ULX in M83 (IMAGE) Chandra X-ray Center Caption An extraordinary outburst from a black hole -- where its X-ray output increased at least 3,000 times -- has been seen with NASA's Chandra X-ray Observatory in the galaxy M83. Chandra observed what is called a ULX, or ultraluminous X-ray source. The panel on the left features an optical view of the full M83 galaxy, while the right panel shows a close up of the region where the ULX was found with data from Chandra (pink) and Hubble (blue and yellow). The remarkable behavior of this ULX in M83 provides direct evidence for a population of older, volatile, stellar-mass black holes. Credit Credit: Left image - Optical: ESO/VLT; Close-up - X-ray: NASA/CXC/Curtin University/R. Soria et al., Optical: NASA/STScI/Middlebury College/F. Winkler et al. Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.