WASP-189b is a hot Jupiter in a star system more than 300 light-years away from Earth. It’s twenty times closer to its star than we are to the Sun, and daytime temperatures can soar up to 3,200 degrees Celsius. And since everyone wants to understand exoplanet atmospheres now, and JWST still isn’t collecting data, yet, researchers turned to the HARPS spectrograph in Chile to analyze this planet.

Lead author of a new study in Nature Astronomy, Bibiana Prinoth, explains: We measured the light coming from the planet’s host star and passing through the planet’s atmosphere. The gases in its atmosphere absorb some of the starlight, similar to Ozone absorbing some of the sunlight in Earth’s atmosphere, and thereby leave their characteristic ‘fingerprint’. With the help of HARPS, we were able to identify the corresponding substances.

And they found titanium oxide, which is kind of a wild result, but it could play a similar role to our own ozone layer, blocking some of the stellar radiation. Just as interesting, they found that the fingerprints of the gases were slightly altered in different ways, which could indicate the existence of atmospheric layers, similar to what we have here on Earth except for being Jupiter-like.

This study will help the next studies change from looking at exoplanetary atmospheres as a single, uniform layer to a more complicated structure.

More Information

University of Bern press release

“Titanium oxide and chemical inhomogeneity in the atmosphere of the exoplanet WASP-189 b,” Bibiana Prinoth et al., 2022 January 27, Nature Astronomy