A ROCK COMET? That is what astronomers are stating they have confirmed the Sun grazing Phaethon - formerly an asteroid behaving at times like a comet - to be using NASA's STEREO spacecraft.
Using STEREO which consists of two spacecraft that observe the Sun from different angles, including the far side of the Sun as seen from Earth, astronomers observed a tail. Previous attempts to capture Phaethon in the act of having a tail failed because until STEREO, researchers could never observe the space rock as it was too close to the Sun.
STEREO caught Phaethon's tail during a close pass to the Sun as can be seen in the photo above. Researchers think that during these close approaches to the Sun the rock on the surface literally gets too hot crumbles into dust much like desert mud flats. The pressure from the Sun then causes this loose material to form the tail that is observed.
This also helps explain what fuels the Geminid Meteor Shower each December. This material from the Rock Comet flows out into space where it intersects the Earth's orbit each December giving us the great show of "falling stars".
Phaethon is believed to definitely be a 3 mile-wide asteroid due to the shape of its' orbit. But it does behave like a comet making it another addition to our solar system zoo.
Read More About It: http://www.europlanet-eu.org/epsc2013/media-press/epsc-2013-press-releases/76-epsc2013/media-press/618-epsc-2013-phaethon-confirmed-as-rock-comet-by-stereo-vision
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