Titanium oxide and chemical inhomogeneity in the atmosphere of the exoplanet WASP-189b

Title	Titanium oxide and chemical inhomogeneity in the atmosphere of the exoplanet WASP-189b
Authors	Bibiana Prinoth, H. Jens Hoeijmakers, Daniel Kitzmann, Elin Sandvik, Julia V. Seidel, Monika Lendl, Nicholas W. Borsato, Brian Thorsbro, David R. Anderson, David Barrado, Kateryna Kravchenko, Romain Allart, Vincent Bourrier, Heather M. Cegla, David Ehrenreich, Chloe Fisher, Christophe Lovis, Andrea Guzmán-Mesa, Simon Grimm, Matthew Hooton, Brett M. Morris, Maria Oreshenko, Lorenzo Pino, Kevin Heng
Magazine	N/A
Date	11/24/2021
Introduction	Atmospheric temperatures typically decline with altitude unless a shortwave absorber creates a temperature inversion, a role ozone fulfills on Earth. For highly irradiated exoplanets, titanium oxide (TiO) and vanadium oxide (VO) are theorised to act as such absorbers. While previous observations of TiO and VO have yielded inconsistent results, this study presents a clear identification of TiO in the ultra-hot Jupiter WASP-189b through high-resolution transmission spectroscopy. This identification utilised a cross-correlation technique applied to numerous TiO spectral lines spanning 460 to 690 nm. Furthermore, we report the presence of various metals, including neutral and ionised iron and titanium, along with chromium, magnesium, vanadium, and manganese. Differences in the spectral line positions for these species suggest spatial variations in their chemical compositions, indicating their presence in distinct atmospheric regions or dynamic states. This provides direct observational support for the three-dimensional thermo-chemical layering within an exoplanet's atmosphere, obtained via high-resolution ground-based spectroscopy.
Quote	Bibiana Prinoth, H. Jens Hoeijmakers and Daniel Kitzmann et al. Titanium oxide and chemical inhomogeneity in the atmosphere of the exoplanet WASP-189b. 2021.
Element	Chromium (Cr) , Magnesium (Mg) , Manganese (Mn) , Titanium (Ti) , Vanadium (V)
Industry	Research & Laboratory , Space