This radio image shows the eastern side of Sag A, which is believed to be a remnant of a supernova explosion. The shock wave from the blast excavated a bubble of material, leaving a ΓÇ£smallΓÇ¥ circular shell about 32 light years in radius. Also visible here are details of a large structureΓÇö8 arc minutes or 75 light years in diameterΓÇöthat surrounds the eastern portion of Sag A. Two components can be seen: a large ΓÇ£haloΓÇ¥ (in orange, yellow, green, and blue) and the network of protrusions popping up at right angles to the galactic plane.
