Distances to the Remnants of Recent Supernova Explosions in the Milky Way
Some types of stars end their lives in highly energetic explosions known as supernovae. Over the past 75 years, astronomers have discovered nearly three hundred remnants of supernovae in our Milky Way galaxy, and over a 1000 remnants in several neighboring galaxies. Many key properties of supernova remnants depend on knowing the remnant's distance from us, a quantity that is hard to accurately measure.
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