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Chandra Advanced Charged Coupled Imaging Spectrometer (ACIS) image (contours) and optical image (color pixels) of a newly discovered powerful X-ray source in a distant galaxy.
When viewed with an optical telescope, this galaxy appears normal. But when the Chandra X-ray Observatory observed the galaxy during calibration testing in September 1999, it discovered an unusually strong source of X-rays. Located 2.5 billion light years from Earth, the X-ray source is concentrated in the central regions of the galaxy and could be another example of a veiled black hole. This discovery adds to a growing body of evidence that our census of energetic black hole sources in galaxies is far from complete. A team of Italian and Harvard-Smithsonian scientists, led by Fabrizio Fiore of the Astronomical Observatory of Rome, and the Harvard-Smithsonian Center for Astrophysics, made the discovery. The vertical lines in the image are part of a grid to locate the source in the sky. The X-ray contours are consistent with a point-like source in the center of the galaxy. The colors in the optical image represent brightness levels. The source name is CXOUJ031238.9-765134,
which defines its position in the sky.
Credits: X-ray: NASA/CXC/SAO Optical: ESO/La Silla