More than 500,000 stars blaze red, white, and blue in this image from NASA’s Hubble Space Telescope, released in celebration of the United States’ 250th anniversary. The image showcases Messier 3 (M3), one of the Milky Way galaxy’s most massive globular clusters, or spherical collections of gravitationally bound stars. Globular clusters are made up of ancient stars that formed at roughly the same time from the same cloud of gas, giving those stars similar ages. Around 150 known globular clusters are sprinkled around the outer regions of the Milky Way.
