By Ron Cowen
Astronomers have identified a type of supernova as the main source of space dust, one of the building blocks of stars and planets.
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A core-collapse supernova—the most common type of exploding star—is triggered when a massive star can no longer resist the power of its own gravity. The star’s core implodes while its outer layers blast into space. The material that’s expelled in this way eventually condenses, and new observations suggest that most cosmic dust comes from this condensation.