JWST Early Release Science: Transiting Exoplanets

Transmission spectroscopy observations from the James Webb Space Telescope show the detection of carbon dioxide in the atmosphere of the gas giant exoplanet WASP-39b.

Time-series observations from the JWST of the transiting exoplanet WASP-39b show gaseous water in the planet’s atmosphere and place an upper limit on the abundance of methane.

The transmission spectrum of the exoplanet WASP-39b is obtained using observations from the Single-Object Slitless Spectroscopy mode of the Near Infrared Imager and Slitless Spectrograph instrument aboard the JWST.

The medium-resolution transmission spectrum of the exoplanet WASP-39b, described using observations from the Near Infrared Spectrograph G395H grating aboard JWST, shows significant absorption from CO₂ and H₂O and detection of SO₂.

A broad-wavelength 0.5–5.5 µm atmospheric transmission spectrum of WASP-39b, a 1,200 K, roughly Saturn-mass, Jupiter-radius exoplanet, demonstrates JWST’s sensitivity to a rich diversity of exoplanet compositions and chemical processes.

Observations from the JWST show the presence of a spectral absorption feature at 4.05 μm arising from SO₂ in the atmosphere of the gas giant exoplanet WASP-39b, which is produced by photochemical processes and verified by numerical models.

The dayside thermal emission spectrum and brightness temperature map of the ultra-hot Jupiter WASP-18b obtained from the NIRISS instrument on the JWST showed water emission features, an atmosphere consistent with solar metallicity, as well as a steep and symmetrical decrease in temperature towards the nightside.

Observations from the JWST MIRI/LRS show the detection of SO₂ spectral features in the 5–12-μm transmission spectrum of the hot, Saturn-mass exoplanet WASP-39b, suggesting that photochemistry is a key process in high-temperature exoplanet atmospheres.

Phase-resolved mid-infrared observations from JWST of the hot gas giant WASP-43b detect a day–night difference of 659 ± 19 K. Comparison with climate models shows that the observations are compatible with cloudy skies, at least on the nightside, and the lack of methane detection suggests the presence of disequilibrium chemistry.

A combined analysis of datasets across four JWST instrument modes provides a benchmark transmission spectrum for the Saturn-mass WASP-39 b. The broad wavelength range and high resolution constrain orbital and stellar parameters to below 1%.

The atmospheric terminator region of WASP-39 b, a hot gas giant exoplanet, is inhomogeneous, despite past assumptions, with the evening terminator being hotter and thus probably clearer, and the morning terminator probably being cloudy and consequently cooler.

An unprecedented glimpse of a distant planet reveals clues about how it might have formed. Scientists explain why it’s a win for atmospheric chemistry, and celebrate the technology that made it possible.

Ground-breaking observations by the James Webb Space Telescope reveal clouds and chemical reactions on a world outside our Solar System.

Phase-curve observations of the ‘hot Jupiter’ exoplanet WASP-43b, made at mid-infrared wavelengths using JWST, provide evidence that fast winds limit the formation of methane on the cooler, cloudy nightside of the planet.

Astronomers Natalie Batalha and Natasha Batalha collaborate to understand the variety of planets outside our Solar System.

Benchmark testing of many opacity models of exoplanetary transmission spectra, simulating representative spectra to be obtained with the James Webb Space Telescope, highlights the presence of biases that would significantly reduce the accuracy on the retrieval of atmospheric parameters. Mitigation strategies are presented.

The dayside thermal emission spectrum and brightness temperature map of the ultra-hot Jupiter WASP-18b obtained from the NIRISS instrument on the JWST showed water emission features, an atmosphere consistent with solar metallicity, as well as a steep and symmetrical decrease in temperature towards the nightside.

Transmission and emission spectra of the 825 K warm Jupiter WASP-80b taken with the NIRCam instrument of the JWST show strong evidence of CH₄ at greater than 6σ significance

Evidence of a large temperature difference between dawn and dusk has been observed on the exoplanet WASP-107 b. This planet is so cool that it was not expected to exhibit this phenomenon, implying a need to further explore the exoplanet population.