Feb 17 2010
From The Space Library
RELEASE: 10-167
NASA FINDS SUPER HOT PLANET WITH UNIQUE COMET-LIKE TAIL
WASHINGTON -- Astronomers using NASA's Hubble Space Telescope have confirmed the existence of a baked object that could be called a "cometary planet. The gas giant planet, named HD 209458b, is orbiting so close to its star that its heated atmosphere is escaping into space. Observations taken with Hubble's Cosmic Origins Spectrograph (COS) suggest powerful stellar winds are sweeping the cast-off atmospheric material behind the scorched planet and shaping it into a comet-like tail. "Since 2003 scientists have theorized the lost mass is being pushed back into a tail, and they have even calculated what it looks like, said astronomer Jeffrey Linsky of the University of Colorado in Boulder, leader of the COS study. We think we have the best observational evidence to support that theory. We have measured gas coming off the planet at specific speeds, some coming toward Earth. The most likely interpretation is that we have measured the velocity of material in a tail. The planet, located 153 light years from Earth, weighs slightly less than Jupiter but orbits 100 times closer to its star than the Jovian giant. The roasted planet zips around its star in a short 3.5 days. In contrast, our solar system's fastest planet, Mercury, orbits the sun in 88 days. The extrasolar planet is one of the most intensely scrutinized, because it is the first of the few known alien worlds that can be seen passing in front of, or transiting, its star. Linsky and his team used COS to analyze the planet's atmosphere during transiting events. During a transit, astronomers study the structure and chemical makeup of a planet's atmosphere by sampling the starlight that passes through it. The dip in starlight because of the planet's passage, excluding the atmosphere, is very small, only about 1.5 percent. When the atmosphere is added, the dip jumps to 8 percent, indicating a bloated atmosphere. COS detected the heavy elements carbon and silicon in the planet's super-hot 2,000 degrees Fahrenheit atmosphere. This detection revealed the parent star is heating the entire atmosphere, dredging up the heavier elements and allowing them to escape the planet. The COS data also showed the material leaving the planet was not all traveling at the same speed. We found gas escaping at high velocities, with a large amount of this gas flowing toward us at 22,000 miles per hour, Linsky said. This large gas flow is likely gas swept up by the stellar wind to form the comet-like tail trailing the planet. Hubble's newest spectrograph has the ability to probe a planet's chemistry at ultraviolet wavelengths not accessible to ground-based telescopes. COS is proving to be an important instrument for probing the atmospheres of hot Jupiters like HD 209458b. Another Hubble instrument, the Space Telescope Imaging Spectrograph (STIS), observed the planet in 2003. The STIS data showed an active, evaporating atmosphere, and a comet-tail-like structure was suggested as a possibility. But STIS wasn't able to obtain the spectroscopic detail necessary to show a tail, or an Earthward-moving component of the gas, during transits. The tail was detected for the first time because of the unique combination of very high ultraviolet sensitivity and good spectral resolution provided by COS. Although this extreme planet is being roasted by its star, it won't be destroyed anytime soon. It will take about a trillion years for the planet to evaporate, Linsky said. The results appeared in the July 10 issue of The Astrophysical Journal. The Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency. NASA's Goddard Space Flight Center in Greenbelt, Md., manages the telescope. The Space Telescope Science Institute, operated for NASA by the Association of Universities for Research in Astronomy, Inc. in Washington, conducts Hubble science operations. For illustrations and more information about HD 209458b, visit: http://www.nasa.gov/hubble
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RELEASE: 10-098
NASA, EPA EXTEND ENVIRONMENTAL AND EARTH SCIENCE COLLABORATIONS
WASHINGTON -- NASA Administrator Charles Bolden and U.S. Environmental Protection Agency Administrator Lisa P. Jackson signed a Memorandum of Agreement on Monday to promote and continue collaboration between the two agencies in environmental and Earth sciences and applications. The signing ceremony took place at the Howard University Middle School of Mathematics and Science (MS)? in Washington. Following the ceremony, both administrators met with students to discuss the importance of science and engineering education. "Our agencies have a remarkable opportunity to tackle a variety of environmental issues together, said Administrator Bolden. Involving students in Earth science and climate research at an early age will encourage a stronger sense of stewardship toward our home planet. The agreement renews a broad partnership to promote joint efforts to improve environmental and Earth science research, technology, environmental management, and the application of Earth science data, models and technology in environmental decision-making. "Our health and the health of our environment depend on continuous scientific exploration and innovation. EPA is proud to work with NASA to engage and inspire the next generation of scientists and engineers who will carry our work forward, said Jackson. America's young people are stepping up in this effort because they know what's at stake now and in the future, and they see the opportunities for the next great, game-changing discovery that will improve their lives and the lives of others. Both agencies have been involved in projects and activities for many years. In 2005, the first Memorandum of Agreement was signed to formalize the partnership. Areas of collaboration include climate change, air quality, and water. The re-invigorated partnership focuses on science leadership to motivate continued exploration, innovation and protection of our home planet. NASA's Earth Science program advances knowledge of the integrated Earth system. NASA research encompasses the global atmosphere, the global oceans including sea ice, land surfaces including snow and ice, ecosystems, and interactions between the atmosphere, oceans, land, and ecosystems, including humans. NASA maintains the world's largest contingent of dedicated Earth scientists and engineers in leading and assisting other agencies in preserving the planet's environment. NASA operates 14 satellite missions as well as aircraft and surface-based instruments to sustain simultaneous observations to unravel the complexity of the integrated Earth system. In addition, the agency supports advanced computing and modeling capabilities and maintains the world's largest scientific data and information system for collecting, processing, archiving, and distributing Earth system data to worldwide users. The EPA's mission is to protect human health and the environment. One key component is the agency's Advanced Monitoring Initiative. The initiative's goal is to improve our nation's understanding of how environmental factors affect human health and ecological well being. Projects within the initiative enable better understanding of how to provide improved data to support and enhance environmental policy, management, and decision making. The agency strives to develop new data products, models and tools to assist decision makers and the public in understanding today's complex environmental issues.
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RELEASE: 10-174
NASA TELESCOPE FINDS ELUSIVE BUCKYBALLS IN SPACE FOR FIRST TIME
WASHINGTON -- Astronomers using NASA's Spitzer Space Telescope have discovered carbon molecules, known as buckyballs, in space for the first time. Buckyballs are soccer-ball-shaped molecules that were first observed in a laboratory 25 years ago. They are named for their resemblance to architect Buckminster Fuller's geodesic domes, which have interlocking circles on the surface of a partial sphere. Buckyballs were thought to float around in space, but had escaped detection until now. "We found what are now the largest molecules known to exist in space, said astronomer Jan Cami of the University of Western Ontario, Canada, and the SETI Institute in Mountain View, Calif. We are particularly excited because they have unique properties that make them important players for all sorts of physical and chemical processes going on in space. Cami authored a paper about the discovery that will appear online Thursday in the journal Science. Buckyballs are made of 60 carbon atoms arranged in three-dimensional, spherical structures. Their alternating patterns of hexagons and pentagons match a typical black-and-white soccer ball. The research team also found the more elongated relative of buckyballs, known as C70, for the first time in space. These molecules consist of 70 carbon atoms and are shaped more like an oval rugby ball. Both types of molecules belong to a class known officially as buckminsterfullerenes, or fullerenes. The Cami team unexpectedly found the carbon balls in a planetary nebula named Tc 1. Planetary nebulas are the remains of stars, like the sun, that shed their outer layers of gas and dust as they age. A compact, hot star, or white dwarf, at the center of the nebula illuminates and heats these clouds of material that has been shed. The buckyballs were found in these clouds, perhaps reflecting a short stage in the star's life, when it sloughs off a puff of material rich in carbon. The astronomers used Spitzer's spectroscopy instrument to analyze infrared light from the planetary nebula and see the spectral signatures of the buckyballs. These molecules are approximately room temperature; the ideal temperature to give off distinct patterns of infrared light that Spitzer can detect. According to Cami, Spitzer looked at the right place at the right time. A century from now, the buckyballs might be too cool to be detected. The data from Spitzer were compared with data from laboratory measurements of the same molecules and showed a perfect match. "We did not plan for this discovery, Cami said. But when we saw these whopping spectral signatures, we knew immediately that we were looking at one of the most sought-after molecules. In 1970, Japanese professor Eiji Osawa predicted the existence of buckyballs, but they were not observed until lab experiments in 1985. Researchers simulated conditions in the atmospheres of aging, carbon-rich giant stars, in which chains of carbon had been detected. Surprisingly, these experiments resulted in the formation of large quantities of buckminsterfullerenes. The molecules have since been found on Earth in candle soot, layers of rock and meteorites. The study of fullerenes and their relatives has grown into a busy field of research because of the molecules' unique strength and exceptional chemical and physical properties. Among the potential applications are armor, drug delivery and superconducting technologies. Sir Harry Kroto, who shared the 1996 Nobel Prize in chemistry with Bob Curl and Rick Smalley for the discovery of buckyballs, said, This most exciting breakthrough provides convincing evidence that the buckyball has, as I long suspected, existed since time immemorial in the dark recesses of our galaxy. Previous searches for buckyballs in space, in particular around carbon-rich stars, proved unsuccessful. A promising case for their presence in the tenuous clouds between the stars was presented 15 years ago, using observations at optical wavelengths. That finding is awaiting confirmation from laboratory data. More recently, another Spitzer team reported evidence for buckyballs in a different type of object, but the spectral signatures they observed were partly contaminated by other chemical substances.
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