Water in the Universe: water on exoplanets

Exoplanet atmosphere

Artistic impression of a star seen through the atmosphere of a planet orbiting it. Credits: NASA/Goddard Space Flight Center

Astronomers have already confirmed more than 2000 planets orbiting other stars. In some of the larger planets, similar to Jupiter, water vapour was detected in their atmospheres. For smaller planets, this detection is more difficult.

If in a rocky planet, similar to Earth in size, we can confirm the presence of water vapour in its atmosphere, there might also be liquid water on its surface provided that the planet is at a suitable distance from the parent star. We can thus expect that appropriate conditions for the development of life as we know it may exist there.

Astronomers have already confirmed more than 2000 planets orbiting other stars. In some of the larger planets, similar to Jupiter, water vapour was detected in their atmospheres. For smaller planets, this detection is more difficult.

NASA’s James Webb Space Telescope, which is scheduled to launch in 2018, will enable the search for signs of water vapour and other molecules in the atmosphere of exoplanets with only a few times the mass of the Earth.