This is what remains of a star that went supernova in the year 1054 AD. Ancient Chinese manuscripts say that when it blew, it could be seen in the daytime sky with the brightness of the quarter moon. And almost 1,000 years later, we see the debris of the supernova explosion still moving away from the neutron star buried inside. This cloud is enriched with what the star made during its life as well as with the elements it made during the supernova blast. This material will eventually mix with vast clouds of hydrogen gas in outer space, seeding them with heavy elements, so the next generation of stars to form will start off with a richer chemistry than the generation before them.
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