K2-18b Exoplanet Water
Despite being much larger than Earth with a radiation environment, an exoplanet called K2-18b had detected water vapor signatures detected for the first time in the atmosphere of a planet beyond our solar system that resides in a habitable zone. NASA’s Hubble Space Telescope found water vapor in the atmosphere of K2-18b, an exoplanet orbiting a small red dwarf star about 110 light-years away in the constellation Leo. Once confirmed, this will be the first and only exoplanet known to have both water in its atmosphere as well as temperatures that could sustain liquid water on a rocky surface. Read more for a video and additional information.



Unfortunately, K2-18b may be more hostile to life as we know it than Earth due to the high level of activity of its red dwarf star exposing the planet to more high-energy radiation. It also has a mass eight times greater than Earth’s, which means its surface gravity would be significantly higher than on our own planet.

“K2-18b is one of hundreds of ‘super-Earths’ — exoplanets with masses between those of Earth and Neptune — found by Kepler. NASA’s TESS mission is expected to detect hundreds more super-Earths in the coming years. The next generation of space telescopes, including the James Webb Space Telescope, will be able to characterize exoplanet atmospheres in more detail,” said NASA in a press release.