An intense narrow equatorial jet in Jupiter's lower stratosphere observed by JWST

The atmosphere of Jupiter has east–west zonal jets that alternate with latitude as tracked by cloud motions at tropospheric levels. Above and below the cold tropopause at ~100 mbar, equatorial hazes occur where thermal infrared observations lose sensitivity. James Webb Space Telescope observations of July 2022 reveal these hazes in unprecedented detail and show an intense (~140 m s−1) equatorial jet at ~100–200 mbar, about 70 m s−1 faster than the cloud-top zonal winds, confined to ±3° of the equator and located below stratospheric thermal oscillations spanning at least 0.1–40 mbar that repeat on multiyear cycles. This suggests the new jet is a deep component of Jupiter’s Equatorial Stratospheric Oscillation and may vary in strength over time.

Ricardo Hueso, Agustín Sánchez-Lavega, Thierry Fouchet, Imke de Pater, Arrate Antuñano, Leigh N. Fletcher, Michael H. Wong, Pablo Rodríguez-Ovalle, Lawrence A. Sromovsky, Patrick M. Fry, Glenn S. Orton, Sandrine Guerlet, Patrick G. J. Irwin, Emmanuel Lellouch, Jake Harkett, Katherine de Kleer, Henrik Melin, Vincent Hue, Amy A. Simon, Statia Luszcz-Cook, Kunio M. Sayanagi