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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

NGC 1055

Image credit:

Roger Hutchinson

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

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This is the brightest so-called milli-second pulsar known. This old pulsar has been spun up by the accretion of material from a binary companion star as it expands in its red giant phase. The accretion process results in orbital angular momentum of the companion star being converted to rotational angular momentum of the neutron star, which is now rotating about 174 times a second. It spins so fast that the signal sounds like an overactive bumble-bee. This recording has been made with the Parkes radio telescope in Australia. source

This picture, taken by Hubble’s Advanced Camera for Surveys, shows NGC 4696, the largest galaxy in the Centaurus Cluster.

The huge dust lane, around 30 000 light-years across, that sweeps across the face of the galaxy makes NGC 4696 look different from most other elliptical galaxies. Viewed at certain wavelengths, strange thin filaments of ionised hydrogen are visible within it. In this picture, these structures are visible as a subtle marbling effect across the galaxy’s bright centre.

Credit: ESA/Hubble and NASA

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