Category: star

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

NGC 1055

Image credit:

Roger Hutchinson

Even in their downtime, many astronomers cannot resist catching one more glimpse of the star-studded sky. This image captures a fascinated astronomer stargazing from the Residencia, ESO’s living quarters for staff working at Paranal Observatory in Chile. This view shows the dusty and star-filled band of the Milky Way rising over the Atacama Desert, the remote home of ESO’s Very Large Telescope (which sits atop Cerro Paranal)

Night Sky

Image credit: Kubo Takaho

This image of the Omega Nebula (Messier 17), captured by ESO’s Very Large Telescope (VLT), is one of the sharpest of this object ever taken from the ground. It shows the dusty, rosy central parts of the famous star-forming region in fine detail. Credit: ESO

Arp 274 is a system of three galaxies that appear to be partially overlapping in the image, although they may be at somewhat different distances. The spiral shapes of two of these galaxies appear mostly intact. The third galaxy (far left) is more compact, but shows evidence of star formation.

Two of the three galaxies are forming new stars at a high rate. This is evident in the bright blue knots of star formation that are strung along the arms of the galaxy on the right and along the small galaxy on the left.

Credit: NASA & ESA

Blue Straggler Stars in Globular Cluster M53 

Image Credit: ESA/Hubble, NASA

Against a stunning backdrop of thousands of galaxies, this odd-looking galaxy with the long streamer of stars appears to be racing through space, like a runaway pinwheel firework.

This picture of the galaxy UGC 10214 was taken by the Advanced Camera for Surveys (ACS), which was installed aboard the NASA/ESA Hubble Space Telescope in March (2002) during Servicing Mission 3B. Dubbed the ‘Tadpole’, this spiral galaxy is unlike the textbook images of stately galaxies. Its distorted shape was caused by a small interloper, a very blue, compact, galaxy visible in the upper left corner of the more massive Tadpole. The Tadpole resides about 420 million light-years away in the constellation Draco.

Credit: NASA, Holland Ford (JHU), the ACS Science Team and ESA

Andromeda Galaxy 

Credit: NASA/JPL-Caltech / processed by

Judy Schmidt