NGC 6822

galaxy

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Last updated

July 1, 2026

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NGC 6822, also known as Barnard's Galaxy, is a small, irregular galaxy located approximately 2 million light-years away in the constellation Sagittarius. It was first recognized as a separate galaxy by Edwin Hubble in the early 1920s. Hubble detected Cepheid variable stars within NGC 6822, which allowed him to estimate its distance and confirm it was far beyond the Milky Way.1

This galaxy contains five diffuse nebulae, known as H II regions, which are glowing clouds of ionized hydrogen, similar to those found in our own galaxy. NGC 6822 is notable for its low metallicity and its role in early extragalactic astronomy, helping to establish the understanding that the universe is populated by numerous galaxies.1

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Hubble’s discovery of extragalactic objects
…the small, irregular cloudlike object NGC 6822 that varied in luminosity, and he suspected that they might include Cepheids. After considerable effort, he determined that 11 of them were in fact Cepheid variables, with properties indistinguishable from those of normal Cepheids in the Milky Way Galaxy and in the Magellanic…
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…the small, irregular cloudlike object NGC 6822 that varied in luminosity, and he suspected that they might include Cepheids. After considerable effort, he determined that 11 of them were in fact Cepheid variables, with properties indistinguishable from those of normal Cepheids in the Milky Way Galaxy and in the Magellanic…
Read More