Deep-Space Photos: Hubble's Greatest Hits

Stellar Spotlight
Messier 70 is a globular cluster like Messier 9, though its stars are packed more tightly. The denser a cluster the brighter it is, and Messier 70 is thus easy for backyard astronomers to spot. Indeed, if anything, it will likely get brighter over the course of cosmic time, since it has experienced what's known as a core collapse, causing even more stars to huddle near its center.

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