Friday, January 16, 2009

The Human Factor: Understanding the Sources of Rising Carbon Dioxide

Every time we get into our car, turn the key and drive somewhere, we burn gasoline, a fossil fuel derived from crude oil. The burning of the organic materials in fossil fuels produces energy and releases carbon dioxide and other compounds into Earth's atmosphere. Greenhouse gases such as carbon dioxide trap heat in our atmosphere, warming it and disturbing Earth's climate.

Space Station Scientists agree that human activities have been the primary source for the observed rise in atmospheric carbon dioxide since the beginning of the fossil fuel era in the 1860s. Eighty-five percent of all human-produced carbon dioxide emissions come from the burning of fossil fuels like coal, natural gas and oil, including gasoline. The remainder results from the clearing of forests and other land use, as well as some industrial processes such as cement manufacturing. The use of fossil fuels has grown rapidly, especially since the end of World War II and continues to increase exponentially. In fact, more than half of all fossil fuels ever used by humans have been consumed in just the last 20 years.

Human activities add a worldwide average of almost 1.4 metric tons of carbon per person per year to the atmosphere. Before industrialization, the concentration of carbon dioxide in the atmosphere was about 280 parts per million. By 1958, the concentration of carbon dioxide had increased to around 315 parts per million, and by 2007, it had risen to about 383 parts per million. These increases were due almost entirely to human activity.

While we are able to accurately measure the amount of carbon dioxide in the atmosphere, much about the processes that govern its atmospheric concentration remains a mystery. Scientists still do not know precisely where all the carbon dioxide in our atmosphere comes from and where it goes. They want to learn more about the magnitudes and distributions of carbon dioxide's sources and the places it is absorbed (sinks). This knowledge will help improve critical forecasts of atmospheric carbon dioxide increases as fossil fuel use and other human activities continue. Such information is crucial to understanding the impact of human activities on climate and for evaluating options for mitigating or adapting to climate change.

Scientists soon expect to get some answers to these and other compelling carbon questions, thanks to the Orbiting Carbon Observatory, a new Earth-orbiting NASA satellite set to launch in early 2009. The new mission will allow scientists to record, for the first time, detailed daily measurements of carbon dioxide, making more than 100,000 measurements around the world each day. The new data will provide valuable new insights into where this important greenhouse gas is coming from and where it is being stored.

Before humans began emitting significant amounts of carbon dioxide into the atmosphere, the atmospheric uptake and loss of carbon dioxide was approximately in balance. "Carbon dioxide in the atmosphere remained pretty stable during the pre-industrial period," said Gregg Marland of Oak Ridge National Laboratory in Oak Ridge, Tenn. "Carbon dioxide generated by human activity amounts to only about four percent of yearly atmospheric uptake or loss of carbon dioxide, but the result is that the concentration of carbon dioxide in the atmosphere has been growing, on average, by four-tenths of one percent each year for the last 40 years. Though this may not seem like much of an influence, humans have essentially tipped the balance of the global cycling of carbon. Our emissions add significant weight to one side of the balance between carbon being added to the atmosphere and carbon being removed from the atmosphere.

"Plant life and geochemical processes on land and in the ocean 'inhale' large amounts of carbon dioxide through photosynthesis and then 'exhale' most of it back into the atmosphere," Marland continued. "Humans, however, have altered the carbon cycle over the last couple of centuries, through the burning of fossil fuels that enable us to live more productively. Now that humans are acknowledging the environmental effects of our dependence on fossil fuels and other carbon dioxide-emitting activities, our goal is to analyze the sources and sinks of this carbon dioxide and to find better ways to manage it."

Current estimates of human-produced carbon dioxide emissions into the atmosphere are based on inventories and estimates of where fossil fuels are burned and where other carbon dioxide-producing human activities are occurring. However, the availability and precision of this information is not uniform around the world, not even from within developed countries like the United States.

The Orbiting Carbon Observatory's highly sensitive instrument will measure the distribution of carbon dioxide, sampling information around the globe from its space-based orbit. Though the instrument will not directly measure the carbon dioxide emissions from every individual smokestack, tailpipe or forest fire, scientists will incorporate the observatory's global measurements of varying carbon dioxide concentrations into computer-based models. The models will infer where and when the sources are emitting carbon dioxide into the atmosphere.

"The Orbiting Carbon Observatory data differ from that of other missions like the Atmospheric Infrared Sounder instrument on NASA's Aqua satellite by having a relatively small measurement 'footprint,'" said Kevin Gurney, associate director of the Climate Change Research Center at Purdue University in West Lafayette, Ind. "Rather than getting an average amount of carbon dioxide over a large physical area like a state or country, the mission will capture measurements over scales as small as a medium-sized city. This allows it to more accurately distinguish movements of carbon dioxide from natural sources versus from fossil fuel-based activities."

"Essentially, if you visualize a column of air that stretches from Earth's surface to the top of the atmosphere, the Orbiting Carbon Observatory will identify how much of that vertical column is carbon dioxide, with an understanding that most is emitted at the surface," said Marland. "Simply, it will act like a plane observing the smoke from forest fires down below, with the task of assessing where the fires are and how big they are. Compare that aerial capability with sending a lot of people into the forest looking for fires. In this vein, the observatory will use its vantage point from space to peer down and capture a picture of where the sources and sinks of carbon dioxide are, rather than our cobbling data together from multiple sources with less frequency, reliability and detail."

Gurney believes the Orbiting Carbon Observatory will also complement a NASA/U.S. Department of Energy jointly-funded project he is currently leading called Vulcan.

"Vulcan estimates the movement of carbon dioxide through the combustion of fossil fuels at very small scales. Vulcan and the Orbiting Carbon Observatory together will act like partners in closing the carbon budget, with Vulcan estimating movements in the atmosphere from the bottom-up and the Orbiting Carbon Observatory estimating sources from the top-down," he said. "By tackling the problem from both perspectives, we'll stand to achieve an independent, mutually-compatible view of the carbon cycle. And the insight gained by combining these top-down and bottom-up approaches might take on special significance in the near future as our policymakers consider options for regulating carbon dioxide across the entire globe."

For more information on this topic, see: http://www.nasa.gov/oco and http://oco.jpl.nasa.gov .

Discovery At the Launch Pad - Space Shuttle Mission: STS-119

Space shuttle Discovery now sits on Launch Pad 39A at NASA's Kennedy Space Center in Florida -- a major milestone met for the STS-119 mission. The approximate six-hour trip was complete at 12:16 p.m. EST Jan. 14.

The rotating service structure was moved into place around the shuttle to protect it from inclement weather and provide protected access to the orbiter for installation and servicing of payloads at the pad.

At NASA's Johnson Space Center in Houston, the STS-119 crew members are rehearsing spacewalking techniques in the Neutral Buoyancy Laboratory. Later today Commander Lee Archambault and Pilot Tony Antonelli will fly to Edwards Air Force Base in California for landing practice in NASA's Shuttle Training Aircraft.

The Space Shuttle Program's two-day Flight Readiness Review is scheduled for Jan. 12-22. On Feb. 3 NASA senior managers will hold an Executive Review to set the official launch date for STS-119's 14-day mission to the International Space Station.

Commander Lee Archambault will lead a crew of seven, along with Pilot Tony Antonelli, and Mission Specialists Joseph Acaba, John Phillips, Steve Swanson, Richard Arnold and Japan Aerospace Exploration Agency astronaut Koichi Wakata.

The astronauts will fly to Kennedy for a full-dress rehearsal called the Terminal Countdown Demonstration Test, or TCDT, scheduled for Jan. 19-21. They will have the opportunity to check out the spacecraft and payload, try on their custom-made flight suits and review safety procedures.

Discovery's STS-119 mission to the International Space Station is targeted to lift off at 7:32 a.m. EST, Feb. 12.

Saturday, January 10, 2009

Next Mission Milestone Met STS-119

In the Vehicle Assembly Building at NASA's Kennedy Space Center in Florida, the joining of space shuttle Discovery, its external fuel tank and solid rocket boosters continues over the weekend.

Discovery's 3.4-mile journey to Kennedy's Launch Pad 39A is scheduled to begin 4 a.m. EST Jan. 14. The trip will take approximately six hours.

STS-119's mission payload, which includes the S6 truss segment and U.S. solar arrays, has been packed into a transport canister and is set for delivery to the pad Jan. 11.

At NASA's Johnson Space Center in Houston the STS-119 crew continues training for the additional powering up of the International Space Station.

Commander Lee Archambault will lead a crew of seven, along with Pilot Tony Antonelli, and Mission Specialists Joseph Acaba, John Phillips, Steve Swanson, and Richard ArnoldJapan Aerospace Exploration Agency astronaut Koichi Wakata.

The astronauts are expected to be at Kennedy for a full-dress rehearsal called the Terminal Countdown Demonstration Test, or TCDT, Jan. 19-21. They will have the opportunity to check out the spacecraft and payload, try on their custom-made flight suits and review safety procedures.

Discovery's STS-119 mission to the International Space Station is targeted to lift off at 7:32 a.m. EST, Feb. 12.

New NASA Balloon Successfully Flight-Tested Over Antarctica

NASA and the National Science Foundation have successfully launched and demonstrated a newly designed super pressure balloon prototype that may enable a new era of high-altitude scientific research. The super-pressure balloon ultimately will carry large scientific experiments to the brink of space for 100 days or more.

This seven-million-cubic-foot super-pressure balloon is the largest single-cell, super-pressure, fully-sealed balloon ever flown. When development ends, NASA will have a 22 million-cubic-foot balloon that can carry a one-ton instrument to an altitude of more than 110,000 feet, which is three to four times higher than passenger planes fly.

"This flight test is a very important step forward in building a new capability for scientific ballooning based on sound engineering and operational development," said W. Vernon Jones, senior scientist for suborbital research at NASA Headquarters in Washington. "The team has further work to do to enable the super pressure balloon to lift a one-ton instrument to a float altitude of 110,000 feet, but the team has demonstrated they are on the right path."

Ultra-long duration missions using the super pressure balloon cost considerably less than a satellite and the scientific instruments flown can be retrieved and launched again, making them ideal very-high altitude research platforms.

The test flight was launched Dec. 28, 2008, from McMurdo Station, which is the National Science Foundation's logistics hub in Antarctica. The balloon reached a float altitude of more than 111,000 feet and continues to maintain it in its 11th day of flight. The flight tested the durability and functionality of the scientific balloon's unique pumpkin-shaped design and novel material. The material is a special lightweight polyethylene film, about the thickness of ordinary plastic food wrap.

"Our balloon development team is very proud of the tremendous success of the test flight and is focused on continued development of this new capability to fly balloons for months at a time in support of scientific investigations," said David Pierce, chief of the Balloon Program Office at NASA's Wallops Flight Facility at Wallops Island, Va. "The test flight has demonstrated that 100 day flights of large, heavy payloads is a realistic goal."

In addition to the super pressure test flight, two additional long-duration balloons have been launched from McMurdo during the 2008-2009 campaign. The University of Hawaii Manoa's Antarctic Impulsive Transient Antenna launched Dec. 21, 2008, and is still aloft. Its radio telescope is searching for indirect evidence of extremely high-energy neutrino particles possibly coming from outside our Milky Way galaxy.

The University of Maryland's Cosmic Ray Energetics and Mass, or CREAM IV, experiment launched Dec. 19, 2008, and landed Jan. 6, 2009. The CREAM investigation was used to directly measure high energy cosmic-ray particles arriving at Earth after originating from distant supernova explosions elsewhere in the Milky Way galaxy.

The super-pressure balloon was highlighted in the National Research Council's decadal survey "Astronomy and Astrophysics in the New Millennium," and will play an important role in providing inexpensive access to the near-space environment for science and technology.

NASA and the National Science Foundation conduct an annual scientific balloon campaign during the Antarctic summer. The National Science Foundation manages the U.S. Antarctic Program and provides logistic support for all U.S. scientific operations in Antarctica.

The Wallops Flight Facility is a division of NASA's Goddard Space Flight Center in Greenbelt, Md. Wallops manages NASA's scientific balloon program for the Science Mission Directorate. Launch operations are conducted by the Columbia Scientific Balloon Facility of Palestine, Texas, which is managed for NASA by the Physical Science Laboratory of New Mexico State University in Las Cruces.

Dead Stars Tell Story of Planet Birth

Astronomers have turned to an unexpected place to study the evolution of planets -- dead stars.

Observations made with NASA's Spitzer Space Telescope reveal six dead "white dwarf" stars littered with the remains of shredded asteroids. This might sound pretty bleak, but it turns out the chewed-up asteroids are teaching astronomers about the building materials of planets around other stars.

So far, the results suggest that the same materials that make up Earth and our solar system's other rocky bodies could be common in the universe. If the materials are common, then rocky planets could be, too.

"If you ground up our asteroids and rocky planets, you would get the same type of dust we are seeing in these star systems," said Michael Jura of the University of California, Los Angeles, who presented the results today at the American Astronomical Society meeting in Long Beach, Calif. "This tells us that the stars have asteroids like ours -- and therefore could also have rocky planets." Jura is the lead author of a paper on the findings accepted for publication in the Astronomical Journal.

Asteroids and planets form out of dusty material that swirls around young stars. The dust sticks together, forming clumps and eventually full-grown planets. Asteroids are the leftover debris. When a star like our sun nears the end of its life, it puffs up into a red giant that consumes its innermost planets, while jostling the orbits of remaining asteroids and outer planets. As the star continues to die, it blows off its outer layers and shrinks down into a skeleton of its former self -- a white dwarf.

Sometimes, a jostled asteroid wanders too close to a white dwarf and meets its demise -- the gravity of the white dwarf shreds the asteroid to pieces. A similar thing happened to Comet Shoemaker Levy 9 when Jupiter's gravity tore it up, before the comet ultimately smashed into the planet in 1994.

Spitzer observed shredded asteroid pieces around white dwarfs with its infrared spectrograph, an instrument that breaks light apart into a rainbow of wavelengths, revealing imprints of chemicals. Previously, Spitzer analyzed the asteroid dust around two so-called polluted white dwarfs; the new observations bring the total to eight.

"Now, we've got a bigger sample of these polluted white dwarfs, so we know these types of events are not extremely rare," said Jura.

In all eight systems observed, Spitzer found that the dust contains a glassy silicate mineral similar to olivine and commonly found on Earth. "This is one clue that the rocky material around these stars has evolved very much like our own," said Jura.

The Spitzer data also suggest there is no carbon in the rocky debris -- again like the asteroids and rocky planets in our solar system, which have relatively little carbon.

A single asteroid is thought to have broken apart within the last million years or so in each of the eight white-dwarf systems. The biggest of the bunch was once about 200 kilometers (124 miles) in diameter, a bit larger than Los Angeles County.

Jura says the real power of observing these white dwarf systems is still to come. When an asteroid "bites the dust" around a dead star, it breaks into very tiny pieces. Asteroid dust around living stars, by contrast, is made of larger particles. By continuing to use spectrographs to analyze the visible light from this fine dust, astronomers will be able to see exquisite details -- including information about what elements are present and in what abundance. This will reveal much more about how other star systems sort and process their planetary materials.

"It's as if the white dwarfs separate the dust apart for us," said Jura.

Other authors are Ben Zuckerman at the University of California, Los Angeles, and Jay Farihi at Leicester University, England.

This research was funded by NASA and the National Science Foundation. 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, also in Pasadena. Caltech manages JPL for NASA. For more information about Spitzer, visit http://www.spitzer.caltech.edu/spitzer and http://www.nasa.gov/spitzer .

NASA Selects Hampton Firms For Engineering Support

NASA has selected Analytical Services & Materials Inc., and Analytical Mechanics Associates Inc., both of Hampton, Va., to provide analysis, systems engineering and research support for NASA's Langley Research Center in Hampton.

The fixed price, multiple award blanket purchase agreements have an aggregate maximum value of $100 million during a period of five years.

The Hampton firms will provide scientific, engineering, and design and development activities in aerodynamics, mechanical, structural, thermal, propulsion, fluid systems, electrical and electronics, avionics and controls, instrumentation and advanced sensor, and manufacturing technology.

The work will be performed at Langley and at contractor locations.

For information about the Langley Research Center, visit:

Wednesday, January 7, 2009

Space Station Jettison of Debris



You do realize that blowing the satellite out into space is much better then letting it enter the atmosphere since many contain hazardous materials that don't actually burn up but disperse into the atmosphere.

Further just letting an object wander into the atmosphere wont mean that it will burn up. Many objects, including man made, become terrestrial rather then burning up. Unless you are suggesting those are actually UFOs.