Cave nebula (SH2-155), optical image. This nebula is an emission nebula, known as the Cave nebula because of the dark regions on the northern edge. Em

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Cave nebula (SH2-155), optical image. This nebula is an emission nebula, known as the Cave nebula because of the dark regions on the northern edge. Emission nebulae are clouds of hydrogen gas that are ionised by radiation from hot stars within them, causing them to glow. The dark regions may be due to a dark cloud of dust and gas in the foreground obscuring the light behind. The Cave nebula lies in the constellation Cepheus.

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Size: 4958px × 5286px
Photo credit: © DAVIDE DE MARTIN/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: 2-155, absorption, astronomical, astronomy, astrophysical, astrophysics, birth, cave, cepheus, cloud, clouds, complex, dark, dust, emission, evolution, formation, gas, hii, ionised, nebula, nebulae, nebulosity, region, sh2-155, sharpless, silhouette, silhouetted, space, star, starbirth, stellar, telescope