Although water vapor has been expected in the atmospheres of nearly all known extrasolar planets, most are too close to their parent star to allow identification.
The identification involving planet HD209458b was made possible since, as seen from Earth, it periodically passes in front of its star. As it does so, its atmosphere blocks a different amount of the starlight at different wavelengths.
An analysis of Hubble data by Harvard University student Heather Knutson made possible a direct comparison to theoretical models developed by Barman. That ultimately led to the identification of water absorption on the planet 150 light-years from Earth.
The research has been accepted for publication in the Astrophysical Journal.
"We now know that water vapor exists in the atmosphere of one extrasolar planet and there is good reason to believe that other extrasolar planets contain water vapor," said Barman.
Although water vapor has been expected in the atmospheres of nearly all known extrasolar planets, most are too close to their parent star to allow identification.
The identification involving planet HD209458b was made possible since, as seen from Earth, it periodically passes in front of its star. As it does so, its atmosphere blocks a different amount of the starlight at different wavelengths.
An analysis of Hubble data by Harvard University student Heather Knutson made possible a direct comparison to theoretical models developed by Barman. That ultimately led to the identification of water absorption on the planet 150 light-years from Earth.
The research has been accepted for publication in the Astrophysical Journal.