Exotic cocktail in the atmosphere of an extreme exoplanet

January 28, 2022

(News from Nanowerk) Using high-resolution spectroscopy, researchers at Lund University in Sweden have succeeded in mapping the atmosphere of an exoplanet located 322 light years from Earth. The knowledge gained about the hot gases surrounding the Jupiter-like planet is important for understanding Earth-like planets.

WASP-189b is a planet outside our own solar system, with a daytime temperature of 3,200 degrees Celsius. The planet is very close to its host star, with a year lasting 2.7 days, the time it takes the planet to orbit the star. WASP-189b is perhaps the most extreme of approximately 4,300 exoplanets – planets in solar systems other than our own – that have been confirmed so far.

Since it was observed in 2020 by the CHEOPS satellite, it has aroused the interest of astronomers. In a new study published in natural astronomy (“Titanium oxide and chemical inhomogeneity in the atmosphere of exoplanet WASP-189 b”), new facts emerge about the fiery gas giant.

“We used a high-resolution spectrograph to collect light from the host star, at a time when the light also passed through the gaseous envelope of the exoplanet. After extracting the relevant parts of the spectrum, we were able to relate at least nine known substance variants to the atmosphere of WASP-189b,” says Bibiana Prinoth, a PhD student in astronomy at Lund University who led the study.

The major discovery is that the atmosphere of WASP-189b contains titanium oxide, which until now could not be detected with certainty in the atmosphere of an ultra-hot gas giant. In addition to titanium oxide, the researchers found the following elements: iron, titanium, chromium, vanadium, magnesium and manganese.

But that is not the only thing that stands out: by studying the so-called positions of the lines of each element in the atmosphere, the researchers were able to observe that these varied. This showed that WASP-189b has a type of layered atmosphere where three-dimensional chemistry, thermal effects and dynamics in the form of winds play an important role.

“In the past, it was only possible to analyze the atmospheres of this type of exoplanet with one-dimensional models. In our study, we are paving the way for the use of high-resolution spectrographs to gain a much deeper understanding of exoplanet atmospheres,” says Bibiana Prinoth.

The characterization of the atmosphere of exoplanets has become an important area of ​​research in astronomy and astrophysics. Now that the technical tools are in place, it will be possible for scientists to compare in detail the chemical composition of different types of exoplanet atmospheres, even when dealing with cooler celestial bodies that more closely resemble our own. planet.

“I am often asked if I think my research is relevant to the search for life elsewhere in the universe. My answer is always yes. This type of study is a first step in this research,” concludes Bibiana Prinoth.

Comments are closed.