Emission nebula (NGC 6357), optical image. Emission nebulae are clouds of gas and dust that are ionised by radiation from hot stars within them, causi

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Emission nebula (NGC 6357), optical image. Emission nebulae are clouds of gas and dust that are ionised by radiation from hot stars within them, causing them to glow. This nebula lies in the constellation Scorpius. The ionising radiation comes from the open cluster Pismis 24, seen as a bright patch within the nebula, which condensed from the gas cloud. Although faint, the nebula is easily located by following the straight line of 4 stars (upper centre).

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Size: 3932px × 2648px
Photo credit: © ROBERT GENDLER/MARTIN PUGH/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: 24, 6357, astronomical, astronomy, astrophysical, astrophysics, birth, clouds, cluster, dust, emission, evolution, formation, gas, hii, hydrogen, ionised, nebula, nebulae, nebulosity, ngc, open, pismis, region, scorpius, space, star, starbirth, stellar, telescope