The Microlensing Observations in Astrophysics (MOA) collaboration is an international research project that uses gravitational microlensing for the discovery of exoplanets. MOA was initiated in the late 1990s and primarily involves institutions from Japan and New Zealand. The collaboration's observation site is the Mount John Observatory in New

Context. Massive contact binaries (CBs) are crucial objects for understanding close binary evolution and stellar mergers. Study of these objects has been hampered by a scarcity of observed systems, particularly of B-type systems which are expected to dominate this class. Aims. We bridge this observational gap by mining a large sample of massive CB

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