Big bang's afterglow reveal birthplace of comets
00:01 02 December 2008 by Rachel Courtland
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A vast reservoir of comets that is too far away to see might be detectable in maps of radiation left over from the big bang, a new study suggests.
Comets that take longer than 200 years to orbit the Sun come from all directions in the sky. That has long led scientists to believe that they were nudged out of a diffuse halo of icy objects that surrounds the solar system
astronomers believe it has two components. Based on observations of long-period comets, an outer portion seems to extend from 20,000 to 200,000 astronomical units from the Sun (where 1 AU is the Earth-Sun distance).
Solar system models also predict the existence of an inner s that stretches some 3000 to 20,000 AU from the Sun. But there is less evidence for this s - most passing stars are too distant to jostle the inner halo and dislodge comets. Only a few recently spotted objects, such as the icy bodies 2006 SQ372Movie Camera and Sedna, point to its existence.
the first radiation emitted in the universe after the
big bang.