Scientists say they have found evidence of water on five planets outside our solar system; WASP-17b, HD209458b, WASP-12b, WASP-19b and XO-1b.. They have been using the Hubble Space Telescope, to study these planets they call “hot Jupiters,” they are massive worlds that orbit close to their stars.
Nasa writes in a press release that the presence of atmospheric water was reported previously on a few exoplanets orbiting stars beyond our solar system, but this is the first study to conclusively measure and compare the profiles and intensities of these signatures on multiple worlds.
The study has been published in Astrophysical Journal, see more information and reference. The below video explains how scientists can go about finding out what planets and their atmospheres consists of.
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