Last Updated: Wednesday, May 15, 2013, 15:36
When a coffee stain dries, its edges become noticeably darker and thicker, while the middle of the stain remains almost unsoiled.
Last Updated: Thursday, October 04, 2012, 16:50
Pristine material that matches comets in our own solar system have been found in a dust belt around the young star Beta Pictoris by ESA’s Herschel space observatory.
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