Astronomy Picture of the Day Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer. 2003 April 4 Clusters and Nebulae of the Hexagon Credit & Copyright: Axel Mellinger Explanation: At first, the bright stars of the large asterism known as the (northern) Winter Hexagon might be hard to pick out in this gorgeous deep sky mosaic from December 2002. But placing your cursor over the picture will reveal the hexagon's outlines and the bright clusters and nebulae along a stunning portion of...