It may not be filled Hollywood's finest, but this super cluster is a magnet for hot, young stars.

Known as Westerlund 1, this super star cluster sits inside the Milky Way galaxy and is about 1,000 times closer than any other super cluster known. Westerlund 1 can be found in the southern constellation Ara (the Altar).

Hundreds of thousands of stars are crammed inside Westerlund 1, some as bright as 1 million Suns while others swell up until their diameters span the entire orbit of Saturn (about 2,000 times larger than the Sun). Astronomers believe the super star cluster contains is about 100,000 times as massive as the Sun and packed in an area about six light-years across, making it the most massive compact cluster known to date.

Researchers used telescopes at the European Southern Observatory in La Silla, Chile to make this composite image of Westerlund 1. Most of the stars, they said, appear 30 to 40 times as massive as the Sun, leading astronomers to believe the cluster is between 3.5 million and five million years old.

-- SPACE.com Staff

Credit: ESO