Related papers: Enhanced interplanetary panspermia in the TRAPPIST…
The atmospheres of rocky exoplanets are close to being characterized by astronomical observations, in part due to the commissioning of the James Webb Space Telescope. These observations compel us to understand exoplanetary atmospheres, in…
The early start to life naively suggests that abiogenesis is a rapid process on Earth-like planets. However, if evolution typically takes ~4Gyr to produce intelligent life-forms like us, then the limited lifespan of Earth's biosphere…
With more than 260 extrasolar planetary systems discovered to-date, the search for habitable planets has found new grounds. Unlike our solar system, the stars of many of these planets are hosts to eccentric or close-in giant bodies. Several…
If the origin of life is rare and sensitive to the local conditions at the site of its emergence, then, using the principle of mediocrity within a multiverse framework, we may expect to find ourselves in a universe that is better than usual…
Rocky exoplanets orbiting in the habitable zone (HZ) of nearby M dwarfs provide unique opportunities for characterizing their atmospheres and searching for biosignature gases. TRAPPIST-1e, a temperate Earth-sized exoplanet in the HZ of a…
Located at the bottom of the main sequence, ultracool dwarf stars are widespread in the solar neighbourhood. Nevertheless, their extremely low luminosity has left their planetary population largely unexplored, and only one of them,…
The probability that an exoplanet transits its host star is high for planets in close orbits, but drops off rapidly for increasing semimajor axes. This makes transit surveys for planets with large semimajor axes orbiting bright stars…
We present twenty-three transit light curves and seven occultation light curves for the ultra-short period planet WASP-43 b, in addition to eight new measurements of the radial velocity of the star. Thanks to this extensive data set, we…
Several exoplanets have been discovered to date, and the next step is the search for extraterrestrial life. However, it is difficult to estimate the number of life-bearing exoplanets because our only template is based on life on Earth. In…
Interior characterization traditionally relies on individual planetary properties, ignoring correlations between different planets of the same system. For multi-planetary systems, planetary data are generally correlated. This is because,…
TRAPPIST-1 d is generally assumed to be at the boundary between a Venus-like world and an Earth-like world, although recently published works on TRAPPIST-1 b and c raise concerns that TRAPPIST-1 d may be similarly devoid of a substantial…
Whereas the Solar System has Mars and Europa as the best candidates for finding fossil/extant life as we know it - based on complex carbon compounds and liquid water - the 263 (non-pulsar) planetary systems around other stars as known at 15…
A well-known bottleneck for the core-accretion model of giant-planet formation is the loss of the cores into the star by Type-I migration, due to the tidal interactions with the gas disk. It has been shown that a steep surface-density…
Although conjunctions and oppositions frequently occur in planetary systems, eclipse-related phenomena are usually described from an Earth-centric perspective. Space missions to different parts of the Solar system, as well as the mounting…
The James Webb Space Telescope (JWST) has begun to spectrally characterize small exoplanets orbiting M-dwarf stars, but interpretation of these spectra is ambiguous, with stellar, instrumental, or atmospheric origins possible for apparent…
The two known planets in the planetary system of Teegarden's Star are among the most Earth-like exoplanets currently known. Revisiting this nearby planetary system with two planets in the habitable zone aims at a more complete census of…
We study the evolution of protoplanetary discs that would have been precursors of a Trappist-1 like system under the action of accretion and external photoevaporation in different radiation environments. Dust grains swiftly grow above the…
A key feature of the Trappist-1 system is its monotonic decrease in bulk density with growing distance from the central star, which indicates an ice mass fraction that is zero in the innermost planets, b and c, and about 10\% in planets d…
A critically important process affecting the climate evolution and potential habitability of an exoplanet is atmospheric escape, in which high-energy radiation from a star drives the escape of hydrogen atoms and other light elements from a…
Recent observations of the potentially habitable planets TRAPPIST-1 e, f, and g suggest that they possess large water mass fractions of possibly several tens of wt% of water, even though the host star's activity should drive rapid…