Context. WASP-69 b and KELT-11 b are two low-density hot Jupiters, which are expected to show strong atmospheric features in their transmission spectra. Such features offer valuable insights into the chemical composition, thermal structure, and cloud properties of exoplanet atmospheres. High-resolution spectroscopic observations can be used to

Context. The vast majority of the most iron-poor stars in the Galaxy exhibit strong carbon enhancement, with C/H ratios about two orders of magnitude below solar. This unusual chemical composition likely reflects the properties of the gas cloud from which these stars formed, having been enriched by one, or at most a few, supernovae. A remarkable

The Ultraviolet Near-Infrared Optical Northern Survey (UNIONS) is a "collaboration of collaborations" that is using the Canada─France─Hawai'i Telescope, the Pan-STARRS telescopes, and the Subaru Observatory to obtain ugriz images of a core survey region of 6250 deg 2 of the northern sky. The 10σ point source depth of the data, as measured within a

In this work, we compare galaxies from the NIHAO and HESTIA simulation suites to ultra-diffuse galaxies (UDGs) with spectroscopically measured dynamical masses. For each observed UDG, we identify the simulated dark matter halo that best matches its dynamical mass. In general, observed UDGs are matched to simulated galaxies with lower stellar masses

We present a study of the evolution of the minute-timescale optical variability and of the optical spectroscopic signatures of outflows in the black hole X-ray binary MAXI J1820+070 during its main 2018 outburst and subsequent re-brightenings. Multi-filter, minute-cadence optical light curves were obtained with the Las Cumbres Observatory network