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Joined 2026-09-21 Message
Incoming links: David Charbonneau
David Charbonneau 2026-11-05
David Charbonneau detected atmospheric absorption in a transiting exoplanet by comparing the transit depth in different wavelength bands. His team's observations of HD 209458 b found extra dimming near the sodium resonance lines relative to adjacent spectral bands.
During an exoplanet transit, a small fraction of the stellar light passes through the planetary limb. Absorbing atmospheric gas therefore changes the apparent blocking area with wavelength. The observed feature was weaker than a particular cloud-free model predicted, illustrating why detecting an atmospheric species and uniquely determining the atmospheric structure are different inference problems.[ref]
Detection of an Extrasolar Planet Atmosphere by David Charbonneau and others. Abstract: four transits, differential sodium absorption and possible explanations of reduced amplitude
Portrait of David Charbonneau
. NASA/Spitzer Space Telescope portrait published in 2005; public-domain image record on Wikimedia Commons. Source.