X-ray observations of the optically selected z = 6.025 quasi-stellar object (QSO) CFHQS J164121+375520 (hereafter J1641) revealed that its flux dropped by a factor of ≳7 between 2018, when it was a bright and soft X-ray source, and 2021. Such a strong variability amplitude has not been observed before among z > 6 QSOs, and the underlying physical

The near-Earth asteroid (98943) Torifune, previously designated 2001 CC 21, is the flyby target of the Hayabusa2 extended mission, nicknamed Hayabusa2# (Small Hazardous Asteroid Reconnaissance Probe (SHARP)). The ground-based telescope observations offer a key science input for the mission's scientific investigation. During 2022–2024, this asteroid

We present ∼115 new spectroscopically identified members of the GD-1 tidal stream observed with the 5000-fiber Dark Energy Spectroscopic Instrument (DESI). We confirm the existence of a "cocoon," which is a broad (FWHM ∼ 2 932 ∼ 460 pc) and kinematically hot (velocity dispersion, σ ∼ 5–8 km s ‑1) component that surrounds a narrower (FWHM ∼ 0 353 ∼

Gravitational redshift and Doppler effects give rise to an antisymmetric component of the galaxy correlation function when cross-correlating two galaxy populations or two different tracers. In this paper, we assess the detectability of these effects in the Euclid spectroscopic galaxy survey. We model the impact of gravitational redshift on the

The ESA Euclid mission will survey more than 14 000 deg 2 of the sky in visible and near-infrared wavelengths, mapping the extragalactic sky to constrain our cosmological model of the Universe. Although the survey focusses on regions further than 15° from the ecliptic, it should allow for the detection of more than about 10 5 Solar System objects

We report the discovery of a complete Einstein ring around the elliptical galaxy NGC 6505, at z = 0.042. This is the first strong gravitational lens discovered in Euclid and the first in an NGC object from any survey. The combination of the low redshift of the lens galaxy, the brightness of the source galaxy (I E = 18.1 lensed, I E = 21.3 unlensed)