Related papers: Time-variable electromagnetic star-planet interact…
Magnetic fields of exoplanets are important in shielding the planets from cosmic rays and interplanetary plasma. Due to the interaction with the electrons from their host stars, the exoplanetary magnetospheres are predicted to have both…
We study the spin evolution of close-in planets in compact multi-planetary systems. The rotation period of these planets is often assumed to be synchronous with the orbital period due to tidal dissipation. Here we show that planet-planet…
(Abridged) We search for evidence of star-planet magnetic interactions in the nearby Proxima Centauri planetary system using high-quality, high-spectral-resolution optical observations. We measure a photospheric stellar rotation period of…
The majority of potentially habitable exoplanets detected orbit stars cooler than the Sun, and therefore are irradiated by a stellar spectrum peaking at longer wavelengths than that incident on Earth. Here, we present results from a set of…
The obliquities of planet-hosting stars are clues about the formation of planetary systems. Previous observations led to the hypothesis that for close-in giant planets, spin-orbit alignment is enforced by tidal interactions. Here, we…
Photometric follow-ups of transiting exoplanets may lead to discoveries of additional, less massive bodies in extrasolar systems. This is possible by detecting and then analysing variations in transit timing of transiting exoplanets. We…
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 terrestrial planets that formed in the same…
The surface rotations of some red giants are so fast that they must have been spun up by tidal interaction with a close companion, either another star, a brown dwarf, or a planet. We focus here on the case of red giants that are spun up by…
We perform numerical simulations of the TRAPPIST-1 system of seven exoplanets orbiting a nearby M dwarf, starting with a previously suggested stable configuration. The long-term stability of this configuration is confirmed, but the motion…
Stratosphere circulation is important to interpret abundances of photo-chemically produced compounds like ozone that we aim to observe to assess habitability of exoplanets. We thus investigate a tidally locked ExoEarth scenario for…
The TRAPPIST-1 system provides an exquisite laboratory for advancing our understanding exoplanetary atmospheres, compositions, dynamics and architectures. A remarkable aspect of TRAPPIST-1 is that it represents the longest known resonance…
Star-planet magnetic interactions (SPMI) occurring in the sub-Alfvenic regime can, in principle, induce stellar chromospheric hotspots. Currently, estimates of the power generated by SPMI primarily rely on analytical scaling laws that…
The high energy radiation environment around M dwarf stars strongly impacts the characteristics of close-in exoplanet atmospheres, but these wavelengths are difficult to observe due to geocoronal and interstellar contamination. On account…
Transit timing analysis may be an effective method of discovering additional bodies in extrasolar systems which harbour transiting exoplanets. The deviations from the Keplerian motion, caused by mutual gravitational interactions between…
We investigate the formation of bow shocks around exoplanets as a result of the interaction of the planet with the coronal material of the host star, focusing on physical causes that can lead to temporal variations in the shock…
Recently, four additional Earth-mass planets were discovered orbiting the nearby ultracool M8 dwarf TRAPPIST-1, making a remarkable total of seven planets with equilibrium temperatures compatible with the presence of liquid water on their…
Planetary systems with close-in giant planets can experience magnetic star-planet interactions that modify the activity levels of their host stars. The induced activity is known to strongly depend on the magnetic moment of the interacting…
About a dozen exoplanetary systems have been discovered with three or more planets participating in a sequence of mean-motion resonances. The unique and complex architectures of these so-called "resonant chains" motivate efforts to…
The method of gyrochronology relates the age of its star to its rotation period. However, recent evidence of deviations from gyrochronology relations was reported in the literature. Here, we study the influence of tidal interaction between…
Most (~82%) of the over 4000 confirmed exoplanets known today orbit very close to their host stars, within 0.5 au. Planets at such small orbital distances can result in significant interactions with their host stars, which can induce…