScat isn't your average NASA Earth science mission.

Short for Rapid Scatterometer, ISS-RapidScat will monitor ocean winds from the vantage point of the space station . It will join a handful of other satellite scatterometer missions that make essential measurements used to support weather and marine forecasting, including the tracking of storms and hurricanes. It will also help improve our understanding of how interactions between Earth's ocean and atmosphere influence our climate.

Scientists study ocean winds for a variety of reasons. Winds over the ocean are an important part of weather systems, and in severe storms such as hurricanes they can inflict major damage. Ocean storms drive coastal surges, which are a significant hazard for populations. At the same time, by driving warm surface ocean water away from the coast, ocean winds cause nutrient-rich deep water to well up, providing a major source of food for coastal fisheries. Changes in ocean wind also help us monitor large-scale changes in Earth's climate, such as El Niño .

Scatterometers work by safely bouncing low-energy microwaves - the same kind used at high energy to warm up food in your kitchen - off the surface of Earth. In this case, the surface is not land, but the ocean. By measuring the strength and direction of the microwave echo, ISS-RapidScat will be able to determine how fast, and in what direction, ocean winds are blowing.

"Microwave energy emitted by a radar instrument is reflected back to the radar more strongly when the surface it illuminates is rougher," explains Ernesto Rodríguez, principal investigator for ISS-RapidScat at NASA's Jet Propulsion Laboratory, Pasadena, Calif. "When wind blows over water, it causes waves to develop along the direction of wind. The stronger the wind, the larger the waves."

ISS-RapidScat continues a legacy of measuring ocean winds from space that began in 1978 with the launch of NASA's SeaSat satellite. Most recently, NASA's QuikScat scatterometer, which launched in 1999, gave us a dynamic picture of the world's ocean winds.

But when QuikScat lost its ability to produce ocean wind measurements in 2009, science suffered from the loss of the data. In the summer of 2012, an opportunity arose to fly a scatterometer instrument on the space station. ISS-RapidScat was the result .

Most scatterometer-carrying satellites fly in what's called a sun-synchronous orbit around Earth. In other words, they cross Earth's equator at the same local time every orbit. The space station, however, will carry the ISS-RapidScat in a non-sun-synchronous orbit. This means the instrument will see different parts of the planet at different times of day, making measurements in the same spot within less than an hour before or after another instrument makes its own observations. These all-hour measurements will allow ISS-RapidScat to pick up the effects of the sun on ocean winds as the day progresses. In addition, the space station's coverage over the tropics means that ISS-RapidScat will offer extra tracking of storms that may develop into hurricanes or other tropical cyclones.

Anywhere the wind blows

"We'll be able to see how wind speed changes with the time of day," said Rodríguez. "ISS-RapidScat will link together all previous and current scatterometer missions, providing us with a more complete picture of how ocean winds change. Combined with data from the European ASCAT scatterometer mission, we'll be able to observe 90 percent of Earth's surface at least once a day, and in many places, several times a day."

ISS-RapidScat's near-global coverage of Earth's ocean -- within the space station's orbit inclination of 51.6 degrees north and south of the equator -- will make it an important tool for scientists who observe and predict Earth's weather. "Frequent observations of the winds over the ocean are used by meteorologists to improve weather and hurricane forecasts and by the operational weather communities to improve numerical weather models," said Rodríguez.

Space-based scatterometer instruments have been built before, but much of what makes ISS-RapidScat unusual is how it came to be. "Space Station Program Manager Michael Suffredini offered us a mounting location on the space station and a free ride on a SpaceX Dragon cargo resupply mission launching in early 2014," explained Howard Eisen, the ISS-RapidScat project manager at JPL. "So we had about 18 months to put together an entire mission."

This accelerated timeline is a blink of an eye at NASA, where the typical project is years or decades in the making.

Free ride

Next, Eisen and his team turned to getting creative and crafty with the mission's hardware. In lieu of using newly-designed instruments, which would be expensive and take too long to develop, ISS-RapidScat reuses leftover hardware originally built to test parts of the QuikScat mission. That process involved dusting off and testing pieces of equipment that hadn't seen the light of day since the 1990s. Fortunately the old hardware seems ship-shape and ready to go. "Even though they were spares, they've done an excellent job so far," said Simon Collins, ISS-RapidScat's instrument manager at JPL. Despite their age, the old parts are more than capable of collecting the ocean wind data that ISS-RapidScat need to be a success.

In addition to old spare parts, some new hardware was needed to interface this instrument to the space station and the Dragon spacecraft. ISS-RapidScat will use off-the-shelf, commercially-available computer hardware instead of the expensive, hardened-against-radiation computer chips that are typically used in space missions. "If there's an error or something because of radiation, all we have to do is reset the computer. It's what we call a managed risk," said Eisen. The radiation environment on the space station is much less severe than that experienced en route to Mars, for example, or in more traditional sun-synchronous orbits.

Science bounty

Cost-saving decisions like this are shaping up to make ISS-RapidScat an exceptional bargain of a space mission. "We're doing things differently, and we're trying to do them quickly and cheaply," said Eisen. Considering that the typical launch alone can cost $200 million, ISS-RapidScat's estimated $26 million price tag seems like a bargain. Last year, NASA estimated the cost of a new, free-flying scatterometer satellite mission at approximately $400 million.

The real challenges of getting ISS-RapidScat into space lie in the details. One of the major headaches of such a hurried schedule has been getting the special connectors that will allow ISS-RapidScat to physically attach to the International Space Station. "They're special robotically-mated connectors that haven't been made in years," Eisen said. "We're having to convince the company that produces these connectors to make us a small run in time for the mission, and it hasn't been easy."

The logistics of operating an instrument on the space station are also tricky. "Typically, spacecraft are designed for the instruments they carry," said Collins. "In this case, it's the other way around." For example, ISS-RapidScat's docking point on the space station faces outward toward space - not down toward Earth and the ocean that the instrument is looking at. The space station's flying angle will also change as new pieces are added to it, in response to changes in the station's drag profile. ISS-RapidScat's mount can compensate for both of these challenges.

Another concern the ISS-RapidScat team confronted early on was that one of the space station's docking ports lies squarely within the field of view of the scatterometer. "Bombarding astronauts and visiting supply vehicles with microwave radiation from the instruments was out of the question, and turning the instrument off when there were things docked there would take away too much science," explained Collins. The project's engineers instead devised a plan where the instrument avoids irradiating docking vessels, but continues to scan across the vast majority of its viewing range.

Rodríguez is confident that the reward for overcoming such difficulties will be a bounty of vital science information. "Because it uses much of the same hardware QuikScat did, ISS-RapidScat will allow us to continue the observations of ocean winds already started," said Rodriguez. "Extending this data record will help us observe and understand weather patterns and improve our preparedness for tropical cyclones."

Joshua Rodriguez

Jet Propulsion Laboratory, Pasadena Calif.

Media contact:

Alan Buis 818-354-0474

Jet Propulsion Laboratory, Pasadena Calif.

Alan.buis@jpl.nasa.gov

2013-313
Posted by Nelio Inacio at 6:32 PM 0 comments
Labels: , ,

A Ghostly Trio from NASA's Spitzer Space Telescope

A Ghostly Trio from NASA's Spitzer Space Telescope:

This trio of ghostly images from NASA's Spitzer Space Telescope shows the disembodied remains of dying stars called planetary nebulas
This trio of ghostly images from NASA's Spitzer Space Telescope shows the disembodied remains of dying stars called planetary nebulas. Image credit: NASA/JPL-Caltech/Harvard-Smithsonian CfA

Exposed Cranium Nebula (left) | Ghost of Jupiter Nebula (middle) |
Little Dumbbell Nebula (right)

› Full image and caption

October 28, 2013

In the spirit of Halloween, scientists are releasing a trio of stellar ghosts caught in infrared light by NASA's Spitzer Space Telescope. All three spooky structures, called planetary nebulas, are in fact material ejected from dying stars. As death beckoned, the stars' wispy bits and pieces were blown into outer space.


"Some might call the images haunting," said Joseph Hora of the Harvard-Smithsonian Center for Astrophysics, Cambridge, Mass., principal investigator of the Spitzer observing program. "We look to the pictures for a sense of the history of the stars' mass loss, and to learn how they evolved over time."


All stars about the mass of our sun will die similarly ethereal deaths. As sun-like stars grow old, billions of years after their inception, they run out of fuel in their cores and puff up into red, giant stars, aptly named "red giants." The stars eventually cast off their outer layers, which expand away from the star. When ultraviolet light from the core of a dying star energizes the ejected layers, the billowy material glows, bringing their beautiful shapes to light.


These objects in their final death throes, the planetary nebulas, were named erroneously after their resemblance to planets by William Herschel in 1785. They come in an array of shapes, as illustrated by the three highlighted here in infrared images from Spitzer. The ghostly material will linger for only a few thousand years before ultimately fading into the dark night.


Exposed Cranium Nebula


The brain-like orb called PMR 1 has been nicknamed the "Exposed Cranium" nebula by Spitzer scientists. This planetary nebula, located roughly 5,000 light-years away in the Vela constellation, is host to a hot, massive dying star that is rapidly disintegrating, losing its mass. The nebula's insides, which appear mushy and red in this view, are made up primarily of ionized gas, while the outer green shell is cooler, consisting of glowing hydrogen molecules.


Ghost of Jupiter Nebula


The Ghost of Jupiter, also known as NGC 3242, is located roughly 1,400 light-years away in the constellation Hydra. Spitzer's infrared view shows off the cooler outer halo of the dying star, colored here in red. Also evident are concentric rings around the object, the result of material being tossed out periodically during the star's fitful death.


Little Dumbbell Nebula


This planetary nebula, known as NGC 650, or the Little Dumbbell, is about 2,500 light-years from Earth in the Perseus constellation. Unlike the other spherical nebulas, it has a bipolar or butterfly shape due to a "waist," or disk, of thick material, running from lower left to upper right. Fast winds blow material away from the star, above and below this dusty disk. The ghoulish green and red clouds are from glowing hydrogen molecules. The green area is hotter than the red.


NASA's Jet Propulsion Laboratory, Pasadena, Calif., manages the Spitzer Space Telescope mission for NASA's Science Mission Directorate, Washington. Science operations are conducted at the Spitzer Science Center at the California Institute of Technology in Pasadena. Spacecraft operations are based at Lockheed Martin Space Systems Company, Littleton, Colorado. Data are archived at the Infrared Science Archive housed at the Infrared Processing and Analysis Center at Caltech. Caltech manages JPL for NASA. For more information about Spitzer, visit http://spitzer.caltech.edu and http://www.nasa.gov/spitzer .

Whitney Clavin 818-354-4673

Jet Propulsion Laboratory, Pasadena, Calif.

whitney.clavin@jpl.nasa.gov


2013-312
Posted by Nelio Inacio at 6:31 PM 0 comments
Labels: , ,

Scientists Discover the First Earth-size Rocky Planet

Scientists Discover the First Earth-size Rocky Planet:

This illustration compares Earth with the newly confirmed scorched world of Kepler-78b.
This illustration compares Earth with the newly confirmed scorched world of Kepler-78b. Kepler-78b is about 20 percent larger than Earth and is 70% more massive. Kepler-78b whizzes around its host star every 8.5 hours, making it a blazing inferno. Credit: David A. Aguilar (CfA)
› Larger image

October 30, 2013

Astronomers have discovered the first Earth-size planet outside the solar system that has a rocky composition like that of Earth. Kepler-78b whizzes around its host star every 8.5 hours, making it a blazing inferno and not suitable for life as we know it. The results are published in two papers in the journal Nature.


"The news arrived in grand style with the message: 'Kepler-10b has a baby brother,'" said Natalie Batalha, Kepler mission scientist at NASA's Ames Research Center in Moffett Field, Calif. Batalha led the team that discovered Kepler-10b, a larger but also rocky planet identified by NASA's Kepler spacecraft.


"The message expresses the joy of knowing that Kepler's family of exoplanets is growing," Batalha reflects. "It also speaks of progress. The Doppler teams are attaining higher precision, measuring masses of smaller planets at each turn. This bodes well for the broader goal of one day finding evidence of life beyond Earth."


Kepler-78b was discovered using data from NASA's Kepler space telescope, which for four years simultaneously and continuously monitored more than 150,000 stars, looking for telltale dips in their brightness caused by crossing, or transiting, planets.


Two independent research teams then used ground-based telescopes to confirm and characterize Kepler-78b. To determine the planet's mass, the teams employed the radial velocity method to measure how much the gravitational tug of an orbiting planet causes its star to wobble. Kepler, on the other hand, determines the size or radius of a planet by the amount of starlight blocked when it passes in front of its host star.


A handful of planets the size or mass of Earth have been discovered. Kepler-78b is the first to have both a measured mass and size. With both quantities known, scientists can calculate a density and determine what the planet is made of.


Kepler-78b is 1.2 times the size of Earth and 1.7 times more massive, resulting in a density that is the same as Earth's. This suggests that Kepler-78b is also made primarily of rock and iron. Its star is slightly smaller and less massive than the sun and is located about 400 light-years from Earth in the constellation Cygnus.


One team, led by Andrew Howard from the University of Hawaii in Honolulu, made follow-up observations using the W. M. Keck Observatory on Mauna Kea in Hawaii. More information on their research can be found at: http://www.ifa.hawaii.edu/info/press-releases/Kepler-78b/ .


The other team led by Francesco Pepe from the University of Geneva, Switzerland, did their ground-based work at the Roque de los Muchachos Observatory on La Palma in the Canary Islands. More information on their research can be found at http://www.cfa.harvard.edu/news/2013-25 .


This result will be one of many discussed next week at the second Kepler science conference Nov. 4 to 8 at Ames. More than 400 astrophysicists from Australia, China, Europe, Latin America and the U.S. will convene to present their latest results using publicly accessible data from Kepler. More information about the conference is at:
http://nexsci.caltech.edu/conferences/KeplerII/index.shtml .


Ames is responsible for Kepler's ground system development, mission operations and science data analysis. JPL managed Kepler mission development. Ball Aerospace & Technologies Corp. in Boulder, Colo., 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 was funded by the agency's Science Mission Directorate. For more information about the Kepler mission, visit: http://www.nasa.gov/kepler and http://www.kepler.nasa.gov .

Whitney Clavin 818-354-4673

Jet Propulsion Laboratory, Pasadena, Calif.

whitney.clavin@jpl.nasa.gov


Michele Johnson 650-604-6982

Ames Research Center, Moffett Field, Calif.

michele.johnson@nasa.gov


2013-316
Posted by Nelio Inacio at 6:30 PM 0 comments
Labels: , ,

NASA Hosts Earth Science Social Media Event

NASA Hosts Earth Science Social Media Event:

This view of Earth comes from NASA's Moderate Resolution Imaging Spectroradiometer aboard the Terra satellite.
This view of Earth comes from NASA's Moderate Resolution Imaging Spectroradiometer aboard the Terra satellite.
› Larger image

October 29, 2013

One-hundred people from 22 U.S. states and some foreign countries will attend a two-day NASA Social on Nov. 4 and 5 at the agency's Jet Propulsion Laboratory in Pasadena, Calif.


The attendees, who follow NASA and JPL on Twitter, Facebook, Google+ and other social networks, will tour JPL, participate in interactive events and hear from scientists and engineers about current and upcoming space- and Earth-observing missions. Attendees will share their experiences with their followers through the various social media platforms.


The Nov. 4 events will highlight NASA's role in studying Earth and its climate and will preview three Earth-observing missions JPL is preparing for launch in 2014: the Soil Moisture Active Passive (SMAP) spacecraft, which will measure soil moisture from space; ISS-RapidScat, which will measure ocean winds from the International Space Station; and the Orbiting Carbon Observatory-2 (OCO-2), which will study atmospheric carbon dioxide from space.


These presentations will air on NASA Television on Nov. 4 starting at 10 a.m. PST (1 p.m. EST) at http://www.nasa.gov/ntv and http://www.ustream.tv/nasajpl2 .


To join and track the conversation online during the NASA Social, follow the hashtag #NASASocial .


NASA Social attendees were selected from more than 475 people who registered online. Participants represent Canada, Croatia, Indonesia, Norway, Peru, the United States and the United Kingdom. Attendees from the U.S. come from 22 states: Alabama, Alaska, Arizona, Arkansas, California, Colorado, Georgia, Illinois, Maine, Maryland, Massachusetts, Nebraska, Nevada, New Jersey, New York, North Carolina, Oregon, Texas, Utah, Virginia, Washington and Wisconsin.


More information about connecting and collaborating with NASA is at: http://www.nasa.gov/connect .


More information about SMAP is online at: http://smap.jpl.nasa.gov/ . More information about ISS-RapidScat is at: http://www.nasa.gov/mission_pages/station/research/experiments/ISSRapidScat.html and http://winds.jpl.nasa.gov/missions/RapidScat/ .


More information about OCO-2 is at: http://oco.jpl.nasa.gov/ .


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

Courtney O'Connor 818-354-2274

Jet Propulsion Laboratory, Pasadena, Calif.

oconnor@jpl.nasa.gov

John Yembrick / Jason Townsend 202-358-1584 / 202-358-0359

NASA Headquarters, Washington

john.yembrick@nasa.gov / jason.c.townsend@nasa.gov

2013-315b
Posted by Nelio Inacio at 6:29 PM 0 comments
Labels: , ,

'Witch Head' Brews Baby Stars

'Witch Head' Brews Baby Stars:

An infrared portrait of the Witch Head nebula from NASA's Wide-field Infrared Survey Explorer
An infrared portrait of the Witch Head nebula from NASA's Wide-field Infrared Survey Explorer, or WISE, shows billowy clouds where new stars are brewing. Image credit: NASA/JPL-Caltech
› Larger image

October 30, 2013

A witch appears to be screaming out into space in this new image from NASA's Wide-Field Infrared Survey Explorer, or WISE. The infrared portrait shows the Witch Head nebula, named after its resemblance to the profile of a wicked witch. Astronomers say the billowy clouds of the nebula, where baby stars are brewing, are being lit up by massive stars. Dust in the cloud is being hit with starlight, causing it to glow with infrared light, which was picked up by WISE's detectors.


The Witch Head nebula is estimated to be hundreds of light-years away in the Orion constellation, just off the famous hunter's knee.


WISE was recently "awakened" to hunt for asteroids in a program called NEOWISE. The reactivation came after the spacecraft was put into hibernation in 2011, when it completed two full scans of the sky, as planned.

Whitney Clavin 818-354-4673

Jet Propulsion Laboratory, Pasadena, Calif.

whitney.clavin@jpl.nasa.gov


2013-317
Posted by Nelio Inacio at 6:28 PM 0 comments
Labels: , ,

Galaxy Growth Examined Like Rings of a Tree

Galaxy Growth Examined Like Rings of a Tree:

Galaxies Grow from Inside Out
New evidence from NASA's Wide-field Infrared Survey Explorer (WISE) and Galaxy Evolution Explorer (GALEX) missions provide support for the "inside-out" theory of galaxy evolution, which holds that star formation starts at the core of the galaxy and spreads outward. Image credit: NASA/JPL-Caltech
› Full image and caption

October 31, 2013

-- Like tree rings, inner and outer portions of a galaxy's disk are a historical record

-- Two NASA missions find evidence that star formation bursts started in galaxy centers and spread outward

-- Unexplained ultraviolet light might come from a late phase in the lives of older stars


---------------------------------------------------------------------------------------------------------------------------------


Watching a tree grow might be more frustrating than waiting for a pot to boil, but luckily for biologists, there are tree rings. Beginning at a tree trunk's dense core and moving out to the soft bark, the passage of time is marked by concentric rings, revealing chapters of the tree's history.


Galaxies outlive trees by billions of years, making their growth impossible to see. But like biologists, astronomers can read the rings in a galaxy's disk to unravel its past. Using data from NASA's Wide-field Infrared Survey Explorer (WISE) and Galaxy Evolution Explorer (GALEX), scientists have acquired more evidence for the "inside-out" theory of galaxy growth, showing that bursts of star formation in central regions were followed one to two billion years later by star birth in the outer fringes.


"Initially, a rapid star-forming period formed the mass at the center of these galaxies, followed later by a star-forming phase in the outer regions. Eventually, the galaxies stop making stars and become quiescent," said Sara Petty of Virginia Tech, Blacksburg, Va., lead author of a paper appearing in the October 2013 issue of the Astronomical Journal. "This later star-forming phase could have been caused by minor mergers with gas-rich neighbors, which provide the fuel for new stars."


The discovery may also solve a mystery of elderly galaxies. The galaxies in the study, known as "red and dead" for their red color and lack of new star births, have a surprising amount of ultraviolet light emanating from the outer regions. Often, ultraviolet light is generated by hot, young stars, but these galaxies were considered too old to host such a young population.


The solution to the puzzle is likely hot, old stars. Petty and colleagues used a new multi-wavelength approach to show that the unexplained ultraviolet light appears to be coming from a late phase in the lives of older stars, when they blow off their outer layers and heat up.


GALEX and WISE turned out to be the ideal duo for the study. GALEX was sensitive to the ultraviolet light, whereas WISE sees the infrared light coming from older stars. GALEX is no longer operating, but WISE was recently reactivated to hunt asteroids, a project called NEOWISE (see http://www.jpl.nasa.gov/news/news.php?release=2013-257 ). Both telescopes have large fields of view, allowing them to easily capture images of entire galaxies.


"The synergy between GALEX and WISE produces a very sensitive measurement of where the hot, older stars reside in these red-and-dead galaxies," said Don Neill, co-author of the paper from the California Institute of Technology, Pasadena. "This allows us to map the progress of star formation within each galaxy."


Ned Wright of UCLA, a co-author of the study and the principal investigator of WISE before it was reactivated, compares the multi-wavelength range of the two telescopes to musical notes, "WISE itself covers the equivalent of a three-octave range, while WISE and GALEX together cover a seven-octave range."


The technical paper for this study is online at http://arxiv.org/abs/1307.6282 .


NASA's Jet Propulsion Laboratory, Pasadena, Calif., manages and operates the recently activated NEOWISE mission for NASA's Science Mission Directorate. The WISE mission was selected competitively under NASA's Explorers Program managed by the agency's Goddard Space Flight Center in Greenbelt, Md. The science instrument was built by the Space Dynamics Laboratory in Logan, Utah. The spacecraft was built by Ball Aerospace & Technologies Corp. in Boulder, Colo. Science operations and data processing take place at the Infrared Processing and Analysis Center at Caltech. Caltech manages JPL for NASA. More information is online at http://www.nasa.gov/wise and http://wise.astro.ucla.edu and http://www.jpl.nasa.gov/wise .


Caltech led the Galaxy Evolution Explorer mission and was responsible for science operations and data analysis. JPL managed the mission and built the science instrument. The mission was developed under NASA's Explorers Program managed by the Goddard Space Flight Center, Greenbelt, Md. Researchers sponsored by Yonsei University in South Korea and the Centre National d'Etudes Spatiales (CNES) in France collaborated on this mission. Graphics and additional information about the Galaxy Evolution Explorer are online at http://www.nasa.gov/galex and http://www.galex.caltech.edu .


Whitney Clavin 818-354-4673

Jet Propulsion Laboratory, Pasadena, Calif.

whitney.clavin@jpl.nasa.gov


2013-318
Posted by Nelio Inacio at 6:28 PM 0 comments
Labels: , ,

Black Holes Don't Make a Big Splash

Black Holes Don't Make a Big Splash:

Black Holes Make Waves in Ocean of Space-Time
Merging black holes ripple space and time in this artist's concept. Pulsar-timing arrays -- networks of the pulsing cores of dead stars -- are one strategy for detecting these ripples, or gravitational waves, thought to be generated when two supermassive black holes merge into one.

Image credit: Swinburne Astronomy Productions
› Larger image

November 06, 2013

Throughout our universe, tucked inside galaxies far, far away, giant black holes are pairing up and merging. As the massive bodies dance around each other in close embraces, they send out gravitational waves that ripple space and time themselves, even as the waves pass right through our planet Earth.


Scientists know these waves, predicted by Albert Einstein's theory of relativity, exist but have yet to directly detect one. In the race to catch the waves, one strategy -- called pulsar-timing arrays -- has reached a milestone not through detecting any gravitational waves, but in revealing new information about the frequency and strength of black hole mergers.


"We expect that many gravitational waves are passing through us all the time, and now we have a better idea of the extent of this background activity," said Sarah Burke-Spolaor, co-author of a new Science paper published Oct. 18, which describes research she contributed to while based at NASA's Jet Propulsion Laboratory in Pasadena, Calif. Burke-Spolaor is now at the California Institute of Technology in Pasadena.


Gravitational waves, if detected, would reveal more information about black holes as well as one of the four fundamental forces of nature: gravity.


The team's inability to detect any gravitational waves in the recent search actually has its own benefits, because it reveals new information about supermassive black hole mergers -- their frequency, distance from Earth and masses. One theory of black hole growth to hit the theorists' cutting room floors had stated that mergers alone are responsible for black holes gaining mass.


The results come from the Commonwealth Scientific and Industrial Research Organization's (CSIRO) Parkes radio telescope in eastern Australia. The study was jointly led by Ryan Shannon of CSIRO, and Vikram Ravi, of the University of Melbourne and CSIRO.


Pulsar-timing arrays are designed to catch the subtle gravitational waves using telescopes on the ground, and spinning stars called pulsars. Pulsars are the burnt-out cores of exploded stars that send out beams of radio waves like lighthouse beacons. The timing of the pulsars' rotation is so precise that researchers say they are akin to atomic clocks.


When gravitational waves pass through an array of multiple pulsars, 20 in the case of the new study, they set the pulsars bobbing like buoys. Researchers recording the radio waves from the pulsars can then piece together the background hum of waves.


"The gravitational waves cause the space between Earth and pulsars to stretch and squeeze," said Burke-Spolaor.


The new study used the Parkes Pulsar Timing Array, which got its start in the 1990s. According to the research team, the array, at its current sensitivity, will be able to detect a gravitational wave within 10 years.


Researchers at JPL are currently developing a similar precision pulsar-timing capability for NASA's Deep Space Network, a system of large dish antennas located around Earth that tracks and communicates with deep-space spacecraft. During gaps in the network's tracking schedules, the antennas can be used to precisely measure the timing of pulsars' radio waves. Because the Deep Space Network's antennas are distributed around the globe, they can see pulsars across the whole sky, which improves sensitivity to gravitational waves.


"Right now, the focus in the pulsar-timing array communities is to develop more sensitive technologies and to establish long-term monitoring programs of a large ensemble of the pulsars," said Walid Majid, the principal investigator of the Deep Space Network pulsar-timing program at JPL. "All the strategies for detecting gravitational waves, including LIGO [Laser Interferometer Gravitational-Wave Observatory], are complementary, since each technique is sensitive to detection of gravitational waves at very different frequencies. While some might characterize this as a race, in the end, the goal is to detect gravitational waves, which will usher in the beginning of gravitational wave astronomy. That is the real exciting part of this whole endeavor."


The ground-based LIGO observatory is based in Louisiana and Washington. It is a joint project of Caltech and the Massachusetts Institute of Technology, Cambridge, Mass., with funding from the National Science Foundation. The European Space Agency is developing the space-based LISA Pathfinder (Laser Interferometer Space Antenna), a proof-of-concept mission for a future space observatory to detect gravitational waves. LIGO, LISA and pulsar-timing arrays would all detect different frequencies of gravitational waves and thus are sensitive to various types of merger events.


A video about the new Parkes findings from Swinburne University of Technology in Melbourne, Australia, is online at: http://astronomy.swin.edu.au/production/blackhole/ .


Caltech manages JPL for NASA.

Whitney Clavin 818-354-4673

Jet Propulsion Laboratory, Pasadena, Calif.

whitney.clavin@jpl.nasa.gov


2013-320
Posted by Nelio Inacio at 6:27 PM 0 comments
Labels: , ,

NASA's GRAIL Mission Puts a New Face on the Moon

NASA's GRAIL Mission Puts a New Face on the Moon:

Using a precision formation-flying technique, the twin GRAIL spacecraft will map the moon's gravity field, as depicted in this artist's rendering.
Using a precision formation-flying technique, the twin GRAIL spacecraft mapped the moon's gravity field, as depicted in this artist's rendering. Image credit: NASA/JPL-Caltech
› Full image and caption

November 07, 2013

Scientists using data from the lunar-orbiting twins of NASA's Gravity Recovery and Interior Laboratory (GRAIL) mission are gaining new insight into how the face of the moon received its rugged good looks. A report on the asymmetric distribution of lunar impact basins is published in this week's edition of the journal Science.


"Since time immemorial, humanity has looked up and wondered what made the man in the moon," said Maria Zuber, GRAIL principal investigator from the Massachusetts Institute of Technology in Cambridge. "We know the dark splotches are large, lava-filled, impact basins that were created by asteroid impacts about four billion years ago. GRAIL data indicate that both the near side and the far side of the moon were bombarded by similarly large impactors, but they reacted to them much differently."


Understanding lunar impact basins has been hampered by the simple fact that there is a lack of consensus on their size. Most of the largest impact basins on the near side of the moon (the moon's face) have been filled with lava flows, which hide important clues about the shape of the land that could be used for determining their dimensions. The GRAIL mission measured the internal structure of the moon in unprecedented detail for nine months in 2012. With the data, GRAIL scientists have redefined the sizes of massive impact basins on the moon.


Maps of crustal thickness generated by GRAIL revealed more large impact basins on the near-side hemisphere of the moon than on the far side. How could this be if both hemispheres were, as widely believed, on the receiving end of the same number of impacts?


Scientists have long known that the temperatures of the near-side hemisphere of the moon were higher than those on the far side: the abundances of the heat producing elements uranium and thorium are higher on the near side than the far side, and as a consequence, the vast majority of volcanic eruptions occurred on the moon's near-side hemisphere.


"Impact simulations indicate that impacts into a hot, thin crust representative of the early moon's near-side hemisphere would have produced basins with as much as twice the diameter as similar impacts into cooler crust, which is indicative of early conditions on the moon's far-side hemisphere," notes lead author Katarina Miljkovic of the Institut de Physique du Globe de Paris.


The new GRAIL research is also helping redefine the concept of the late heavy bombardment, a proposed spike in the rate of crater creation by impacts about 4 billion years ago. The late heavy bombardment is based largely on the ages of large near-side impact basins that are either within, or adjacent to the dark, lava-filled basins, or lunar maria, named Oceanus Procellarum and Mare Imbrium. However, the special composition of the material on and below the surface of the near side implies that the temperatures beneath this region were not representative of the moon as a whole at the time of the late heavy bombardment. The difference in the temperature profiles would have caused scientists to overestimate the magnitude of the basin-forming impact bombardment. Work by GRAIL scientists supports the hypothesis that the size distribution of impact basins on the far-side hemisphere of the moon is a more accurate indicator of the impact history of the inner solar system than those on the near side.


Launched as GRAIL A and GRAIL B in September 2011, the probes, renamed Ebb and Flow by schoolchildren in Montana, operated in a nearly circular orbit near the poles of the moon at an altitude of about 34 miles (55 kilometers) until their mission ended in December 2012. The distance between the twin probes changed slightly as they flew over areas of greater and lesser gravity caused by visible features, such as mountains and craters, and by masses hidden beneath the lunar surface.


JPL, a division of the California Institute of Technology in Pasadena, Calif. managed GRAIL for NASA's Science Mission Directorate in Washington. The mission was part of the Discovery Program managed at NASA's Marshall Space Flight Center in Huntsville, Ala. NASA's Goddard Space Flight Center, in Greenbelt, Md., manages the Lunar Reconnaissance Orbiter. Operations of the spacecraft's laser altimeter, which provided supporting data used in this investigation, is led by the Massachusetts Institute of Technology in Cambridge. Lockheed Martin Space Systems in Denver built GRAIL.


For more information about GRAIL, visit http://www.nasa.gov/grail and http://grail.nasa.gov

DC Agle 818-393-9011

Jet Propulsion Laboratory, Pasadena, Calif.

agle@jpl.nasa.gov


Dwayne Brown 202-358-1726

Headquarters, Washington

dwayne.c.brown@nasa.gov


Sarah McDonnell 617-253-8923

Massachusetts Institute of Technology, Cambridge

s_mcd@mit.edu / cmcall5@mit.edu


2013-322
Posted by Nelio Inacio at 6:23 PM 0 comments
Labels: , ,

Study Finds Climate Link to Atmospheric-River Storms

Study Finds Climate Link to Atmospheric-River Storms:

Animation of the atmospheric-river event.
Animation of the atmospheric-river event. This animation shows an atmospheric river event over Dec. 18-20, 2010. High-altitude winds pull large amounts of water vapor (yellow and orange) from the tropical ocean near Hawaii and carry it straight to California.
Image Credit:
Anthony Wimmers and Chris Velden, University of Wisconsin-CI
› Larger image

November 08, 2013

PASADENA, Calif. - A new NASA-led study of atmospheric-river storms from the Pacific Ocean may help scientists better predict major winter snowfalls that hit West Coast mountains and lead to heavy spring runoff and sometimes flooding.


Atmospheric rivers -- short-lived wind tunnels that carry water vapor from the tropical oceans to mid-latitude land areas -- are prolific producers of rain and snow on California's Sierra Nevada mountains. The finding, published in the journal Water Resources Research, has major implications for water management in the West, where Sierra runoff is used for drinking water, agriculture and hydropower.


The research team studied how two of the most common atmospheric circulation patterns in the Northern Hemisphere interact with atmospheric rivers. They found when those patterns line up in a certain way, they create a virtual freeway that leads the moisture-laden winds straight to the Sierras.


Bin Guan of the Joint Institute for Regional Earth System Science and Engineering, a collaboration between NASA's Jet Propulsion Laboratory in Pasadena, Calif., and UCLA, led a team of scientists from NASA, UCLA and the National Oceanic and Atmospheric Administration (NOAA) on this research.


An atmospheric river is a narrow stream of wind, about a mile (1.6 kilometers) high and sometimes of hurricane strength. Crossing the warm tropical Pacific in a few days, it becomes laden with water vapor. A moderate-sized atmospheric river carries as much water as the Mississippi River dumps into the Gulf of Mexico in an average week. When the river comes ashore and stalls over higher terrain, the water falls as snow or rain.


"Atmospheric rivers are the bridge between climate and West Coast snow," said Guan. "If scientists can predict these atmospheric patterns with reasonable lead times, we'll have a better understanding of water availability and flooding in the region." The benefit of improving flood prediction alone would be significant. A single California atmospheric-river storm in 1999 caused 15 deaths and $570 million in damage.


Guan's team used data from the JPL-developed Atmospheric Infrared Sounder (AIRS) instrument on NASA's Aqua satellite, along with NOAA satellite data and snowpack data from the California Department of Water Resources. They looked at the extremely snowy winter of 2010-2011, when 20 atmospheric rivers made landfall.


The team compared the dates of these events with the phases of the Arctic Oscillation (AO) and the Pacific/North American teleconnection (PNA). These large-scale weather patterns wax and wane, stretching thousands of miles across the atmosphere and shaping the climate of the mid-latitudes, somewhat as the better-known El Niño and La Niña patterns do in the tropical Pacific.


Each pattern affects a different part of the Northern Hemisphere by seesawing between phases of lower-than-average and higher-than-average air pressure over various parts of the globe. For example, the negative phase of the AO is associated with higher pressure in the Arctic and lower pressure in the surrounding lower latitudes. In the positive phase, those highs and lows are reversed.


The phases of each pattern change irregularly and at varying intervals. The researchers charted these phases throughout the winter of 2010-2011. During 15 of the winter's 20 atmospheric river occurrences, both patterns were in the negative phase. The team then looked at the period 1998-2011 and found a similar correspondence: more atmospheric rivers occurred when both patterns were negative.


According to Guan, in the double-negative periods, the high- and low-pressure systems associated with that phase in each pattern mesh to create a lingering atmospheric low-pressure system just northwest of California. That low directs the atmospheric river fire hose straight toward the Sierra Nevadas.


Guan points out that the double-negative phase correlation is rare.


"I looked at 50 years of atmospheric data. Only five months had those phases of the PNA and AO occurring together for more than 15 days of the month," he said.


AIRS was built and is managed by JPL for NASA's Science Mission Directorate in Washington. Aqua is managed by NASA's Goddard Space Flight Center, Greenbelt, Md. JPL is a division of the California Institute of Technology in Pasadena.


For more information on AIRS, visit: http://airs.jpl.nasa.gov .

Alan Buis 818-354-0474

Jet Propulsion Laboratory, Pasadena, Calif.

Alan.Buis@jpl.nasa.gov


Steve Cole 202-358-0918

NASA Headquarters, Washington

Stephen.e.cole@nasa.gov


Written by Carol Rasmussen


2013-323
Posted by Nelio Inacio at 6:23 PM 0 comments
Labels: , , ,

Prolific NASA Mars Orbiter Passes Big Data Milestone

Prolific NASA Mars Orbiter Passes Big Data Milestone:

Artist concept of Mars Reconnaissance Orbiter. Image credit: NASA/JPL
Artist concept of Mars Reconnaissance Orbiter. Image credit: NASA/JPL
› Full image and caption

November 08, 2013

NASA's Mars Reconnaissance Orbiter, which has overhauled understanding of the Red Planet since 2006, has passed 200 terabits in the amount of science data returned. The data returned by the mission alone is more than three times the total data returned via NASA's Deep Space Network for all the other missions managed by NASA's Jet Propulsion Laboratory, Pasadena, Calif., over the past 10 years.


While the 200 terabits number includes all the data this orbiter has relayed to Earth from robots on the surface of Mars, about 99.9 percent of the volume has come from the six science instruments aboard Mars Reconnaissance Orbiter. The 200 terabits are equivalent to the data volume in three nonstop months of high-definition video. The number does not include the engineering data that specialists operating the orbiter from JPL and Lockheed Martin Space Systems, Denver, use for monitoring its health and performance.


The spacecraft pours data Earthward using a dish antenna 10 feet (3 meters) across and a transmitter powered by 215 square feet (20 square meters) of solar cells. Multiple sessions each day with giant dish antennas of the Deep Space Network in California, Spain and Australia enable Earth to receive such a torrent of data from the orbiter.


"The sheer volume is impressive, but of course what's most important is what we are learning about our neighboring planet," said JPL's Rich Zurek, the project scientist for the Mars Reconnaissance Orbiter.


The orbiter's instruments have examined Mars from subsurface to atmosphere in unprecedented detail. One instrument has provided images revealing features as small as a desk in surface areas equivalent to one-third of the United States (1.92 percent of Mars' surface). Another has covered areas equivalent to about 82 percent of Earth's land area (83.6 percent of Mars' surface), with resolution showing features smaller than a tennis court. These cameras have viewed many areas repeatedly, providing three-dimensional information from stereo and revealing several types of landscape changes over time. Other instruments identify surface minerals, probe underground layers, examine cross-sections of the atmosphere and track weather globally.


"The mission has taught us about three very different periods of Mars history," Zurek said.


Its observations of the heavily cratered terrains of Mars, the oldest on the planet, show that different types of ancient watery environments formed water-related minerals. Some of these would have been more favorable for life than others. In more recent times, water appears to have cycled as a gas between polar ice deposits and lower-latitude deposits of ice and snow. Extensive layering in ice or rock probably took hundreds of thousands to millions of years to form. The present climate is also dynamic, with volatile carbon dioxide and, possibly, flows of briny water forming dark streaks that are observed to appear in the warmest seasons and places and fade in colder weather.


"Mars Reconnaissance Orbiter has shown that Mars is still an active planet, with changes such as new craters, avalanches and dust storms," Zurek said. "Mars is a partially frozen world, but not frozen in time."


Each of the 200 trillion bits of science data from the orbiter has followed a complex path, aided by sophisticated software to make it feasible for a small team to handle tens of billions of new bits daily and get the data products to the appropriate scientists.


Data gathered by the orbiter's instruments and relayed from rovers are recorded onto the orbiter's central memory. Each orbit around Mars takes the spacecraft about two hours. For part of each orbit, Mars itself usually blocks the communication path to Earth. When Earth is in view, a Deep Space Network antenna on whichever part of Earth is turned toward Mars at that hour can be listening. Complex preparations coordinate scheduling the use of the network's antennas by all deep-space missions -- 32 of them this month. Mars Reconnaissance Orbiter typically gets several sessions every day.


"The Deep Space Network collects the incoming data into 30-minute chunks," said Mars Reconnaissance Orbiter software engineer Bryan Allen, of JPL. "At that point, it doesn't matter which products are in it -- just a big pile of bits."


The chunks of mixed data from the antenna stations in California, Spain and Australia come to JPL, where software sorts it into specific products, such as an image from a camera, measurements from a scan of the atmosphere, radar readings from the subsurface sounder, or data from a rover. Another process at JPL determines which products to send where -- such as to a mineral-mapping team in Maryland, a camera team in Arizona, a radar team in Italy. On a typical recent day, the system sorted 58 billion bits from Mars Reconnaissance Orbiter into 303 data products.


The Mars Reconnaissance Orbiter mission met all its science goals in a two-year primary science phase ending in 2008. Three extensions, the latest beginning in 2012, have added to the science returns. The longevity of this mission and of NASA's even longer-lived Mars Odyssey orbiter, which has been studying Mars since 2002, have given researchers tools to study seasonal and longer-term changes on the Red Planet.


JPL, a division of the California Institute of Technology, Pasadena, manages the Mars Reconnaissance Orbiter and Mars Odyssey projects for NASA's Science Mission Directorate, Washington. Lockheed Martin Space Systems built both orbiters and collaborates with JPL to operate them. JPL operates the Deep Space Network for NASA's Human Exploration and Operations Mission Directorate, Washington. For more information about the Mars Reconnaissance Orbiter, visit http://www.nasa.gov/mro and http://mars.jpl.nasa.gov/mro/ .

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

Jet Propulsion Laboratory, Pasadena, Calif.

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

2013-324
Posted by Nelio Inacio at 6:22 PM 0 comments
Labels: , ,
Subscribe to: Posts (Atom)