This composite image shows the size and location of the Smith Cloud on the sky. The cloud appears in false-color, radio wavelengths as observed by the Robert C. Byrd Green Bank Telescope in West Virginia. The visible-light image of the background star field shows the cloud's location in the direction of the summer constellation Aquila. The cloud is 15 degrees across in angular size – the width of an outstretched hand at arm's length. The apparent size of the full moon is added for comparison.
Image Credit: B. Saxton and F. Lockman (NRAO/AUI/NSF), and A. Mellinger