This NASA/ESA Hubble Space Telescope image shows four globular clusters in the dwarf galaxy Fornax.
New observations of the clusters – large balls of stars that orbit the centers of galaxies – show they are very similar to those found in our galaxy, the Milky Way. The finding is at odds with leading theories on how these clusters form – in these theories, globular clusters should be nestled among large quantities of old stars – and so the mystery of how these objects came to exist deepens.
Left to right: Fornax 1, Fornax 2, Fornax 3 and Fornax 5. Their positions within the galaxy are shown in image heic1425g.
Image credit: NASA, ESA, S. Larsen (Radboud University, the Netherlands)
Note: For more information, see The Riddle of the Missing Stars - Hubble Observations Cast Further Doubt on How Globular Clusters Formed.