Chandra Release - June 21, 2006

Visual Description: GRO J1655-40

The graphic contains an illustration in the main panel and a smaller inset Chandra X-ray Observatory spectrum of a binary star system called GRO J1655-40.  GRO J1655 consists of two stars orbiting each other. One of the stars is a black hole (at left) and the other is a normal star (at right), with a thin link of material between the two of them as the black hole siphons off matter from the star.  In the illustration, there is a bright blue light coming off of the area of the black hole and its disk.  The graph, or spectrum, on the lower left side represents the intensity of the X-rays emitted by the binary star system over time with little fluctuations. It indicates that turbulent winds of multimillion degree gas are swirling around the black hole. The colors in the image are predominantly blue and purple, with some red and oranges in the central area of the black hole’s disk.    As the illustration shows with the bright blue light escaping the back hole, much of the hot gas is spiraling inward toward the black hole, but about 30% is blowing away.