Astronomy Picture of the Day

Explanation: Do you recognize the belt of Orion in this image? The familiar trio of stars, visible to the unaided eye, can be found across the upper left. Otherwise, the southern part of the constellation Orion has taken on a new look in this unusually deep and wide view First note that the lower left belt star, Alnitak, illuminates the dusty reflection nebula known as M78. Directly below Alnitak, a close inspection will reveal the Horsehead Nebula. Farther right and below is the Orion Nebula, M42, itself visible to the unaided eye. The brightest star in the frame, near the bottom right, is Rigel. A bright blue star, Rigel illuminates the ominously shaped dust patch known as the Witch Head Nebula, visible as the blue reflection nebula near the lower right corner. Finally, appearing as a vast red ring and encompassing the entire region, is Barnard's Loop. Humans could see this entire menagerie, unaided, were their eyes about 10,000 times more sensitive.