LTT 9779 b is an ultra-hot Neptune (R p ≍ 4.7 R ⊕, M p ≍ 29 M ⊕) orbiting its Sun-like host star in just 19 hr, placing it deep within the "hot-Neptune desert," where Neptunian planets are seldom found. We present new James Webb Space Telescope NIRSpec G395H phase curve observations that probe its atmospheric composition in unprecedented detail. At

The radii of small exoplanets form two populations, super-Earths and sub-Neptunes, separated by a gap known as the radius valley. This feature could be produced by the removal of atmospheres by stellar or internal heating or by the lack of an initial envelope. We used transit photometry and radial velocity measurements to detect and characterize

I present ExoIris, a user-friendly Python package for exoplanet transmission and emission spectroscopy. Unlike existing tools, ExoIris models two-dimensional spectrophotometric transit time series directly and supports the joint analysis of multiple datasets obtained with different instruments and at different epochs, as well as modeling stellar

The tomographic approach to analysing the 3 × 2 pt signal involves dividing the observed galaxy sample into a configuration of redshift bins. We present a simulation-based method to explore the optimum tomographic binning strategy for Euclid, focussing on the expected configuration of its first major data release (DR1). To do so, we 1) simulated a

The Euclid space telescope of the European Space Agency (ESA) is designed to provide sensitive and accurate measurements of weak gravitational lensing distortions over wide areas on the sky. Here, we present a weak gravitational lensing analysis of early Euclid observations obtained for the field around the massive galaxy cluster Abell 2390 as part

Context. The line-of-sight (l.o.s.) velocity dispersion (σ los) of the stellar component of ultra-faint-dwarf galaxies (UFDs) typically ranges from 3 to 6 km s −1. Applying standard mass estimators, this hints at extreme dynamical mass-to-light ratios (M/L) of approximately ∼100─5000 M ⊙/L ⊙ within the half-light radius (r 1/2), making UFDs the