Category: astronomia

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Water-World Exoplanet

An ocean planet, ocean world, water world, aquaplanet or panthalassic planet is a type of terrestrial planet that contains a substantial amount of water either at its surface or subsurface.

Earth is the only astronomical object known to have bodies of liquid water on its surface, although several exoplanets have been found with the right conditions to support liquid water. For exoplanets, current technology cannot directly observe liquid surface water, so atmospheric water vapor may be used as a proxy. The characteristics of ocean worlds—or ocean planets—provide clues to their history, and the formation and evolution of the Solar System as a whole. Of additional interest is their potential to originate and host life.

Water worlds are of extreme interest to astrobiologists for their potential to develop life and sustain biological activity over geological timescales. The five best established water worlds in the Solar System include Europa, Enceladus, Ganymede, and Callisto. A host of other bodies in the outer Solar System are inferred by a single type of observation or by theoretical modeling to have subsurface oceans, and these include: Dione, Pluto, Triton, and Ceres, as well as Mimas, Eris, and Oberon. read more

Lynds Dark Nebula 1251

Image Credit: Francesco Sferlazza, Franco Sgueglia, Astro Brallo

Venus and Jupiter setting over south west London on 1st July 2015

Image credit:

Roger Hutchinson

NGC 1055

Image credit:

Roger Hutchinson

Night Sky

Image credit: Kubo Takaho