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Astronomy

Accretion Disks Around Black Holes and Young Stars

Quick fact

The inner regions of an accretion disk around a black hole can reach temperatures of over 10 million Kelvin, emitting X-rays that reveal the presence of the otherwise invisible black hole.

Why this is interesting

You've seen water spiral down a drain—now imagine that on a cosmic scale, with gas and dust heating up to millions of degrees as it falls toward a black hole or a newborn star.