Early Release Science of the exoplanet WASP-39b with JWST NIRSpec G395H

Abstract Measuring the abundances of carbon and oxygen in exoplanet atmospheres is considered a crucial avenue for unlocking the formation and evolution of exoplanetary systems 1,2 . Access to the chemical inventory of an exoplanet requires high-precision observations, often inferred from individual molecular detections with low-resolution space-based 3–5 and high-resolution ground-based 6–8 facilities. Here we report the medium-resolution ( R ≈ 600) transmission spectrum of an exoplanet atmosphere between 3 and 5 μm covering several absorption features for the Saturn-mass exoplanet WASP-39b (ref. 9 ), obtained with the Near Infrared Spectrograph (NIRSpec) G395H grating of JWST. Our observations achieve 1.46…

• NA
  National Aeronautics and Space Administration

  Awards: 5-03127, NAS 5-03127, JWST-ERS-01366
• ST
  Space Telescope Science Institute

  Awards: 5-03127, NAS 5-03127
• UO
  University of Bristol
• SA
  Science and Technology Facilities Council

  Awards: ST/T004479/1, ST/W507337/1, ST/P000495/1, ST/X001121/1, ST/R003726/1, ST/V000861/1, ST/T000406/1