The Crab Nebula is a remnant of a supernova explosion that was observed on Earth in 1054. The distance to the nebula is about 1.5 kpc. How long ago did the star explode? At what minimum distance from the Earth is the place where this outbreak can be observed at the moment (in 2018)?
Approximately 5900 years ago; at a distance of approximately 2018-1054 = 964 sv. g.
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