Scientists have detected “a strong water signature” in the atmosphere of a distant Neptune sized planet called HAT-P-26b. The study conducted using NASA’s Hubble and Spitzer space telescopes has showed that HAT-P-26b has a primitive atmosphere composed almost entirely of hydrogen and helium. Although the planet is not a water world, its atmosphere which is relatively clear of clouds has a strong water signature.
Researchers have detected the presence of water by pooling data obtained from four transits when the Neptune sized planet passed in front of its host star. By studying how the signatures of the starlight changes, researchers can come up with the chemical composition of the atmosphere. The study has been published in the journal Science. Significance This study is one of the most detailed studies till date conducted in a planet that is roughly the size of the Neptune and close to its star.
The water measured in the planet is one of the best measurement of water to date found on an exoplanet of this size. The HAT-P-26b is located about 437 light years away. The significance of the study lies in the fact that it would help in understanding more about the birth and development of planetary systems. The data obtained will also come handy in estimating the HAT-P-26b’s metallicity, which is an indication of composition of elements heavier than hydrogen and helium. The planet’s metallicity was found to be about 4.8 times that of the Sun. It would help in understanding the planet formation.