A combined transmission spectrum of the Earth-sized exoplanets TRAPPIST-1 b and c

  title={A combined transmission spectrum of the Earth-sized exoplanets TRAPPIST-1 b and c},
  author={Julien de Wit and Hannah R. Wakeford and Micha{\"e}l Gillon and Nikole K. Lewis and Jeff A. Valenti and B-O. Demory and Adam J. Burgasser and Artem Burdanov and Laetitia Delrez and Emmanuel Jehin and Susan M. Lederer and Didier Queloz and Amaury H. M. J. Triaud and Val{\'e}rie Van Grootel},
Three Earth-sized exoplanets were recently discovered close to the habitable zone of the nearby ultracool dwarf star TRAPPIST-1 (ref. 3). The nature of these planets has yet to be determined, as their masses remain unmeasured and no observational constraint is available for the planetary population surrounding ultracool dwarfs, of which the TRAPPIST-1 planets are the first transiting example. Theoretical predictions span the entire atmospheric range, from depleted to extended hydrogen-dominated… 
Atmospheric reconnaissance of the habitable-zone Earth-sized planets orbiting TRAPPIST-1
Seven temperate Earth-sized exoplanets readily amenable for atmospheric studies transit the nearby ultracool dwarf star TRAPPIST-1 (refs 1,2). Their atmospheric regime is unknown and could range from
Reconnaissance of the TRAPPIST-1 exoplanet system in the Lyman-α line
The TRAPPIST-1 system offers the opportunity to characterize terrestrial, potentially habitable planets orbiting a nearby ultracool dwarf star. We performed a four-orbit reconnaissance with the Space
Temporal Evolution of the High-energy Irradiation and Water Content of TRAPPIST-1 Exoplanets
The ultracool dwarf star TRAPPIST-1 hosts seven Earth-size transiting planets, some of which could harbor liquid water on their surfaces. Ultraviolet observations are essential to measuring their
Atmospheric escape from the TRAPPIST-1 planets and implications for habitability
The atmospheric escape rates numerically and analytically for the planets of the TRAPPIST-1 system are determined and it is shown that the outer planets are potentially likely to retain their atmospheres over billion-year timescales.
Ground-based Optical Transmission Spectroscopy of the Small, Rocky Exoplanet GJ 1132b
Terrestrial Solar System planets either have high mean molecular weight atmospheres, as with Venus, Mars, and Earth, or no atmosphere at all, as with Mercury. We do not have sufficient observational
The nature of the TRAPPIST-1 exoplanets.
Context. The TRAPPIST-1 system hosts seven Earth-sized, temperate exoplanets orbiting an ultra-cool dwarf star. As such, it represents a remarkable setting to study the formation and evolution of
Do the TRAPPIST-1 Planets Have Hydrogen-rich Atmospheres?
Recently, transmission spectroscopy in the atmospheres of the TRAPPIST-1 planets revealed flat and featureless absorption spectra, which rule out cloud-free hydrogen-dominated atmospheres.
The 0.8–4.5 μm Broadband Transmission Spectra of TRAPPIST-1 Planets
The TRAPPIST-1 planetary system represents an exceptional opportunity for the atmospheric characterization of temperate terrestrial exoplanets with the upcoming James Webb Space Telescope (JWST).
A Review of Possible Planetary Atmospheres in the TRAPPIST-1 System
It is shown that (i) Hubble Space Telescope transit observations, (ii) bulk density measurements comparison with H2-rich planets mass-radius relationships, (iii) atmospheric escape modelling, and (iv) gas accretion modelling altogether offer solid evidence against the presence of hydrogen-dominated—cloud-free and cloudy—atmospheres around TRAPPIST-1 planets.
Polarization of Trappist-1 by the Transit of Its Planets
  • S. Sengupta
  • Physics, Geology
    The Astrophysical Journal
  • 2018
As the first and till date the only one multiple planet hosting dwarf star that is sufficiently cool to form condensate cloud in it atmosphere, Trappist-1 provides unique opportunity to test the


A ground-based transmission spectrum of the super-Earth exoplanet GJ 1214b
A ground-based measurement of the transmission spectrum of GJ 1214b between wavelengths of 780 and 1,000 nm is reported, finding the lack of features in this spectrum rules out cloud-free atmospheres composed primarily of hydrogen.
Clouds in the atmosphere of the super-Earth exoplanet GJ 1214b
A measurement of the transmission spectrum of GJ 1214b at near-infrared wavelengths is reported, sufficiently precise to detect absorption features from a high mean-molecular-mass atmosphere and rule out cloud-free atmospheric models with compositions dominated by water, methane, carbon monoxide, nitrogen or carbon dioxide.
Capitalizing on the observational advantage oered by its tiny M dwarf host, we present HST/WFC3 grism measurements of the transmission spectrum of the super-Earth exoplanet GJ1214b. These are the rst
Transmission spectrum of Venus as a transiting exoplanet
On 5-6 June 2012, Venus will be transiting the Sun for the last time before 2117. This event is an unique opportunity to assess the feasibility of the atmospheric characterisation of Earth-size
Hubble Space Telescope Near-IR Transmission Spectroscopy of the Super-Earth HD 97658b
Recent results from the Kepler mission indicate that super-Earths (planets with masses between 1 10 times that of the Earth) are the most common kind of planet around nearby Sun-like stars. These
Direct Measure of Radiative and Dynamical Properties of an Exoplanet Atmosphere
Two decades after the discovery of 51 Peg b, the formation processes and atmospheres of short-period gas giants remain poorly understood. Observations of eccentric systems provide key insights on
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.
Constraining Exoplanet Mass from Transmission Spectroscopy
This paper presents a method to extract an exoplanet’s mass solely from its transmission spectrum and finds good agreement between the mass retrieved for the hot Jupiter HD 189733b from transmission spectroscopy with that from RV measurements.
Habitability of terrestrial-mass planets in the HZ of M Dwarfs – I. H/He-dominated atmospheres
The ubiquity of M dwarfs, combined with the relative ease of detecting terrestrial-mass planets around them, has made them prime targets for finding and characterising planets in the "Habitable Zone"
We explore the minimum distance from a host star where an exoplanet could potentially be habitable in order not to discard close-in rocky exoplanets for follow-up observations. We find that the inner