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Orion Nebula

The nebulae shown here comprise Orion's sword in the constellation of Orion (left is north in the above image). The Orion Nebula (Messier 42) to the right is the brightest diffuse nebula in the sky. Dominated by red light and strewn with dust lanes, this nebula is about 1,500 light-years away and about 40 light-years across. Many of the filamentary structures visible are shock waves—fronts where fast moving material encounters slow moving gas. Located at the edge of a giant molecular cloud complex spanning hundreds of light-years, these nebulae represent only a small, but very visible, fraction of this region's wealth of interstellar material. Within these colorful clouds of Orion, astronomers have identified what appear to be numerous infant solar systems. To see this star birth better, look at a closeup of the center (light portion) of the Orion nebula. The nebula to the left (north) is dominated by the characteristic blue color of interstellar dust reflecting light from hot young stars. The dark regions in this nebula suggest to many the shape of a running man.

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