Orion constellation. Diagram of stars and other objects in the constellation of Orion. North is at top. This is one of the equatorial constellations v

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Orion constellation. Diagram of stars and other objects in the constellation of Orion. North is at top. This is one of the equatorial constellations visible in both hemispheres of Earth. It is easily recognised by the three stars forming a straight line: Orion's belt. Two other objects are labelled here: the star Sirius (lower left), and McNeil's Nebula (centre). This latter object is a variable nebula that was discovered in January 2004. It is variable because the star at its tip varies in brightness. The nebula is the cloud of gas and dust surrounding the star. It is about 1500 light years from Earth. Sirius is the brightest star in the night sky. It is light years from Earth.

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Size: 3132px × 2677px
Photo credit: © JON LOMBERG/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: astronomy, disc, heat, horizon, hot, landscape, man, radiation, red, setting, silhouette, silhouetted, solar, sun, sunset