In this high-resolution, close-up view of Sagittarius A, more intense color corresponds to more intense radio emission. Red indicates regions were the radiation is produced from hot gas by thermal emission; electrons are so dense in these areas that they actually prevent some of the emitted light from escaping. The unique spiral-shaped feature also appears red, its arms reaching out from Sag A and ending only when they encounter a ring of dust in the inner portion of the galaxy, about 6 light years from the Galactic Center. Astronomers still do not understand why the spiral exists. It may be caused by material flowing out from the Galactic Center, such as a jet emanating from a black hole, or by material from the dust
