Lockheed Martin And NASA Ames Team Selected To Design New SolarLockheed Martin And NASA Ames Team Selected To Design New Solar Mission
by Staff Writers In the recent announcement, NASA selected six missions for study. Two of them will eventually be chosen to move forward to development, with each mission capped at $105 million. IRIS fills a crucial gap in our ability to advance Sun-Earth connection studies by tracing the flow of energy and plasma through a dynamic interface region between the solar corona and heliosphere, where all but a few percent of the non-radiative energy leaving the Sun is converted to heat and radiation. Magnetic fields and plasma exert comparable forces in this region, and IRIS is uniquely suited to provide the observations necessary to pinpoint the physical forces at work in this little understood piece of real estate near the surface of the Sun. "With IRIS we have a unique opportunity to work with our colleagues at NASA Ames to pool the expertise of each of our organizations and put together a nimble and robust design for a mission that will provide significant missing pieces in our understanding of energy transport on the Sun," said Dr. Alan Title, Lockheed Martin Advanced Technology Center solar physicist and IRIS principal investigator. "The complex processes and enormous contrasts of density, temperature and magnetic field within this interface region require instrument and modeling capabilities that are only now within our reach." "Ames is pleased to be involved in these innovative, inexpensive Small Explorer mission proposals that promise to open new windows of understanding into our world and universe," said Ames Director S. Pete Worden. "We're looking forward to teaming with the principalinvestigators to boost our proposals into selection for launch." The proposed IRIS spacecraft will fly in a Sun-synchronous polar orbit for continuous solar observations on a two-year mission. It will obtain ultraviolet spectra and images with high resolution (1/3 arcsec) - with a cadence of as little as one second apart - focused on the chromosphere and the transition region. Spectra will cover temperatures from 4,500 K to 107 K, and images covering temperatures from 4,500 to 65,000 K. 22:52 - 11/6/2008 - Comment {yok} - Post CommentNASA Scientists Find Infant Solar System Awash in CarbonS The star and its emerging solar system are less than 20 million years old, and planets may have already formed. The abundance of carbon gas in the remaining debris disk indicates that the star's planets could be exotic, carbon-rich worlds of graphite and methane. Or conversely, the scientists say, Beta Pictoris and its environs might resemble our own solar system in its early days.
A team led by Dr. Aki Roberge of NASA Goddard Space Flight Center in Greenbelt, Md., presents the FUSE observation in the June 8 issue of Nature. The new measurements make Beta Pictoris the first disk of its kind whose gas has been comprehensively studied. The discovery settles a long-standing scientific mystery about how the gas has lingered in this debris disk yet raises new questions about the development of solar systems.
"There is much, much more carbon gas than anyone expected," said Roberge, a NASA Postdoctoral Fellow and lead author on the Nature report. "Could this be what our own solar system looked like when it was young? Are we seeing the making of exotic, new worlds? Either prospect is fascinating."
Image: In the Beta Pictoris Disk. Artist's conception of the dust and gas disk surrounding the star Beta Pictoris. A giant planet may have already formed and terrestrial planets may be forming. The inset panels show two possible outcomes for mature terrestrial planets around Beta Pic. The top one is a water-rich planet similar to the Earth; the bottom one is a carbon-rich planet, with a smoggy, methane-rich atmosphere similar to that of Titan, a moon of Saturn. Credit: NASA/FUSE/Lynette Cook
Beta Pictoris, about 60 light years away, is 1.8 times more massive than our sun. This young star's disk was discovered in 1984. Earlier observations have hinted that a Jupiter-like planet may have already formed in this disk and that rocky terrestrial planets may be forming. Such planets would be too small and faint to observe with current instruments.
The carbon gas detected by FUSE comes from unseen asteroids or comets orbiting the star. These collide with each other, releasing material in a process similar to how NASA's Deep Impact probe liberated dust and gas from within comet Tempel 1 last year. The terrestrial planets in our solar system---Mercury, Venus, Earth and Mars---formed from the collision of smaller planetary bodies such as asteroids about 5 billion years ago. During the few hundred million years after Earth was formed, asteroids and comets might have smashed into our planet to deliver virtually all of the water and organic material we see today. These materials are the building blocks of life on Earth.
Asteroids and comets orbiting Beta Pictoris might contain large amounts of carbon-rich material, such as graphite and methane. Planets forming from or impacted by such bodies would be very different from those in our solar system and might have methane-rich atmospheres, like Titan, a moon of Saturn.
"We have learned in the past ten years is that our galaxy is filled with other solar systems, and each one is different from the next," said Dr. Marc Kuchner of NASA Goddard, an expert on extra-solar planets. "If carbon-rich worlds are forming in Beta Pictoris, they might be covered with tar and smog, with mountains made of giant diamonds. Life on such a planet is not implausible, but it certainly would be exotic."
A second possibility is that Beta Pictoris might be similar to our solar system long ago. While local asteroids and comets don't seem carbon-rich today, some research suggests that certain meteorites called enstatite chondrite meteorites formed in a carbon-rich environment, and some scientists speculate that Jupiter has a carbon core.
Image: The Debris Disk Around Beta Pictoris. This image of the circumstellar disk around Beta Pictoris shows (in false colors) the light reflected by dust around the young star at infrared wavelengths. The Beta Pic disk is very likely an infant solar system in the process of forming terrestrial planets. Credit: Jean-Luc Beuzit, et al. Grenoble Observatory, European Southern Observatory
"We might be observing processes that occurred early in our solar system's development," said Nature co-author Dr. Alycia Weinberger of the Carnegie Institution of Washington. The mere presence of gas in the Beta Pictoris disk has been a mystery. Theoretical models predict that intense light from the young star should rapidly blow the gas away. The overabundance of carbon gas, discovered now for the first time, solves this mystery. Carbon has special properties that keep the gas in orbit around the star.
Other co-authors on the report are Dr. Paul Feldman, Johns Hopkins University, Baltimore; and Drs. Magali Deleuil and Jean-Claude Bouret, Laboratoire d'Astrophysique de Marseille in France. The FUSE project is a NASA Explorer mission developed in cooperation with the French and Canadian space agencies by Johns Hopkins University in Baltimore; University of Colorado, Boulder; and University of California, Berkeley. NASA Goddard manages the program for NASA's Science Mission Directorate. 21:40 - 29/8/2006 - Comment {yok} - Post CommentHoney, I Shrunk the Solar System
The International Astronomical Union, wrapping up its meeting in Prague, Czech Republic, has resolved one of the most hotly-debated topics in the cosmos by approving a specific definition that gives our solar system eight planets, instead of the nine most of us grew up memorizing.
NASA has already visited all eight planets that retain their official title: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune. In addition, the agency has its New Horizons spacecraft en route to Pluto, which the astronomical union has designated as the prototype for a new class of celestial objects, to be called "dwarf planets."
"NASA will, of course, use the new guidelines established by the International Astronomical Union," said Dr. Paul Hertz, Chief Scientist for the Science Mission Directorate at NASA Headquarters. "We will continue pursuing exploration of the most scientifically interesting objects in the solar system, regardless of how they are categorized."
Ceres, which orbits in a belt between Mars and Jupiter and is the largest known asteroid, is one of those interesting objects. In 2007, NASA will launch the Dawn spacecraft on a mission to study Ceres, which the astronomers have placed in the dwarf planet category, alongside Pluto. The dwarf planet family also includes 2003 UB313, nicknamed "Xena." When Dr. Mike Brown of Caltech and his colleagues announced last summer that they'd discovered the object, which is bigger and farther away than Pluto, many astronomers decided it was time to figure out once and for all, "What exactly is a planet, anyway?"
Here's how it all shakes out. The International Astronomical Union has decided that, to be called a planet, an object must have three traits. It must orbit the sun, be massive enough that its own gravity pulls it into a nearly round shape, and be dominant enough to clear away objects in its neighborhood.
To be admitted to the dwarf planet category, an object must have only two of those traits -- it must orbit the sun and have a nearly round shape. And no, moons don't count as dwarf planets. In addition to Pluto, Ceres and 2003 UB313, the astronomical union has a dozen potential "dwarf planets" on its watchlist.
What's to become of the other objects in our solar system neighborhood, the ones that are not planets, not dwarf planets and not moons? The organization has decided that most asteroids, comets and other small objects will be called "small solar-system bodies." Despite the establishment of these three distinct categories, there are bound to be gray areas. As technologies improve and more objects are found, the International Astronomical Union will set up a process to decide which of the three categories are most appropriate for specific objects.
Even before the discovery of Xena, not all was calm in the planetary world. There was debate after Clyde Tombaugh discovered Pluto in 1930. With its small size, distant location and odd orbit, some questioned whether Pluto was really a planet or just an icy remnant of the planet-forming process. That issue has been resolved by the International Astronomical Union. Among those most keenly following the debate -- Mike Brown, who has been awaiting word on Pluto and the object he found, Xena.
"I'm of course disappointed that Xena will not be the tenth planet, but I definitely support the IAU in this difficult and courageous decision," said Brown. "It is scientifically the right thing to do, and is a great step forward in astronomy."
Although the revamping of our solar system might seem unsettling, it's really nothing new. In fact, when Ceres was first discovered in 1801, it was called a planet, as were several similar objects found later. But when the count kept on growing, astronomers decided "enough is enough," and they demoted Ceres and its siblings, placing them in a new category, called asteroids. 21:33 - 29/8/2006 - Comment {yok} - Post Comment
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cientists using NASA's Far Ultraviolet Spectroscopic Explorer, or FUSE, have discovered abundant amounts of carbon gas in a dusty disk surrounding a well-studied young star named Beta Pictoris. 
If you woke up Thursday morning and sensed something was different about the world around you, you're absolutely right. Pluto is no longer a planet.