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Bill Gray

Bill Gray is the creator of the Guide astrometry software, which is used by both professional and amateur astronomers worldwide to track Near-Earth Objects, asteroids, minor planets and comets.

Latest Blog Posts

Comet ISON: 30% chance of awesome, 60% chance of that being wrong

Posted 2012/09/25 12:15 CDT | 10 comments

A very interesting comet has recently been discovered -- interesting because it will nearly graze the Sun in August 2013 and then approach Earth closely the following December. Whether it will turn out to be a great comet is impossible to know.

Chang'e 2: The Full Story

Posted 2012/08/25 10:55 CDT | 4 comments

An update on China's second lunar orbiter, Chang'e 2, which is now heading for asteroid Toutatis.

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