Search Publications
A population of red candidate massive galaxies 600 Myr after the Big Bang
Labbé, Ivo; van Dokkum, Pieter; Bezanson, Rachel +8 more
Galaxies with stellar masses as high as roughly 1011 solar masses have been identified1-3 out to redshifts z of roughly 6, around 1 billion years after the Big Bang. It has been difficult to find massive galaxies at even earlier times, as the Balmer break region, which is needed for accurate mass estimates, is redshifted to w…
Confirmation and refutation of very luminous galaxies in the early Universe
Papovich, Casey; Finkelstein, Steven L.; Buat, Véronique +34 more
During the first 500 million years of cosmic history, the first stars and galaxies formed, seeding the Universe with heavy elements and eventually reionizing the intergalactic medium1-3. Observations with the James Webb Space Telescope (JWST) have uncovered a surprisingly high abundance of candidates for early star-forming galaxies, wit…
Early Release Science of the exoplanet WASP-39b with JWST NIRSpec PRISM
Zhang, X.; Heng, K.; May, E. M. +91 more
Transmission spectroscopy1-3 of exoplanets has revealed signatures of water vapour, aerosols and alkali metals in a few dozen exoplanet atmospheres4,5. However, these previous inferences with the Hubble and Spitzer Space Telescopes were hindered by the observations' relatively narrow wavelength range and spectral resolving po…
Early Release Science of the exoplanet WASP-39b with JWST NIRSpec G395H
Carter, Aarynn L.; Gibson, Neale P.; Mikal-Evans, Thomas +89 more
Measuring the abundances of carbon and oxygen in exoplanet atmospheres is considered a crucial avenue for unlocking the formation and evolution of exoplanetary systems1,2. Access to the chemical inventory of an exoplanet requires high-precision observations, often inferred from individual molecular detections with low-resolution space-b…
Identification of carbon dioxide in an exoplanet atmosphere
Henning, Thomas; Fortney, Jonathan J.; Carter, Aarynn L. +129 more
Carbon dioxide (CO2) is a key chemical species that is found in a wide range of planetary atmospheres. In the context of exoplanets, CO2 is an indicator of the metal enrichment (that is, elements heavier than helium, also called `metallicity')1-3, and thus the formation processes of the primary atmospheres of hot g…
Photochemically produced SO2 in the atmosphere of WASP-39b
Henning, Thomas; Fortney, Jonathan J.; Carter, Aarynn L. +82 more
Photochemistry is a fundamental process of planetary atmospheres that regulates the atmospheric composition and stability1. However, no unambiguous photochemical products have been detected in exoplanet atmospheres so far. Recent observations from the JWST Transiting Exoplanet Community Early Release Science Program2,3 found …
A massive quiescent galaxy at redshift 4.658
Wild, Vivienne; Dunlop, James S.; Cullen, Fergus +10 more
The extremely rapid assembly of the earliest galaxies during the first billion years of cosmic history is a major challenge for our understanding of galaxy formation physics1-5. The advent of the James Webb Space Telescope (JWST) has exacerbated this issue by confirming the existence of galaxies in substantial numbers as early as the fi…
Early Release Science of the exoplanet WASP-39b with JWST NIRISS
Henning, Thomas; Fortney, Jonathan J.; Carter, Aarynn L. +86 more
The Saturn-mass exoplanet WASP-39b has been the subject of extensive efforts to determine its atmospheric properties using transmission spectroscopy1-4. However, these efforts have been hampered by modelling degeneracies between composition and cloud properties that are caused by limited data quality5-9. Here we present the t…
Thermal emission from the Earth-sized exoplanet TRAPPIST-1 b using JWST
Fortney, Jonathan J.; Bell, Taylor J.; Lagage, Pierre-Olivier +3 more
The TRAPPIST-1 system is remarkable for its seven planets that are similar in size, mass, density and stellar heating to the rocky planets Venus, Earth and Mars in the Solar System1. All the TRAPPIST-1 planets have been observed with transmission spectroscopy using the Hubble or Spitzer space telescopes, but no atmospheric features have…
Early Release Science of the exoplanet WASP-39b with JWST NIRCam
Fortney, Jonathan J.; Carter, Aarynn L.; Gibson, Neale P. +96 more
Measuring the metallicity and carbon-to-oxygen (C/O) ratio in exoplanet atmospheres is a fundamental step towards constraining the dominant chemical processes at work and, if in equilibrium, revealing planet formation histories. Transmission spectroscopy (for example, refs. 1,2) provides the necessary means by constraining the abundance…