For six months in 1181, a dying star left a mark in the night sky. The striking object appeared as bright as Saturn in the vicinity of the constellation Cassiopeia, and historical chronicles from ...

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Astronomers have intensely studied a zombie star lurking in the heart of supernova wreckage. Such a cosmic explosion should have destroyed this undead white dwarf star, but instead, it marked its ...

In August 1181, astronomers in China and Japan witnessed a bright "guest star" in the night sky that we now know to have been a supernova—one of just a handful of recorded supernovae in our Milky Way ...

For six months in 1181, a dying star left a mark in the night sky. The striking object appeared as bright as Saturn in the vicinity of the constellation Cassiopeia, and historical chronicles from ...

Sign up for CNN’s Wonder Theory science newsletter. Explore the universe with news on fascinating discoveries, scientific advancements and more. When a supernova ...

Sign up for CNN’s Wonder Theory science newsletter. Explore the universe with news on fascinating discoveries, scientific advancements and more. For six months in ...