Year: 2026
Type: article
Abstract: The spectra of exoplanet atmospheres are affected by aerosols (clouds and hazes) of uncertain origin. Proposed aerosol formation mechanisms include gas condensation or photochemical reactions. We measured the transmission spectrum of the tidally locked gas giant exoplanet WASP-94A b and identified asymmetry in its atmosphere. The morning limb is cooler and cloudy, whereas the evening limb is hotter and exhibits gaseous water absorption features. We interpret this difference as being due to the formation of cloud droplets near the morning limb, which evaporate during circulation to the evening limb. The dominant aerosols are clouds cycling between the day and night sides of the atmosphere, not photochemical hazes. The resulting asymmetry can severely bias chemical abundance measurements, unless limb-resolved spectroscopy is available.
Source: Science
Authors: Sagnick Mukherjee, David K. Sing, Guangwei Fu, Kevin B. Stevenson, Stephen P. Schmidt, Harry Baskett, Mei Ting Mak, Patrick McCreery, Natalie H. Allen, Katherine A. Bennett, Duncan A. Christie, Carlos Gascón, Jayesh Goyal, Éric Hébrard, Joshua D. Lothringer, Mercedes López-Morales, Jacob Lustig-Yaeger, Erin M. May, L. C. Mayorga, Nathan Mayne, Lakeisha M. Ramos Rosado, Henrique Reggiani, Zafar Rustamkulov, Kevin C. Schlaufman, Kristin S. Sotzen, Daniel Thorngren, Le-Chris Wang, Maria Zamyatina
Institutions: Johns Hopkins University, University of California, Santa Cruz, Arizona State University, Johns Hopkins University Applied Physics Laboratory, University of Exeter, University of Oxford, Max Planck Institute for Astronomy, Smithsonian Institution, Harvard University, Institut d'Estudis Espacials de Catalunya, Center for Astrophysics Harvard & Smithsonian, National Institute of Science Education and Research, Homi Bhabha National Institute, Space Telescope Science Institute
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
Awards: TEX Fellowship: Understanding Exoplanet Atmospheres with JWST, G5762276426, Graduate Research Fellowship Program (GRFP), A spectroscopic map of Ultra-Hot Jupiter WASP-121b using JWST (Astronomy Theory), MRI: Acquisition of a High Performance Computer for Computational Science at UC Santa Cruz
OpenAlex ID: W4416139311