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| Image credit: University of Arizona |
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| Meteorites Could Have Supplied the Earth with Phosphorus |
| Aug 24, 2004 - Phosphorus is central to life on Earth for many reasons; it forms the backbone of DNA and RNA, and it's an important element in many chemical processes. The questions is, how did the Earth get so much of it? Researchers from the University of Arizona believe that the meteorites that rained down early on during the formation of the Earth could have been the source. They found that many iron-nickel meteorites are rich with minerals that contain phosphorus, and propose that life could have formed around a spot where a meteorite struck the Earth. (Full Story) |
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| Image credit: NASA/JPL/SSI |
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| Cassini Completes Orbital Maneuver |
| Aug 24, 2004 - NASA's Cassini spacecraft completed a 51-minute engine burn that raised its orbit away from Saturn. When it first arrived at the Ringed Planet, Cassini passed very close to the planet and went right through the rings. On its next flyby, it'll pass outside the rings and make its first close-up flyby of Titan at a distance of only 1,200 km (746 miles) - nearly 300 times closer than its previous flyby. Cassini is expected to make 45 visits to Titan over the next 4 years, and some will be even closer. (Full Story) |
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| Image credit: ESA |
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| Martian Crater With Dunes |
| Aug 24, 2004 - This image of a Martian crater was taken by the European Space Agency's Mars Express spacecraft in May, 2004. The crater is unevenly weathered, with a gentle slope on the wind-facing side, and a steep slope on the lee-side - on Earth these features are called ‘barchanes’, and usually form in arid regions. There's a dune field on the bottom of the crater, that seems to be composed of sand of volcanic origin; how it got to the bottom of this crater is a mystery. (Full Story) |
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| Image credit: Harvard CfA |
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| Small Telescope Finds a Huge Planet |
| Aug 24, 2004 - Planet hunting has traditionally only been possible with very large telescopes, capable of detecting tiny changes around distant stars which indicate the presence of planets. But now a team of astronomers have found their first extrasolar planet using a 4-inch telescope essentially developed with off-the-shelf equipment. The new Jupiter-sized planet is located about 500 light-years away, and was discovered using the transit method, which looks for a dip in a star's brightness as a planet passes in front. The team surveyed 12,000 stars in an area half the size of the Big Dipper's bowl, and turned up 16 candidates for planets. Follow up observations with larger observatories confirmed which ones had planets, and which didn't. (Full Story) |
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| Image credit: Chandra |
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| Double Jets Around Exploded Star |
| Aug 23, 2004 - This is a detailed image of an exploded star called Centaurus A, taken by the Chandra X-Ray Observatory. The space-based observatory focused on this remnant for 1 million seconds (just over 11 days), and revealed the bright outer green ring 10 light years across which was generated by the shockwave from the supernova explosion. Two large jets extend outside this shockwave on opposite sides, and contain large quantities of silicon. This means they were formed early on in the explosion; otherwise, they'd contain mostly iron from the star's central regions. (Full Story) |
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