September 10, 2008 - National Geographic News
Stars have onion-like layers that blow off in fiery explosions before a final killing blow—a supernova—turns them into black holes, according to a new theory of star death.
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Using two telescopes at Cerro Tololo Inter-American Observatory and the International Gemini Observatory in Chile, Smith took another look at both the Homunculus Nebula and another shell of cast-off material, estimated to be a thousand years old.
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