APOD
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.
Orion: Belt, Flame, and Horsehead
Explanation: What surrounds the famous belt stars of Orion? A deep exposure shows everything from dark nebula to star clusters, all embedded in an extended patch of gaseous wisps in the greater Orion Molecular Cloud Complex . T h e brightest three stars, appearing diagonally on the left of the featured image are indeed the famous three stars that make up the belt of Orion . Just below Alnitak , the lowest of the three belt stars , is the Flame Nebula , glowing with excited hydrogen gas and immersed in filaments of dark brown dust. Just to the right of Alnitak lies the Horsehead Nebula , a dark indentation of dense dust that has perhaps the most recognized nebular shapes on the sky. The dark molecular cloud , roughly 1,500 light years distant, is cataloged as Barnard 33 and is seen primarily because it is backlit by the nearby massive star Sigma Orionis . The Horsehead Nebula will slowly shift its apparent shape over the next few million years and will eventually be destroyed by the high-energy starlight.
| Date | June 4, 2017 |
|---|---|
| Credit | Image Credit & Copyright: Rogelio Bernal Andreo (Deep Sky Colors) |
| Authors & editors: | Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) |
| A service of: |
ASD at NASA / GSFC, NASA Science Activation & Michigan Tech. U. |



