Chandra Release - January 6, 2003

Visual Description: Sagittarius A*

  This Chandra image of the supermassive black hole at our Galaxy's center, a.k.a. Sagittarius A* or Sgr A*, was made from the longest X-ray exposure of that region at the time of observation. In addition to Sgr A* more than two thousand other X-ray sources were detected in the region, making this one of the richest fields ever observed. Visually, at the center of the image, there is a bright, lumpy object showing the intense X-ray radiation emanating from the Sgr A* black hole. In the surrounding area, there are several smaller, greenish-blue lumps layered throughout the image. The image appears textured, like dozens of purple, greenish-blue and white glow worms are paused in their wriggling.  Studies suggests that Sgr A*, weighing in at 3 million times the mass of the Sun, is a starved black hole, possibly because explosive events in the past have cleared much of the gas from around it. Evidence for such explosions was revealed in the image via huge lobes of 20 million-degree gas shown as large dark purple-red loops in the image at approximately the 2 o'clock and 7 o'clock positions. The ‘loops” extend over dozens of light years on either side of the black hole. They indicate that enormous explosions occurred several times over the last ten thousand years.