Volcanic satellites tidally venting Na, K, and SO2 in optical and infrared light
Year: 2025
Type: article
Abstract: ABSTRACT Recent infrared spectroscopy from the James Webb Space Telescope (JWST) has spurred analyses of common volcanic gases such as carbon dioxide (CO$_2$), sulphur dioxide (SO$_2$), alongside alkali metals sodium (Na i) and potassium (K i) surrounding the hot Saturn WASP-39 b. We report more than an order-of-magnitude of variability in the density of neutral Na, K, and SO$_2$ between ground-based measurements and JWST, at distinct epochs, hinting at exogenic physical processes similar to those sourcing Io’s extended atmosphere and torus. Tidally heated volcanic satellite simulations sputtering gas into a cloud or toroid orbiting the planet are able to reproduce the probed line-of-sight column density variations. The estimated SO$_2$ flux is consistent with tidal gravitation predictions, with a Na/SO$_2$ ratio far smaller than Io’s. Although stable satellite orbits at this system are known to be ${<}$15.3 h, several high-resolution alkali Doppler shift observations are required to constrain a putative orbit. Due to the Roche limit interior to the planetary photosphere at ${\sim}$8 h, atmosphere–exosphere interactions are expected to be especially important in this system.
Authors: Apurva V Oza, Andrea Gebek, Moritz Meyer zu Westram, Armen Tokadjian, Anthony L Piro, Renyu Hu, Athira Unni, Raghav Chari, Aaron Bello-Arufe, Carl A Schmidt, Amy J Louca, Yamila Miguel, Raissa Estrela, Jeehyun Yang, Mario Damiano, Yasuhiro Hasegawa, Luis Welbanks, Diana Powell, Rishabh Garg, Pulkit Gupta, Yuk L Yung, Rosaly M C Lopes
Institutions: California Institute of Technology, Jet Propulsion Laboratory, Ghent University, University of Bern, Carnegie Institution for Science, Carnegie Observatories, University of California, Santa Cruz, University of California, Irvine, New York University, University of Tennessee at Knoxville, Boston University, Leiden University, Leiden Observatory, Space Research Organisation Netherlands, Arizona State University, University of Chicago, Indian Institute of Technology Indore
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $3,046
Award: G7771892465
OpenAlex ID: W4414510301