![astronomers-detect-hydroxyl-molecule-signature-in-an-exoplanet-atmosphere](https://utterbuzz.com/wp-content/uploads/2021/05/astronomers-detect-hydroxyl-molecule-signature-in-an-exoplanet-atmosphere-1-640x461.jpg)
Astronomers have detected a new chemical signature in the atmosphere of an extrasolar planet (a planet that orbits a star other than our Sun). The hydroxyl radical (OH) was found on the dayside of the exoplanet WASP-33b — a so-called ‘ultra-hot Jupiter’, a gas-giant planet orbiting its host star much closer than Mercury orbits the Sun and therefore reaching atmospheric temperatures of more than 2,500° C.