Cave nebulae (Sh2-155),an emission nebula complex in the constellation Cepheus. North is at top. Emission nebulae (HII regions) are clouds of gas which glow as hydrogen gas they contain is ionised by radiation from hot stars within them. The nebulae are named for the dark protrusions into the northern edge of the nebulae. This may be due to an obscuring dark nebula; gas and dust which blocks out light from behind it | |
Licence : | Droits gérés |
Crédit: | Science Photo Library / Celestial Image Co. |
Taille de l’image : | 2559 px × 2559 px |
Model Release : | Non requis |
Property Release : | Non requis |
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