Earth-like extrasolar planet. Artwork of an Earth- like planet (centre) seen from orbit around one of its moons. Two other moons,the planet's Sun-like star,the Milky Way,and several galaxies are also seen. An alien (or extrasolar) planet has to fit a narrow range of sizes and distances from its star if it is to have a surface temperature suitable for liquid water,and to retain an atmosphere. The number of other habitable planets in the Milky Way galaxy is not known,but has been estimated at anything between 1 (just Earth) and as many as 10 billion. Many planets have already been discovered orbiting nearby stars | |
Licence : | Droits gérés |
Crédit: | Science Photo Library / Van Ravenswaay, Detlev |
Taille de l’image : | 5906 px × 3543 px |
Model Release : | Non requis |
Property Release : | Non requis |
Restrictions : | - |