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Comet collision to come?


New research shows that the Earth was impacted for a few hours by a stream of dust from a potentially dangerous comet on February 4, 2011.


A telegram was issued on July 10th by the Central Bureau for Astronomical Telegrams of the International Astronomical Union announcing that the Earth got impacted for a few hours by a stream of dust from a potentially dangerous comet last February 4.


“This particular shower happens only once or twice every sixty years,” says discoverer Dr. Peter Jenniskens of the SETI Institute and NASA Ames. “The stream of dust is always there, but quite invisible just outside of Earth’s orbit. Only when the planets steer the dust in Earth’s path do we get to know it is there.”


Jenniskens has found the trail of crumbs of such a comet, which passed very close to Earth’s orbit the last time it was near the Sun. That could have been only a few hundred years ago, or many thousands. At that time, the comet released a cloud of dust which is now returning. Some dust grains return earlier than others, depending on how elongated their orbit ended up being, and the result is a continuous stream of returning dust grains. That stream is detected only when it encounters the Earth, when the meteoroids cause a brief 2-hour meteor shower.


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Lees verder: http://www.physorg.com/news/2011-08-comet-collision.html


Bron: Scientias.nl