A new image—taken using the Hubble Space Telescope's 'Advanced Camera For Surveys' instrument—shows a vast and colorful field of stars collectively known as NGC 1783.
Found around 150,000 light-years from Earth in the Dorado constellation, NGC 1783 is one of the largest globular clusters in the Large Magellanic Cloud (LMC): one of the more massive of the Milky Way's satellite galaxies.
Like all globular clusters, all of the stars are believed to have formed at roughly the same time—from the same nebular cloud. Despite that, there are stars of all different sizes, luminosities and stellar classifications. Some of the smallest stars have taken on a red-tinged hue, while the largest among them are blue. This has very little to do with their size, but their temperature.
By looking at the various colors, astronomers can deduce the age of the cluster, which is estimated to be between 100 and 500 million years old. Additionally, the colors help shed light on the manner in which the stars in the cluster evolved.
NASA/ESA explain further:
Overall, the cluster weighs around 170,000 times more than the Sun. (See a larger image here)