Credit: NASA, ESA, and L. Bedin (STScI)

A blow-up of view of a small region of NGC 6791 imaged by NASA's Hubble Space Telescope reveals very faint white dwarfs. The hotter dwarfs are 4 billion years old and the cooler dwarfs are 6 billion years old. White dwarfs are the smoldering embers of Sun-like stars that no longer generate nuclear energy and have burned out. Their hot remaining cores radiate heat for billions of years as they slowly fade into darkness. Astronomers have used white dwarfs as a reliable measure of the ages of star clusters, because they are the relics of the first cluster stars that exhausted their nuclear fuel. NGC 6791 is located 13,300 light-years away in the constellation Lyra.

Provider: Space Telescope Science Institute

Image Source: https://hubblesite.org/contents/news-releases/2008/news-2008-25

Curator: STScI, Baltimore, MD, USA

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