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A continuum from clear to cloudy hot-Jupiter exoplanets without primordial water depletion
The difference between the planetary radius measured at optical and infrared wavelengths is an effective metric for distinguishing different atmosphere types, so that strong water absorption lines are seen in clear-atmosphere planets and the weakest features are associated with clouds and hazes.
An ultrahot gas-giant exoplanet with a stratosphere
A near-infrared thermal spectrum for the ultrahot gas giant WASP-121b, which has an equilibrium temperature of approximately 2,500 kelvin, is reported, implying that a substantial fraction of incident stellar radiation is retained at high altitudes in the atmosphere, possibly by absorbing chemical species such as gaseous vanadium oxide and titanium oxide.
HST hot-Jupiter transmission spectral survey: evidence for aerosols and lack of TiO in the atmosphere of WASP-12b
We present Hubble Space Telescope (HST) optical transmission spectra of the transiting hot-Jupiter WASP-12b, taken with the Space Telescope Imaging Spectrograph instrument. The resulting spectra
Transmission spectral properties of clouds for hot Jupiter exoplanets
Clouds have an important role in the atmospheres of planetary bodies. It is expected that, like all the planetary bodies in our solar system, exoplanet atmospheres will also have substantial cloud
Hubble Space Telescope hot Jupiter transmission spectral survey: a detection of Na and strong optical absorption in HAT-P-1b
We present an optical to near-infrared transmission spectrum of the hot Jupiter HAT-P-1b, based on Hubble Space Telescope observations, covering the spectral regime from 0.29 to 1.027 μm with Space
Helium in the eroding atmosphere of an exoplanet
A detection of helium absorption at 10,833 Å on the exoplanet WASP-107b reveals that its atmosphere is extended and eroding, and demonstrates a new way to study upper exoplanetary atmospheres.
HAT-P-26b: A Neptune-mass exoplanet with a well-constrained heavy element abundance
HAT-P-26b’s atmosphere is primordial and obtained its gaseous envelope late in its disk lifetime, with little contamination from metal-rich planetesimals, according to a detailed atmospheric study of the transiting Neptune-mass exoplanet.
HST hot-Jupiter transmission spectral survey: detection of potassium in WASP-31b along with a cloud deck and Rayleigh scattering
We present Hubble Space Telescope optical and near-IR transmission spectra of the transiting hot-Jupiter WASP-31b. The spectrum covers 0.3–1.7 μm at a resolution R ∼ 70, which we combine with Spitzer
Statistical Characterization of Hot Jupiter Atmospheres Using Spitzer’s Secondary Eclipses
We report 78 secondary eclipse depths for a sample of 36 transiting hot Jupiters observed at 3.6- and 4.5 microns using the Spitzer Space Telescope. Our eclipse results for 27 of these planets are
A combined transmission spectrum of the Earth-sized exoplanets TRAPPIST-1 b and c
Observations of the combined transmission spectrum of the two inner planets during their simultaneous transits on 4 May 2016 rule out cloud-free hydrogen-dominated atmospheres for each planet at ≥10σ levels; TRAPPIST-1 b and c are therefore unlikely to have an extended gas envelope as they occupy a region of parameter space in which high-altitude cloud/haze formation is not expected to be significant for hydrogen- dominated atmospheres.