Artist's conception of the clouds flowing out from the center of the Milky Way, entrained in a very hot wind that has accelerated them to velocities of many hundreds of kilometers per second. Most of the clouds have been detected by the Green Bank Telescope through their radio emission from hydrogen, but a few (indicated in blue) are now known to contain molecular gas as well. The clouds were blasted out of the Milky by processes associated with star formation or the central black hole.