Vertical structure of an exoplanet's atmospheric jet stream
Abstract
Ultra-hot Jupiters, an extreme class of planets not found in our solar system, provide a unique window into atmospheric processes. The extreme temperature contrasts between their day- and night-sides pose a fundamental climate puzzle: how is energy distributed? To address this, we must observe the 3D structure of these atmospheres, particularly their vertical circulation patterns, which can serve as a testbed for advanced Global Circulation Models (GCM) [e.g. 1]. Here, we show a dramatic shift in atmospheric circulation in an ultra-hot Jupiter: a unilateral flow from the hot star-facing side to the cooler space-facing side of the planet sits below an equatorial super-rotational jet stream. By resolving the vertical structure of atmospheric dynamics, we move beyond integrated global snapshots of the atmosphere, enabling more accurate identification of flow patterns and allowing for a more nuanced comparison to models. Global circulation models based on first principles struggle to replicate the observed circulation pattern [3], underscoring a critical gap between theoretical understanding of atmospheric flows and observational evidence. This work serves as a testbed to develop more comprehensive models applicable beyond our Solar System as we prepare for the next generation of giant telescopes.
Keywords
Cite
@article{arxiv.2502.12261,
title = {Vertical structure of an exoplanet's atmospheric jet stream},
author = {Julia V. Seidel and Bibiana Prinoth and Lorenzo Pino and Leonardo A. dos Santos and Hritam Chakraborty and Vivien Parmentier and Elyar Sedaghati and Joost P. Wardenier and Casper Farret Jentink and Maria Rosa Zapatero Osorio and Romain Allart and David Ehrenreich and Monika Lendl and Giulia Roccetti and Yuri Damasceno and Vincent Bourrier and Jorge Lillo-Box and H. Jens Hoeijmakers and Enric Pallé and Nuno Santos and Alejandro Suárez Mascareño and Sergio G. Sousa and Hugo M. Tabernero and Francesco A. Pepe},
journal= {arXiv preprint arXiv:2502.12261},
year = {2025}
}
Comments
Accepted for publication in Nature on 16th January 2025, published with DOI 10.1038/s41586-025-08664-1, 5 main figures, 12 main pages plus methods. This work has a companion paper on the same dataset: Prinoth et al. 2025, A&A, DOI: 10.1051/0004-6361/202452405