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Giant Super-Earths Made of Diamond Are Possible

December 5, 2011 Leave a comment

A planet made of diamonds may sound lovely, but you wouldn’t want to live there.

A new study suggests that some stars in the Milky Way could harbor “carbon super-Earths” – giant terrestrial planets that contain up to 50 percent diamond.

But if they exist, those planets are likely devoid of life as we know it.

The finding comes from a laboratory experiment at Ohio State University, where researchers recreated the temperatures and pressures of Earth’s lower mantle to study how diamonds form there.

The larger goal was to understand what happens to carbon inside planets in other solar systems, and whether solar systems that are rich in carbon could produce planets that are mostly made of diamond.

Full Story: http://researchnews.osu.edu/archive/diamondplanet.htm

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NASA’s Voyager Hits New Region at Solar System Edge

December 5, 2011 Leave a comment

NASA’s Voyager 1 spacecraft has entered a new region between our solar system and interstellar space. Data obtained from Voyager over the last year reveal this new region to be a kind of cosmic purgatory. In it, the wind of charged particles streaming out from our sun has calmed, our solar system’s magnetic field is piled up, and higher-energy particles from inside our solar system appear to be leaking out into interstellar space.

“Voyager tells us now that we’re in a stagnation region in the outermost layer of the bubble around our solar system,” said Ed Stone, Voyager project scientist at the California Institute of Technology in Pasadena. “Voyager is showing that what is outside is pushing back. We shouldn’t have long to wait to find out what the space between stars is really like.”

Although Voyager 1 is about 11 billion miles (18 billion kilometers) from the sun, it is not yet in interstellar space. In the latest data, the direction of the magnetic field lines has not changed, indicating Voyager is still within the heliosphere, the bubble of charged particles the sun blows around itself. The data do not reveal exactly when Voyager 1 will make it past the edge of the solar atmosphere into interstellar space, but suggest it will be in a few months to a few years.

Full Story: http://www.jpl.nasa.gov/news/news.cfm?release=2011-372

Pair of Black Holes ‘Weigh In’ at 10 Billion Suns

December 5, 2011 Leave a comment

A team of astronomers including Karl Gebhardt and graduate student Jeremy Murphy of The University of Texas at Austin have discovered the most massive black holes to date — two monsters weighing as much as 10 billion suns and threatening to consume anything, even light, within a region five times the size of our solar system.

The research is published in the December 8 issue of the journal Nature, in a paper headlined by graduate student Nicholas McConnell and professor Chung-Pei Ma of The University of California, Berkeley.

The team measured the black holes’ masses by combining observations of the fast-moving stars at their hearts made with the giant Gemini and Keck telescopes in Hawaii with observations of their diffuse outer regions using the George and Cynthia Mitchell Spectrograph on the 2.7-meter Harlan J. Smith Telescope at The University of Texas at Austin’s McDonald Observatory.

Gebhardt and Murphy have been leading an effort to exploit the powerful Mitchell Spectrograph to study these galaxies. Earlier this year, they announced the previous record-holder black hole mass in the galaxy M87, at 6.7 billion suns.

Full Story: http://mcdonaldobservatory.org/news/releases/2011/1207.html

Allen Telescope Array Targets New Planets

December 5, 2011 Leave a comment

The Allen Telescope Array (ATA) is once again searching planetary systems for signals that would be evidence of extraterrestrial intelligence. Among its first targets are some of the exoplanet candidates recently discovered by NASA’s Kepler space telescope.

“This is a superb opportunity for SETI observations,” said Jill Tarter, the Director of the Center for SETI Research at the SETI Institute. “For the first time, we can point our telescopes at stars, and know that those stars actually host planetary systems — including at least one that begins to approximate an Earth analog in the habitable zone around its host star. That’s the type of world that might be home to a civilization capable of building radio transmitters.”

The ATA had been placed in hibernation mode last April as the result of the withdrawal of the SETI Institute’s former partner, U.C. Berkeley, due to budgetary shortfalls. Berkeley was the operator of the Hat Creek Observatory in northern California where the ATA is located. With new funding recently acquired for observatory operations, the ATA can resume SETI observations where it left off: examining the thousands of new candidate planets found by Kepler. Highest priority will be given to the handful of worlds discovered so far that are located in their star’s habitable zone: the range of orbital radii where temperatures are neither too hot nor too cold for liquid water to exist. Most astrobiologists consider that liquid water is the sine qua non for life.

Full Story: http://astronews.us/2011-12-05-1246.html

NASA’s Kepler Mission Confirms Its First Planet in Habitable Zone of Sun-like Star

December 5, 2011 Leave a comment

Image credit: NASA/Ames/JPL-Caltech

Image credit: NASA/Ames/JPL-Caltech

NASA’s Kepler mission has confirmed its first planet in the “habitable zone,” the region where liquid water could exist on a planet’s surface. Kepler also has discovered more than 1,000 new planet candidates, nearly doubling its previously known count. Ten of these candidates are near-Earth-size and orbit in the habitable zone of their host star. Candidates require follow-up observations to verify they are actual planets.

The newly confirmed planet, Kepler-22b, is the smallest yet found to orbit in the middle of the habitable zone of a star similar to our sun. The planet is about 2.4 times the radius of Earth. Scientists don’t yet know if Kepler-22b has a predominantly rocky, gaseous or liquid composition, but its discovery is a step closer to finding Earth-like planets.

Previous research hinted at the existence of near-Earth-size planets in habitable zones, but clear confirmation proved elusive. Two other small planets orbiting stars smaller and cooler than our sun recently were confirmed on the very edges of the habitable zone, with orbits more closely resembling those of Venus and Mars.

Full Story: http://www.nasa.gov/mission_pages/kepler/multimedia/images/kepler-22b.html

Veteran Space Shuttle Commander Chris Ferguson to Leave Agency

December 5, 2011 Leave a comment

Astronaut Chris Ferguson, the last commander of a space shuttle mission, has announced his plans to retire from NASA on Dec. 9. He will leave for a new job in the private sector.

“Chris has been a true leader at NASA,” NASA Administrator Charles Bolden said, “not just as a commander of the space shuttle, but also as an exemplary civil servant, a distinguished Navy officer and a good friend. I am confident he will succeed in his next career as he brings his skill and talents to new endeavors.”

Ferguson, a retired U.S. Navy captain, served as the commander for STS-135, the final flight of space shuttle Atlantis and the 135th and final mission of America’s 30-year Space Shuttle Program.

Full Story: http://www.nasa.gov/home/hqnews/2011/dec/HQ_11-404_Ferguson_Departs.html

Fastest Rotating Star Found in Neighboring Galaxy

December 5, 2011 Leave a comment

Credit: NASA, ESA, and G. Bacon (STScI)

Credit: NASA, ESA, and G. Bacon (STScI)

Astronomers have found the fastest spinning star ever discovered. The hot blue giant rotates at a dizzying 1 million miles per hour, or 100 times faster than our Sun does. The star is very close to the point at which it would be torn apart due to centrifugal forces if it spun any faster.

Two researchers at the Space Telescope Science Institute in Baltimore, Md., Selma de Mink and Daniel Lennon, are part of an international team of astronomers who used the European Southern Observatory’s Very Large Telescope at the Paranal Observatory in Chile to find the massive, bright young star, called VFTS 102. It lies in a neighboring dwarf galaxy, the Large Magellanic Cloud, about 160,000 light-years from Earth. Astronomers think that it may have had a violent past and has been ejected from a double star system by its exploding companion.

The astronomers also found that the star, which is around 25 times the mass of the Sun and about one hundred thousand times brighter, was moving through space at a significantly different speed from its neighbors.

Full Story: http://hubblesite.org/newscenter/archive/releases/2011/39/full/