Astronomy Picture of the Day

Explanation: Cradled in cosmic dust and glowing hydrogen, stellar nurseries in Orion the Hunter lie at the edge of giant molecular clouds some 1,500 light-years away. Spanning about 30 degrees, this breath-taking vista stretches across the well-known constellation from head to toe (left to right) and beyond. At 1,500 light years away, the Great Orion Nebula is the closest large star forming region, here visible just right and below center. To its left are the Horsehead Nebula, M78, and Orion's belt stars. Sliding your cursor over the picture will also find red giant Betelgeuse at the hunter's shoulder, bright blue Rigel at his foot, the Witch Head Nebula above -- and illuminated by -- Rigel, and the glowing Lambda Orionis (Meissa) nebula on the left, near Orion's head. Of course, the Orion Nebula and bright stars are easy to see with the unaided eye, but dust clouds and emission from the extensive interstellar gas in this nebula-rich complex, are too faint and much harder to record. In this mosaic of broadband telescopic images, additional image data acquired with a narrow hydrogen alpha filter was used to bring out the pervasive tendrils of energized atomic hydrogen gas like in the arc of the giant Barnard's Loop.