Water-Worlds May Be More Common in the Milky Way Than Previously Thought

 According to new research presented by scientists from Harvard University, water may be a major component of exoplanets (planets orbiting other stars) which are between two to four times the size of Earth.
 Of the 4000 confirmed or candidate exoplanets discovered so far, they fall into two size categories: those with a planetary radius averaging around 1.5 Earth radii and those around 2.5 times the radius of the Earth. New analysts from NASA's Kepler Space Telescope and ESA's Gaia satellite suggest that exoplanets with radius 1.5 times that of Earth's tend to be rocky while the other group tend to be water worlds.
 "This is water, but not as commonly found here on Earth", said leader researcher Li Zeng. "Their surface temperature is expected to be in the 200 to 500 degree Celsius range. Their surface may be shrouded in a water-vapor-dominated atmosphere, with a liquid water layer underneath. Moving deeper, one would expect to find this water transforms into high-pressure ices before we reaching the solid rocky core. The beauty of the model is that it explains just how composition relates to the known facts about these planets".
 Li Zeng continued, "Our data indicate that about 35% of all known exoplanets which are bigger than Earth should be water-rich. These water worlds likely formed in similar ways to the giant planet cores (Jupiter, Saturn, Uranus, Neptune) which we find in our own solar system. The newly-launched TESS mission will find many more of them, with the help of ground-based spectroscopic follow-up. The next generation space telescope, the James Webb Space Telescope, will hopefully characterize the atmosphere of some of them. This is an exciting time for those interested in these remote worlds".

Li Zeng continued, "Our data indicate that about 35% of all known exoplanets which are bigger than Earth should be water-rich. These water worlds likely formed in similar ways to the giant planet cores (Jupiter, Saturn, Uranus, Neptune) which we find in our own solar system. The newly-launched TESS mission will find many more of them, with the help of ground-based spectroscopic follow-up. The next generation space telescope, the James Webb Space Telescope, will hopefully characterize the atmosphere of some of them. This is an exciting time for those interested in these remote worlds".

Read more at: https://phys.org/news/2018-08-water-worlds-common-exoplanets-vast-amounts.html#jCp

Li Zeng continued, "Our data indicate that about 35% of all known exoplanets which are bigger than Earth should be water-rich. These water worlds likely formed in similar ways to the giant planet cores (Jupiter, Saturn, Uranus, Neptune) which we find in our own solar system. The newly-launched TESS mission will find many more of them, with the help of ground-based spectroscopic follow-up. The next generation space telescope, the James Webb Space Telescope, will hopefully characterize the atmosphere of some of them. This is an exciting time for those interested in these remote worlds".

Read more at: https://phys.org/news/2018-08-water-worlds-common-exoplanets-vast-amounts.html#jCp

Read more about this fascinating story at: https://phys.org/news/2018-08-water-worlds-common-exoplanets-vast-amounts.html
Or read the full study at: https://goldschmidt.info/2018/abstracts/abstractView?id=2018003836 

Image Credit: NASA