Published December 2, 2022 | Version v2
Dataset Open

Products and Models for "Early Release Science of the Exoplanet WASP-39b with JWST NIRISS"

  • 1. University of Chicago
  • 2. Université de Montréal
  • 3. Arizona State University
  • 4. University of Colorado, Boulder
  • 5. University of California, Santa Cruz
  • 6. Space Telescope Science Institute
  • 7. Johns Hopkins University
  • 8. University College London
  • 9. Osservatorio Astrofisico di Arcetri
  • 10. Earth and Planets Laboratory, Carnegie Institution for Science, Washington, DC, USA

Description

Associated Publication: https://www.nature.com/articles/s41586-022-05674-1

 

Transmission spectroscopy provides insight into the atmospheric properties and consequently the formation history, physics, and chemistry of transiting exoplanets. However, obtaining precise inferences of atmospheric properties from transmission spectra requires simultaneously measuring the strength and shape of multiple spectral absorption features from a wide range of chemical species. This has been challenging given the precision and wavelength coverage of previous observatories. Here, we present the transmission spectrum of the Saturn-mass exoplanet WASP-39b obtained using the SOSS mode of the NIRISS instrument on the JWST. This spectrum spans 0.6−2.8μm in wavelength and reveals multiple water absorption bands, the potassium resonance doublet, as well as signatures of clouds. The precision and broad wavelength coverage of NIRISS-SOSS allows us to break model degeneracies between cloud properties and the atmospheric composition of WASP-39b, favoring a heavy element enhancement ("metallicity") of ∼10−30× the solar value, a sub-solar carbon-to-oxygen (C/O) ratio, and a solar-to-super-solar potassium-to-oxygen (K/O) ratio. The observations are best explained by wavelength-dependent, non-gray clouds with inhomogeneous coverage of the planet's terminator.

Notes

See associated publication: https://www.nature.com/articles/s41586-022-05674-1

Files

zenodo_upload.zip

Files (137.7 MB)

Name Size Download all
md5:447a3085df86591a73476bdf01b16194
137.7 MB Preview Download

Additional details

Related works

Is published in
Journal article: https://arxiv.org/abs/2211.10493 (URL)