Ground-based detection of an extended helium atmosphere in the Saturn-mass exoplanet WASP-69b

Nortmann, L.; Pallé, E.; Salz, Michael; Sanz-Forcada, Jorge; Nagel, Evangelos; Alonso-Floriano, F. Javier; Czesla, Stefan; Yan, Fei; Chen, G.; Snellen, Ignas A. G.; Zechmeister, Mathias; Schmitt, Jürgen H. M. M.; López-Puertas, Manuel; Casasayas-Barris, N.; Bauer, Florian F.; Amado, Pedro J.; Caballero, José A.; Dreizler, Stefan; Henning, Thomas; Lampón, Manuel; Montes, David; Molaverdikhani, Karan; Quirrenbach, Andreas; Reiners, Ansgar; Ribas, Ignasi; Sánchez-López, Alejandro; Schneider, P. Christian; Zapatero Osorio, María R.
Bibliographical reference

Science, Volume 362, Issue 6421, pp. 1388-1391 (2018).

Advertised on:
12
2018
Journal
Number of authors
28
IAC number of authors
4
Citations
184
Refereed citations
162
Description
Hot gas giant exoplanets can lose part of their atmosphere due to strong stellar irradiation, and these losses can affect their physical and chemical evolution. Studies of atmospheric escape from exoplanets have mostly relied on space-based observations of the hydrogen Lyman-α line in the far ultraviolet region, which is strongly affected by interstellar absorption. Using ground-based high-resolution spectroscopy, we detected excess absorption in the helium triplet at 1083 nanometers during the transit of the Saturn-mass exoplanet WASP-69b, at a signal-to-noise ratio of 18. We measured line blueshifts of several kilometers per second and posttransit absorption, which we interpret as the escape of part of the atmosphere trailing behind the planet in comet-like form.
Related projects
Projects' name image
Exoplanets and Astrobiology

The search for life in the universe has been driven by recent discoveries of planets around other stars (known as exoplanets), becoming one of the most active fields in modern astrophysics. The growing number of new exoplanets discovered in recent years and the recent advance on the study of their atmospheres are not only providing new valuable

Enric
Pallé Bago