The Hubble Space Telescope’s keen astronomical eye found a massive star that is actually two.

Known as Pismis 24-1, this stellar was once thought to be one of, if not the, most massive stars in the Milky Way Galaxy with a mass pinned at some 300 times that of the Sun.

But more accurate measurements by Hubble found it to be at least two stars, if not three, cutting its mass estimates in half.

Pismis 24-1 sits in a star cluster tucked at the heart of the NGC 6357 emission nebula about 8,000 light-years from Earth in the constellation Sagittarius [image].

This three-frame image shows Hubble’s resolution, first of the emission nebula, then of Pismis-24-1’s star cluster home, then the stellar pair itself.

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-- SPACE.com Staff

Credit: NASA, ESA and Jesús Maíz Apellániz (Instituto de astrofísica de Andalucía, Spain