Picture of the day - March 22, 2005

The Horsehead Nebula

Photo courtesy of NASA  Today's photo features one of the most identifiable nebulae in the heavens: the Horsehead Nebula. A quick look at the center of the red area will explain the unusual name. The Horsehead Nebula was discovered in 1888 by Williamina Paton Fleming while examining a dry plate (a then new advancement in photography) of an area of the constellation Orion. The near-by star Sigma Orionis ionizes a cloud of hydrogen gas located behind the nebula, creating the beautiful red glow. The dark area forming the horsehead is actually a cloud of dust. The Horsehead Nebula is 1,500 light years away from the earth, meaning it is so far away from us that the light we see when we view it with a telescope took 1,500 years to reach us after it left the nebula! One of the most photographed objects in space, images of the Horsehead Nebula have been seen by millions of people world-wide.   Picture Of The Day Homepage Interesting Articles