Latest astronomy nouvelles

Advanced statistical methods help clarify planetary signals hidden within precise radial velocity data. By systematically testing how individual measurements influence a model, researchers have refined the mass estimate of HD 119130 b, clarified the orbital architecture of the Gliese 4276 system, and confirmed the three-planet structure orbiting Gliese 357 by testing for predictive consistency....

Observations of the disintegrating rocky planet BD+05 4868 b reveal potential signatures of oxygen escaping from its surface. By analyzing the planet during transit, the recorded data suggest the presence of a mineral-vapor outflow. This finding provides insights into how intensely irradiated rocky worlds lose their material through evaporation processes....

Researchers have analyzed the atmospheres of eight sub-Neptune planets orbiting Red dwarf stars using the James Webb Space Telescope. By studying the mean molecular weight of their gaseous envelopes, the team identified a new category of intermediate planets, dubbed hybrid worlds, which do not fit the traditional definitions of simple gas-enveloped rocks or water-rich worlds formed in the outer solar system....

Observations of the protoplanetary disc surrounding the star HD 139614 reveal complex light patterns caused by an inclined planet. By analyzing scattered-light images, researchers identified shifting brightness in the inner ring and a distinct spiral structure. A physical model suggests that a tilted planet forces inner parts of the disc to warp and precess, casting long-lasting shadows across the outer regions....

Magnetic fields play a vital role in shaping the atmospheres of planets, yet measuring them around close-in worlds remains difficult. A recent analysis of the ultra-hot Jupiter KELT-9 b sought to detect a magnetic field using the Zeeman effect in atomic lines. While a marginal signal was observed in 2025, subsequent observations failed to replicate the result, leaving the presence of the field unconfirmed....

A large-scale analysis of TESS mission data has confirmed 29 new hot and warm Jupiter-sized planets orbiting bright stars. By using space-based transits and ground-based observations, the study provides a consistent dataset of these massive worlds, revealing new details about their orbits, masses, and stellar environments, including the identification of three new bound stellar companions in these systems....

Researchers have identified 29 potential outer giant planets orbiting within existing exoplanetary systems by analyzing stellar motion data. By utilizing measurements from the Hipparcos and Gaia space missions, the team detected the subtle gravitational tugs these distant companions exert on their host stars, providing new targets for future observations to understand how these planets shape their systems....

Modern planetary science relies heavily on advanced simulations to interpret the light signatures collected by observatories like the James Webb Space Telescope. These simulations often use a method called amortized simulation-based inference, which is designed to identify the atmospheric conditions of distant worlds. However, this process has faced significant challenges when applied to real data, often producing results that do not align with p...

The planetary system orbiting the star HD 65216 contains at least two giant planets moving on elongated, eccentric orbits. By combining radial velocity data, which measures the subtle wobbling motion of a star caused by the gravitational tug of orbiting planets, with astrometric measurements, which track the star's precise movement across the sky, researchers have updated the physical characteristics and orbital paths of these massive worlds....