Water vapor has been discovered in the atmosphere of exoplanet K2-18b. -- Story: Water Vapor Detected in Atmosphere of an Alien World Nearly Twice the Size of Earth: https://www.space.com/water-vapor-in-atmosphere-of-alien-planet-k2-18b.html
The alien world orbits a red dwarf star which has lead to speculation that it is exposed to higher levels of radiation than Earth. In the future, studies using NASA's James Webb Space Telescope and other next generation telescopes could reveal more about the planet.
Directed by: Bethany Downer
Editing: Nico Bartmann.
Web and technical support: Mathias André and Raquel Yumi Shida.
Written by: Bethany Downer & UCL:
Footage and photos: ESA/Hubble, M. Kornmesser, NASA's Goddard Space Flight Center Conceptual Image Lab