Asteroid Shaves Past Earth's Atmosphere

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<b>Asteroid Shaves Past Earth's Atmosphere </b><br /><br />LINK<br /><br />The closest observed asteroid yet to skim past the Earth without hitting the atmosphere, was reported by astronomers on Sunday.<br /><br />The previously unknown object, spanning five to 10 metres across, has been named 2004 FU162. It streaked across the sky just 6500 kilometres - roughly the radius of the Earth - above the ground on 31 March, although details have only now emerged.<br /><br />The MIT Lincoln Laboratory's asteroid-hunting LINEAR telescope in Socorro, New Mexico,US, observed the new object four times over a 44-minute period, several hours before its closest approach in March.<br /><br />Lincoln astronomers, who have discovered over 40,000 asteroids and comets since 1980, quickly recognised the object came exceptionally close, and posted their findings for confirmation on a web page run by the Minor Planet Center at the Harvard-Smithsonian Center for Astrophysics.<br /><br />However, by the time it was posted the object had moved into the daytime sky, so follow-up observations were impossible and the listing was quickly removed. A search for prior observations yielded no results.<br /><br /><br />Dissipated harmlessly <br /><br /><br />Despite having only four positions for the object, Steven Chesley of NASA’s Jet Propulsion Laboratory was able to calculate its orbit because it was moving rapidly across the sky.<br /><br />He also calculated that the encounter with the Earth shifted the asteroid's orbit closer towards the Sun. Previously orbiting the Sun once a year in an orbit that ranged as far inside the Earth's orbit as outside, 2004 FU162 now has a nine-month orbit centred closer to Venus than the Earth. The Minor Planet Center published Chesley’s results on Sunday in its electronic circular.<br /><br />"This was an extraordinarily close encounter and so the orbital change was quite extraordinary. 2004 FU162 was