The NASA/ESA Hubble Space Telescope captured an impressive image of the irregular galaxy NGC 5253.NGC 5253 is one of the nearest of the known Blue Compact Dwarf (BCD) galaxies, and is located at a distance of about 12 million light-years from Earth in the southern constellation of Centaurus. The most characteristic signature of these galaxies is that they harbor very active star-formation regions. This is in spite of their low dust content and comparative lack of elements heavier than hydrogen and helium, which are usually the basic ingredients for star formation.
The true nature of BCD galaxies has puzzled astronomers for a long time. Numerical simulations following the current leading cosmological theory of galaxy formation, known as the Lambda Cold Dark Matter model, predict that there should be far more satellite dwarf galaxies orbiting big galaxies like the Milky Way. Astronomers refer to this discrepancy as the Dwarf Galaxy Problem.
This galaxy is considered part of the Centaurus A/Messier 83 group of galaxies, which includes the famous radio galaxy Centaurus A and the spiral galaxy Messier 83. Astronomers have pointed out the possibility that the peculiar nature of NGC 5253 could result from a close encounter with Messier 83, its closer neighbor.
This image was taken with the Hubble's Advanced Camera for Surveys, combining visible and infrared exposures. The field of view in this image is approximately 3.4 by 3.4 arcminutes. A version of this image was entered into the Hubble's Hidden Treasures image processing competition by contestant Nikolaus Sulzenauer.
The Daily Galaxy via NASA