We investigate a new class of habitable planets composed of water-rich interiors with
massive oceans underlying H 2-rich atmospheres, referred to here as Hycean worlds. With …

We report on precise Doppler measurements of L231-32 (TOI-270), a nearby M dwarf (d= 22
pc, M⋆= 0.39 M⊙, R⋆= 0.38 R⊙), which hosts three transiting planets that were recently …

With no analogues in the Solar System, the discovery of thousands of exoplanets with
masses and radii intermediate between Earth and Neptune was one of the big surprises of …

The exoplanet population characterized by relatively short orbital periods (P< 100 d) around
solar-type stars is dominated by super-Earths and sub-Neptunes. However, these planets …

High resolution transit spectroscopy has proven to be a reliable technique for the
characterization of the chemical composition of exoplanet atmospheres. Taking advantage …

The metastable helium triplet in the near-infrared (10 833 Å) is among the most important
probes of exoplanet atmospheres. It can trace their extended outer layers and constrain …

The warm Neptune GJ 3470b transits a nearby (d= 29 pc) bright slowly rotating M1. 5-dwarf
star. Using spectroscopic observations during two transits with the newly commissioned …

Context. Because of its proximity to an active K-type star, the hot Jupiter WASP-80b has
been identified as a possible excellent target for detecting and measuring He I absorption in …

We report the discovery and characterization of two transiting planets around the bright M1 V
star LP 961-53 (TOI-776, J= 8.5 mag, M= 0.54±0.03 M⊙) detected during Sector 10 …

Multiplanet systems orbiting M dwarfs provide valuable tests of theories of small-planet
formation and evolution. K2-3 is an early M dwarf hosting three small exoplanets (1.5–2.0 …