Publications by authors named "John Stansberry"
Article Synopsis
- - Charon, Pluto's largest moon, has been studied for its composition and changes caused by radiation, but previous spectral data only covered wavelengths below 2.5 μm, leaving some questions unanswered.
- - Recent observations using JWST have detected carbon dioxide (CO) and hydrogen peroxide (HO) on Charon's northern hemisphere, adding to its known chemical components like water ice and ammonia.
- - The presence of HO suggests active processes affecting the water ice surface, while spectral analysis indicates that CO is mainly found in crystalline form, likely originating from subsurface sources and other processes involving hydrocarbons and solar interactions.
The abundances of main carbon- and oxygen-bearing gases in the atmospheres of giant exoplanets provide insights into atmospheric chemistry and planet formation processes. Thermochemistry suggests that methane (CH) should be the dominant carbon-bearing species below about 1,000 K over a range of plausible atmospheric compositions; this is the case for the solar system planets and has been confirmed in the atmospheres of brown dwarfs and self-luminous, directly imaged exoplanets. However, CH has not yet been definitively detected with space-based spectroscopy in the atmosphere of a transiting exoplanet, but a few detections have been made with ground-based, high-resolution transit spectroscopy including a tentative detection for WASP-80b (ref.
View Article and Find Full Text PDFThe James Webb Space Telescope near-infrared camera (JWST NIRCam) has two 2'. 2 × 2'.2 fields of view that can be observed with either imaging or spectroscopic modes.
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