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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 Articles
Comet ISON: 30% chance of awesome, 60% chance of that being wrong
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
An update on China's second lunar orbiter, Chang'e 2, which is now heading for asteroid Toutatis.