In November, the chill and snow of a Northern Hemisphere winter is on the horizon. Snow covers the far north and high elevations, as shown in the map of percent snow cover in November 2009. White areas show where snow covers the ground completely, while blue points to areas with partial snow cover. At the peak of the northern winter, more than 40 percent of the Earth’s land will be covered in snow.

In addition to being an important, life-sustaining source of water, the snow also reflects sunlight, limiting the amount of heat the Earth absorbs from the sun.

January festivities include a panel of past center directors on Jan. 22, 2010 and a gala dinner on Jan. 23, 2010. William Ballhaus, a former center director and expert on computational fluid dynamics, and Nichelle Nichols, Lieutenant Uhura from Star Trek, will be guest speakers. Tickets for the dinner are $135 per person and include a three-course dinner and gift bag filled with a commemorative book, DVD and coin.

The 70th anniversary festivities conclude on Jan. 28, 2010 with a 1930s themed celebration, an antique car parade and a one-man play depicting the past innovators at Ames.

For more information on the history of NASA Ames, visit:

"When it comes to building rocky planets like our own, the innermost part of the disk is where the action is," said team member William Danchi at NASA's Goddard Space Flight Center in Greenbelt, Md. Planets forming in a star's inner disk may orbit within its "habitable zone," where conditions could potentially support the development of life.

To achieve the feat, the team used the Keck Interferometer to combine infrared light gathered by both of the observatory's twin 10-meter telescopes, which are separated by 85 meters. The double-barreled approach gives astronomers the effective resolution of a single 85-meter telescope -- several times larger than any now planned.

"Nothing else in the world provides us with the types of measurements the Keck Interferometer does," said Wesley Traub at Caltech's Jet Propulsion Laboratory in Pasadena, Calif. "In effect, it's a zoom lens for the Keck telescopes."

In August 2008, the team -- led by Sam Ragland of Keck Observatory and including astronomers from the California Institute of Technology and the National Optical Astronomical Observatory -- observed a Young Stellar Object (YSO) known as MWC 419. The blue, B-type star has several times the sun's mass and lies about 2,100 light-years away in the constellation Cassiopeia. With an age less than ten million years, MWC 419 ranks as a stellar kindergartener.

The team also employed a new near-infrared camera designed to image wavelengths in the so-called L band from 3.5 to 4.1 micrometers. "This unique infrared capability adds a new dimension to the Keck Interferometer in probing the density and temperature of planet-forming regions around YSO disks. This wavelength region is relatively unexplored," Ragland explained. "Basically, anything we see through this camera is brand new information."

The increased ability to observe fine detail, coupled with the new camera, let the team measure temperatures in the planet-forming disk to within about 50 million miles of the star. "That's about half of Earth's distance from the sun, and well within the orbit of Venus," Danchi said.

For comparison, the planets directly detected around the stars HR 8799, Fomalhaut and GJ 758 orbit between 40 and 100 times farther away.

The team reported temperature measurements of dust at various regions throughout MWC 419's inner disk in the Sept. 20 issue of The Astrophysical Journal. Temperature differences help shed light on the inner disk's detailed structure and may indicate that its dust has different chemical compositions and physical properties, factors that may play a role in the types of planets that form. For example, conditions in our solar system favored the formation of rocky worlds from Mars sunward, whereas gas giants and icy moons assembled farther out.

In turn, the astronomers note, the size of the young star might affect the composition and physical characteristics of its dust disk. The team is continuing to use the Keck Interferometer in a larger program to observe planet-forming disks around sun-like stars.

The Keck Interferometer was developed by the Jet Propulsion Laboratory and the W.M. Keck Observatory. It is managed by the W.M. Keck Observatory, which operates two 10-meter optical/infrared telescopes on the summit of Mauna Kea on the island of Hawaii and is a scientific partnership of the California Institute of Technology, the University of California and NASA. NASA's Exoplanet Science Institute manages time allocation on the telescope for NASA.

Related links:

Keck Telescopes Take Deeper Look at Planetary Nurseries

Twin Keck Telescopes Probe Dual Dust Disks

The Stratospheric Observatory for Infrared Astronomy, a modified 747 jet known as SOFIA, flew for one hour and 19 minutes, which included two minutes with the telescope's doors fully opened. The goal was to allow engineers to understand how air flows in and around the telescope. It was the first time outside air has interacted with the part of the plane that carries the 98-inch infrared telescope.

"Today we opened the telescope cavity door, the first time we have fully exposed the telescope and the largest cavity ever flown while in flight," said Bob Meyer, SOFIA program manager at NASA's Dryden Flight Research Center in Edwards, Calif. "This is a significant step toward certifying NASA's next great observatory for future study of the universe."

Besides these test flights of the airplane, two flights to operate and verify the scientific capabilities of the telescope assembly are planned for spring 2010. Telescope systems such as the vibration isolation system, the inertial stabilization system and the pointing control system will be tested during daytime flights.

These flights will prepare the telescope assembly for the first flight with the telescope operating. That first flight will be the initial opportunity scientists have to use the telescope and begin the process of quantifying its performance to prepare for SOFIA's planned 20-year science program.

SOFIA is a joint venture of NASA and the German Aerospace Center. NASA supplied the aircraft. The telescope was built in Germany.

Dryden manages the SOFIA program. The aircraft is based at NASA's Dryden Aircraft Operations Facility in Palmdale, Calif. NASA's Ames Research Center at Moffett Field, Calif., manages SOFIA's scientific program. The Universities Space Research Association, in Columbia, Md., and the German SOFIA Institute in Stuttgart, Germany, operate SOFIA's scientific program.

To see a picture of SOFIA with the doors to the telescope cavity open, visit:

Leshin previously served as the deputy center director for science and technology at NASA's Goddard Space Flight Center in Greenbelt, Md. She has led the formulation of strategy and the start of new missions since 2008 as Goddard's senior scientist, while providing extensive scientific guidance to lunar architecture and other human spaceflight planning activities.

"I am delighted that Laurie will be joining us as my deputy, and I look forward to working closely with her," said Doug Cooke, associate administrator for NASA's Exploration Systems Mission Directorate. "She has worked with Exploration in the past and has a great track record. I think her experience and skills will be invaluable as we move forward."

Leshin joined NASA in August 2005 as the director of Goddard's Sciences and Exploration Directorate. She came to the agency from Arizona State University, where she was The Dee and John Whiteman Dean Distinguished Professor of Geological Sciences and director of the Center for Meteorite Studies.

Through her research, Leshin sought to decipher the record of water in objects in our solar system. A primary part of the research involved using meteorites from Mars to assess the history of water and the potential for life on the Red Planet. She has been on science teams for several NASA missions, including the Mars Polar Lander and the upcoming Mars Science Laboratory.

Earlier this year, Leshin also led the NASA Innovation and Technology Study Group, a team of 15 that made recommendations on how NASA could increase focus on innovative activities and technologies needed to advance the agency's mission. She earned a bachelor of science degree in chemistry at Arizona State University in 1987 and a doctorate in geochemistry from the California Institute of Technology in 1994.

Prior to coming to NASA, Leshin received the agency's Distinguished Public Service Medal, the highest award for non-NASA personnel. The International Astronomical Union has recognized her contributions to planetary science with the naming of asteroid 4922 Leshin.

The first motion of Endeavour on its rollout to the pad is scheduled for 4 a.m. EST. The 3.4-mile journey is expected to take approximately six hours. Activities include a 7 a.m. photo opportunity of the shuttle's move, followed by an 8:30 a.m. interview availability with Endeavour Flow Director Dana Hutcherson. Reporters must arrive at Kennedy's news center by 6:30 a.m. on Wednesday for transportation to the viewing area.

Live coverage of the move will be shown on NASA Television beginning at 6 a.m. Video highlights will air on the NASA TV Video File.

Foreign journalist media accreditation for rollout is closed. U.S. reporters without permanent Kennedy credentials must apply for accreditation by 4 p.m. Monday, Jan. 4.

Endeavour's astronauts and ground crews will participate in a launch dress rehearsal, known as the Terminal Countdown Demonstration Test, starting Jan. 19. The test provides each shuttle crew with an opportunity to participate in various simulated countdown activities, including equipment familiarization and emergency training. Media events associated with the test and badge pick up information will be announced at a later date.

Journalists must apply for accreditation for the Terminal Countdown Demonstration Test by noon on Friday, Jan. 8.

Reporters requesting accreditation must apply online at:

The six astronauts for Endeavour's STS-130 mission will deliver a third connecting module, the Tranquility node, to the International Space Station. Launch is targeted for 4:39 a.m. Feb. 7.

For NASA TV downlink information, schedules and links to streaming video, visit:

The Stratospheric Observatory for Infrared Astronomy, a modified 747 jet known as SOFIA, flew for one hour and 19 minutes, which included two minutes with the telescope's doors fully opened. The goal was to allow engineers to understand how air flows in and around the telescope. It was the first time outside air has interacted with the part of the plane that carries the 98-inch infrared telescope.

"Today we opened the telescope cavity door, the first time we have fully exposed the telescope and the largest cavity ever flown while in flight," said Bob Meyer, SOFIA program manager at NASA's Dryden Flight Research Center in Edwards, Calif. "This is a significant step toward certifying NASA's next great observatory for future study of the universe."

Besides these test flights of the airplane, two flights to operate and verify the scientific capabilities of the telescope assembly are planned for spring 2010. Telescope systems such as the vibration isolation system, the inertial stabilization system and the pointing control system will be tested during daytime flights.

These flights will prepare the telescope assembly for the first flight with the telescope operating. That first flight will be the initial opportunity scientists have to use the telescope and begin the process of quantifying its performance to prepare for SOFIA's planned 20-year science program.

SOFIA is a joint venture of NASA and the German Aerospace Center. NASA supplied the aircraft. The telescope was built in Germany.

Dryden manages the SOFIA program. The aircraft is based at NASA's Dryden Aircraft Operations Facility in Palmdale, Calif. NASA's Ames Research Center at Moffett Field, Calif., manages SOFIA's scientific program. The Universities Space Research Association, in Columbia, Md., and the German SOFIA Institute in Stuttgart, Germany, operate SOFIA's scientific program.

To see a picture of SOFIA with the doors to the telescope cavity open, visit:

Several years earlier, NASA had acquired a production Lockheed F-104A for use as a research aircraft. On April 13, 1959, Neil Armstrong ferried the supersonic jet from Lockheed's Palmdale, Calif., facility to NASA's Flight Research Center, where it was equipped with special instrumentation and re-designated as a JF-104A. It initially served as a launch platform for parachute test vehicles and experimental sounding rockets. Later, it was used for mission support, pilot proficiency and as a chase plane for other research aircraft. In all, seven NASA pilots flew the airplane 249 times.

On Dec. 20, 1962, NASA research pilot Milton O. Thompson was scheduled to evaluate weather conditions over Mud Lake, Nev., in preparation for the launch of an X-15 rocket plane over that area a few hours later. Weather flights were critical because go/no-go decisions were based on real-time observations made along the planned flight path.

Thompson strapped himself into the JF-104A cockpit, taxied to the runway, took off to the northeast and climbed to cruising altitude. Visibility was clear all along his route. Upon returning to Edwards, Thompson configured the airplane so he could practice simulated X-15 landings on the clay surface of Rogers Dry Lake.

During his first approach he cut throttle, extended speed brakes and began a steep, descending turn toward a runway marked on the lakebed's surface. Decelerating, he lowered the flaps and held 300 knots indicated airspeed as he dove toward the airstrip. The jet lost altitude at a rate of 18,000 feet per minute until he leveled off at 800 feet, lit the afterburner and climbed away.

During his second approach, Thompson noticed the airplane was rolling to the left. He applied full right aileron and rudder but failed to stop the motion. Seeing his airspeed dropping rapidly, he advanced the throttle to full and relit the afterburner. As his speed increased to 300 knots the roll ceased, leaving the airplane in a 90-degree left bank. Thompson increased his speed to 350 knots to gain more control effectiveness and began to troubleshoot the problem.

Guessing that the airplane was experiencing an asymmetric control condition – either flaps or speed brakes – he repeatedly cycled the roll and yaw dampers, flap-selector switch and speed brakes. He verified that both flaps indicated "up" and visually examined the exterior of the aircraft using his rear-view mirrors. The leading-edge flaps appeared to be up and locked but he couldn't see the trailing-edge flaps. Thompson knew he was in serious trouble and wasn't sure he could land safely. It slowly dawned on him that he might have to eject.

In a last-ditch effort, Thompson radioed NASA-1 – the Flight Operations office – and urgently asked for fellow research pilot Joe Walker, who was suiting up for his X-15 mission.

"Trouble?" Walker asked.

"Right, Joe," said Thompson, "I'm running out of right aileron."

After a brief discussion, Walker decided one of the flaps might be locked in the down position and suggested that Thompson cycle the flap lever again. Thompson tried this and immediately knew it was a mistake, as the airplane started to roll rapidly. He soon realized the situation was hopeless.

"She's going, Joe!" he called.

After four complete rolls, Thompson ejected while inverted. He felt a terrible pain in his neck as the seat's rocket motor blasted him free of the airplane. His body was whipped by air blast, and he began to tumble wildly. After rocket burnout, he separated from the seat but soon realized he was still holding onto the ejection handle. His parachute opened promptly as soon as he released his grip.

Floating gently down from 18,000 feet, Thompson saw the airplane plummet nose-first into the desert and explode on the Edwards bombing range. He was breathing rapidly and felt lightheaded and slightly breathless. After several failed attempts to activate his bailout oxygen bottle, he unfastened his mask and breathed the thin, but fresh, air. He landed softly, gathered up his parachute, and walked to a nearby road.

At NASA-1, the mood was grim. Thompson hadn't had time to inform anyone that he was ejecting and nobody saw his parachute. Their faces bearing shock and tears, NASA employees stared at the column of thick, black smoke rising in the distance.

NASA Flight Operations chief Joe Vensel hopped in a car and sped across the lakebed toward the crash site, expecting the worst. To his surprise, he found Thompson waiting calmly by the roadside, apparently unharmed.

An investigation revealed that the accident had most likely been the result of an electrical malfunction in the left trailing-edge flap. The investigating board, headed by Donald R. Bellman, gave Thompson high marks for his actions.

"Throughout the emergency," the board's report read, "the pilot showed superior skill and judgment, which contributed materially to his own safety and to the understanding of the causes of the aircraft loss."

At a very early age, children learn how to classify objects according to their shape. Now, new research suggests studying the shape of the aftermath of supernovas may allow astronomers to do the same.

A new study of images from NASA's Chandra X-ray Observatory on supernova remnants -- the debris from exploded stars - shows that the symmetry of the remnants, or lack thereof, reveals how the star exploded. This is an important discovery because it shows that the remnants retain information about how the star exploded even though hundreds or thousands of years have passed.

"It's almost like the supernova remnants have a 'memory' of the original explosion," said Laura Lopez of the University of California at Santa Cruz, who led the study. "This is the first time anyone has systematically compared the shape of these remnants in X-rays in this way."

Astronomers sort supernovas into several categories, or "types," based on properties observed days after the explosion and which reflect very different physical mechanisms that cause stars to explode. But, since observed remnants of supernovas are leftover from explosions that occurred long ago, other methods are needed to accurately classify the original supernovas.

Lopez and colleagues focused on the relatively young supernova remnants that exhibited strong X-ray emission from silicon ejected by the explosion so as to rule out the effects of interstellar matter surrounding the explosion. Their analysis showed that the X-ray images of the ejecta can be used to identify the way the star exploded. The team studied 17 supernova remnants both in the Milky Way galaxy and a neighboring galaxy, the Large Magellanic Cloud.

For each of these remnants there is independent information about the type of supernova involved, based not on the shape of the remnant but, for example, on the elements observed in it. The researchers found that one type of supernova explosion -- the so-called Type Ia -- left behind relatively symmetric, circular remnants. This type of supernova is thought to be caused by a thermonuclear explosion of a white dwarf, and is often used by astronomers as "standard candles" for measuring cosmic distances.

On the other hand, the remnants tied to the "core-collapse" supernova explosions were distinctly more asymmetric. This type of supernova occurs when a very massive, young star collapses onto itself and then explodes.

"If we can link supernova remnants with the type of explosion," said co-author Enrico Ramirez-Ruiz, also of University of California, Santa Cruz, "then we can use that information in theoretical models to really help us nail down the details of how the supernovas went off."

Models of core-collapse supernovas must include a way to reproduce the asymmetries measured in this work and models of Type Ia supernovas must produce the symmetric, circular remnants that have been observed.

Out of the 17 supernova remnants sampled, ten were classified as the core-collapse variety, while the remaining seven of them were classified as Type Ia. One of these, a remnant known as SNR 0548-70.4, was a bit of an "oddball." This one was considered a Type Ia based on its chemical abundances, but Lopez finds it has the asymmetry of a core-collapse remnant.

"We do have one mysterious object, but we think that is probably a Type Ia with an unusual orientation to our line of sight," said Lopez. "But we'll definitely be looking at that one again."

While the supernova remnants in the Lopez sample were taken from the Milky Way and its close neighbor, it is possible this technique could be extended to remnants at even greater distances. For example, large, bright supernova remnants in the galaxy M33 could be included in future studies to determine the types of supernova that generated them.

The paper describing these results appeared in the November 20 issue of The Astrophysical Journal Letters. NASA's Marshall Space Flight Center in Huntsville, Ala., manages the Chandra program for NASA's Science Mission Directorate in Washington. The Smithsonian Astrophysical Observatory controls Chandra's science and flight operations from Cambridge, Mass.

More information, including images and other multimedia, can be found at:

http://chandra.harvard.edu

It was taken on 24 October using two of Herschel’s instruments: the Photodetector Array Camera and Spectrometer (PACS) and the Spectral and Photometric Imaging Receiver (SPIRE). The two bright regions are areas where large newborn stars are causing hydrogen gas to shine.

The new OSHI website that goes live today will become the library of Herschel’s best images. Stunning views of the infrared sky will be made available as the mission progresses. Each will be captioned in a way to make them accessible to media representatives, educators and the public.

Embedded within the dusty filaments in the Aquila image are 700 condensations of dust and gas that will eventually become stars. Astronomers estimate that about 100 are protostars, celestial objects in the final stages of formation. Each one just needs to ignite nuclear fusion in its core to become a true star. The other 600 objects are insufficiently developed to be considered protostars, but these too will eventually become another generation of stars.

This cloud is part of Gould’s Belt, a giant ring of stars that circles the night sky – the Solar System just happens to lie near the centre of the belt. The first to notice this unexpected alignment, in the mid-19th century, was England’s John Herschel, the son of William, after whom ESA’s Herschel telescope is named. But it was Boston-born Benjamin Gould who brought the ring to wider attention in 1874.

Gould’s Belt supplies bright stars to many constellations such as Orion, Scorpius and Crux, and conveniently provides nearby star-forming locations for astronomers to study. Observing these stellar nurseries is a key programme for Herschel, which aims to uncover the demographics of star formation and its origin, or in other words, the quantities of stars that can form and the range of masses that such newborn stars can possess. Apart from this region of Aquila, Herschel will target 14 other star-forming regions as part of the Gould’s Belt Key Programme.

Notes for editors:

The scientific rights of these Herschel observations are owned by the consortium of the Gould Belt Key Programme, led by P. André (CEA Saclay). A total of 15 nearby star-forming regions such as Aquila will be studied as part of this Programme.

"Our jaws dropped when we saw the movies for the first time," said space scientist Larry Lyons of the University of California-Los Angeles (UCLA), a member of the team that made the discovery. "These outbursts are telling us something very fundamental about the nature of auroras."

The collisions occur on such a vast scale that isolated observers on Earth -- with limited fields of view -- had never noticed them before. It took a network of sensitive cameras spread across thousands of miles to get the big picture.

NASA and the Canadian Space Agency created such a network for THEMIS, short for "Time History of Events and Macroscale Interactions during Substorms." THEMIS consists of five identical probes launched in 2006 to solve a long-standing mystery: Why do auroras occasionally erupt in an explosion of light called a substorm?

Twenty all-sky imagers (ASIs) were deployed across the Alaskan and Canadian Arctic to photograph auroras from below while the spacecraft sampled charged particles and electromagnetic fields from above. Together, the on-ground cameras and spacecraft would see the action from both sides and be able to piece together cause and effect-or so researchers hoped. It seems to have worked.

The breakthrough came earlier this year when UCLA researcher Toshi Nishimura assembled continent-wide movies from the individual ASI cameras. "It can be a little tricky," Nishimura said. "Each camera has its own local weather and lighting conditions, and the auroras are different distances from each camera. I've got to account for these factors for six or more cameras simultaneously to make a coherent, large-scale movie."

The first movie he showed Lyons was a pair of auroras crashing together in Dec. 2007. "It was like nothing I had seen before," Lyons recalled. "Over the next several days, we surveyed more events. Our excitement mounted as we became convinced that the collisions were happening over and over."

The explosions of light, they believe, are a sign of something dramatic happening in the space around Earth-specifically, in Earth's "plasma tail." Millions of kilometers long and pointed away from the sun, the plasma tail is made of charged particles captured mainly from the solar wind. Sometimes called the "plasma sheet," the tail is held together by Earth's magnetic field.

The same magnetic field that holds the tail together also connects it to Earth's polar regions. Because of this connection, watching the dance of Northern Lights can reveal much about what's happening in the plasma tail.

THEMIS project scientist Dave Sibeck of NASA's Goddard Space Flight Center, Greenbelt, Md. said, "By putting together data from ground-based cameras, ground-based radar, and the THEMIS spacecraft, we now have a nearly complete picture of what causes explosive auroral substorms."

Lyons and Nishimura have identified a common sequence of events. It begins with a broad curtain of slow-moving auroras and a smaller knot of fast-moving auroras, initially far apart. The slow curtain quietly hangs in place, almost immobile, when the speedy knot rushes in from the north. The auroras collide and an eruption of light ensues.

How does this sequence connect to events in the plasma tail? Lyons believes the fast-moving knot is associated with a stream of relatively lightweight plasma jetting through the tail. The stream gets started in the outer regions of the plasma tail and moves rapidly inward toward Earth. The fast knot of auroras moves in synch with this stream.

Meanwhile, the broad curtain of auroras is connected to the stationary inner boundary of the plasma tail and fueled by plasma instabilities there. When the lightweight stream reaches the inner boundary of the plasma tail, there is an eruption of plasma waves and instabilities. This collision of plasma is mirrored by a collision of auroras over the poles.

National Science Foundation-funded radars located in Poker Flat, Alaska, and Sondrestrom, Greenland, confirm this basic picture. They have detected echoes of material rushing through Earth's upper atmosphere just before the auroras collide and erupt. The five THEMIS spacecraft also agree. Last winter, they were able to fly through the plasma tail and confirm the existence of lightweight flows rushing toward Earth.

Scientists from NASA's Langley Research Center and Hampton University in Hampton, Va., and the National Center for Atmospheric Research in Boulder, Colo., presented these results at the fall meeting of the American Geophysical Union in San Francisco from Dec. 14 to 18.

Earth's thermosphere and mesosphere have been the least explored regions of the atmosphere. The NASA Thermosphere-Ionosphere-Mesosphere Energetics and Dynamics (TIMED) mission was developed to explore the Earth’s atmosphere above 60 km altitude and was launched in December 2001. One of four instruments on the TIMED mission, the Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) instrument, was specifically designed to measure the energy budget of the mesosphere and lower thermosphere. The SABER dataset now covers eight years of data and has already provided some basic insight into the heat budget of the thermosphere on a variety of timescales.

The extent of current solar minimum conditions has created a unique situation for recent SABER datasets, explains Stan Solomon, acting director of the High Altitude Observatory, National Center for Atmospheric Research in Boulder, Colo. The end of solar cycle 23 has offered an opportunity to study the radiative cooling in the thermosphere under exceptionally quiescent conditions.

"The Sun is in a very unusual period," said Marty Mlynczak, SABER associate principal investigator and senior research scientist at NASA Langley. "The Earth’s thermosphere is responding remarkably — up to an order of magnitude decrease in infrared emission/radiative cooling by some molecules."

The TIMED measurements show a decrease in the amount of ultraviolet radiation emitted by the Sun. In addition, the amount of infrared radiation emitted from the upper atmosphere by nitric oxide molecules has decreased by nearly a factor of 10 since early 2002. These observations imply that the upper atmosphere has cooled substantially since then. The research team expects the atmosphere to heat up again as solar activity starts to pick up in the next year.

While this warming has no implications for climate change in the troposphere, a fundamental prediction of climate change theory is that the upper atmosphere will cool in response to increasing carbon dioxide. As the atmosphere cools the density will increase, which ultimately may impact satellite operations through increased drag over time.

The SABER dataset is the first global, long-term, and continuous record of the Nitric oxide (NO) and Carbon dioxide (CO2) emissions from the thermosphere.

"We suggest that the dataset of radiative cooling of the thermosphere by NO and CO2 constitutes a first climate data record for the thermosphere," says Mlynczak.

The TIMED data provide a climate record for validation of upper atmosphere climate models, which is an essential step in making accurate predictions of climate change in the high atmosphere. SABER provides the first long-term measurements of natural variability in key terms of the upper atmosphere climate.

"A fundamental prediction of climate change theory is that upper atmosphere will cool in response to greenhouse gases in the troposphere," says Mlynczak. "Scientists need to validate that theory. This climate record of the upper atmosphere is our first chance to have the other side of the equation."

James Russell III, SABER principal investigator and co-director of the Center for Atmospheric Sciences at Hampton University in Hampton, Va., agrees adding, "The atmosphere is a coupled system. If you pick up one end of the stick, you automatically pick up the other – they're intrinsically linked. To be as accurate as possible, scientists have to understand global change throughout the atmosphere."

As the TIMED mission continues, these data derived from SABER will become important in assessing long term atmospheric changes due to the increase of carbon dioxide in the atmosphere.

TIMED is the first mission in the Solar Terrestrial Probes Program within the Heliophysics Division in NASA's Science Mission Directorate in Washington.

Related Links:
› TIMED Mission
› SABER Instrument

Researchers report that in 2004, the state’s natural ecosystems absorbed as much carbon dioxide from the atmosphere as fossil fuel carbons emitted into the atmosphere. They also discovered that during periods of above normal rainfall, ecosystems trapped significant amounts of carbon dioxide from the atmosphere in forests and soils. For these reasons, researchers suggest the ecosystems should be more extensively protected and conserved, and their emissions be monitored as closely as fossil fuel sources of GHG emissions. The results, based largely on a computer model called the NASA-Carnegie Ames Stanford Approach (CASA), will be presented this morning at the 2009 American Geophysical Union Fall meeting in San Francisco.

"One way to facilitate emissions reductions is by using regional and national carbon budgets," explained Christopher Potter, senior research scientist at NASA Ames Research Center, Moffett Field, Calif., and author of this study. "California’s growing population and demand for all forms of energy make it essential to maintain an accurate and complete accounting of the state’s greenhouse emissions inventory," Potter added.

California’s population is more than 10 percent of the total population in the United States, and produces 13 percent of the U.S. gross domestic product, according to 2000 U.S. Census Bureau data. Because of its large population, the state also contributes significantly to global GHG emissions. If California was a country, it would rank among the top 20 national GHG emitters worldwide.

The carbon budget of a region is determined by the amounts of carbon dioxide and methane gases absorbed or released by “green” vegetative ground cover, as observed by NASA satellites. These fluctuations are important to quantify, because they originate from both natural and anthropogenic processes.

In California, the main sources of carbon dioxide emissions are energy consumption in commercial, residential, industrial, and transportation sectors, production of cement and lime, and waste treatment. The main sources of methane emission are derived from landfills and agricultural (principally livestock-based) systems.

Scientists believe that California’s carbon budget is of special interest because the state may represent a U.S. national carbon budget; both have diversified lands, similar consumption of natural resources, and urban lifestyles. Other similarities include a mix of fossil fuel emissions, alternative energy sources, and ecosystem sinks.

Each year, California is required by law to compile a new carbon emission inventory, which is conducted by the California Energy Commission and California’s Air Resources Board. To refine the state’s emission inventory, NASA was asked to provide NASA satellite imaging data and carbon models. To locate the largest ecosystem sources and carbon sinks in California, scientists used the Moderate Resolution Imaging Spectroradiometer (MODIS) aboard the NASA Terra satellite. The vegetation “greenness” data from the MODIS sensor was directly downloaded into the CASA ecosystem simulation model. Scientists used the data to estimate monthly variations in the accumulated biomass of wood and other plant materials, such as the accumulated dead leaf biomass transferred into soil carbon pools. Inventory data from the California Energy Commission also was used to model the carbon dioxide emissions from fossil fuel combustion and greenhouse gas emissions from agricultural lands throughout the state.

This project was funded by NASA as part of a long-term research program dedicated to understanding how human-induced and natural changes affect our global environment.

The study considered not only everyday radiation emanating from space, but also the additional energy unleashed during a solar storm, which can be profound. NASA scientists say not including geomagnetic effects on solar radiation in modeling radiation exposure could underestimate the dosage by 30 to 300 percent.

Researchers looked at passengers and crew on typical flights from Chicago to Beijing, Chicago to Stockholm and London to New York, during what is known as the Halloween 2003 Storm. These flights were chosen because of their long flight paths near the North Pole, where the Earth’s natural protection from radiation is weakest. Earth’s magnetic field approaches zero above the poles. The Halloween 2003 event was chosen because it was both a large and a complex storm, making it a good test for the model.

The study found that aircrew and passengers during the Chicago to Beijing flight, for example, would have been exposed to about 12 percent of the annual radiation limit recommended by the International Committee on Radiological Protection. But these exposures were greater than on typical flights at lower latitudes, and confirmed the concerns about commercial flights at high latitudes.

“The upshot is that these international flights were right there at that boundary where many of these events can take place, where radiation exposure can be much higher,” said Chris Mertens, senior research scientist at NASA’s Langley Research Center, who is leading the research effort. Mertens will present his latest results at the American Geophysical Union fall meeting in San Francisco on Dec. 16.

Piecing together the radiation exposure on these typical flights is the first step toward developing a real-time system that researchers hope will become a standard component of commercial airline cockpits. Radiation exposure could one day be taken into account in the same way weather conditions are considered before deciding to fly or deciding what exact route to fly and at what altitude.

Flying above and beyond Earth’s natural protection

The number of international flights that skirt the north pole are increasing. Airlines save massive amounts of fuel on flights such as Chicago-to-Shanghai by simply flying “over the top” – it is a far shorter route than following the latitude lines. But while saving fuel, these flight paths take planes and their passengers to the thinner layers of Earth’s magnetosphere, which shields potentially harmful solar and cosmic radiation.

On a typical day, the Sun is quiet and “background radiation,” the cumulative effect of radiation from cosmic sources reaching Earth, is the only other source. But when the Sun is not quiet, violent storms on the star’s surface eject powerful bursts of radiation to the Earth. It is these events that have never been truly accounted for in studies of how much radiation pilots and airline passengers are exposed to.

Pilots Await Results

While the flights studied appear to have not put passengers in danger of exceeding the safe radiation limit in an individual flight, concerns remain, Mertens said. Many workers whose jobs expose them to consistent radiation sources log that exposure to keep a record over one’s career. People who work on commercial airline flights are technically listed as “radiation workers” by the federal government – a classification that includes nuclear plant workers and X-ray technicians. But unlike some others in that category, flight crews do not quantify the radiation they are exposed to.

Mike Holland, an American Airlines captain and vice chairman for radiation and environmental issues with the Allied Pilots Association, said he is following Mertens’ research with interest. The pilots association has written a formal letter in support of the research. Holland cited studies that show pilots face a four-times greater risk of melanoma than the general population. But because pilots and flight crews do not wear radiation-measuring badges like other radiation workers, the only estimates about their career-long exposure come from models.

Up until now, most of those models only attempted to capture the amount of cosmic background radiation that reaches airliners in flight. Holland said he believes including solar radiation, especially during solar storms, is important. He looks forward to having answers for the pilots who contact him with questions about radiation and cancer risk.

“When I talk to epidemiologists, they have two questions for me: What is your exposure? And what is your health for 20 to 30 years after you retire?” Holland said. The second question he and other pilots can answer, in time. But as of now, they can’t measure their exposure.

“We’re excited that Chris is doing this,” Holland said, “and we hope it can answer the epidemiologists first question, which is, ‘What is your exposure?’”

Related Links:

> NAIRAS at Space Environment Technologies
> Advanced Satellite Aviation Weather Products (ASAP)
> NASA's Applied Sciences Program

With its 14 spectral bands from the visible to the thermal infrared wavelength region and its high spatial resolution of 50 to 300 feet, ASTER images Earth to map and monitor the changing surface of our planet. ASTER is one of five Earth-observing instruments launched Dec. 18, 1999, on NASA's Terra satellite.

The broad spectral coverage and high spectral resolution of ASTER provides scientists in numerous disciplines with critical information for surface mapping and monitoring of dynamic conditions and temporal change.