Ultrafaint dwarf galaxies (UFDs) are ideal for studying dark matter (DM) due to minimal baryonic effects. UFD observations suggest cored DM profiles. We find that the core radius–stellar mass scaling predicted by fuzzy dark matter (FDM) is at 6 . 1 σ tension with UFD observations. Combining observations from 27 UFDs, the required FDM mass m a = 3

The nature of the minute-to-hour-long fast X-ray transients localized by telescopes such as Chandra, Swift and XMM-Newton remains mysterious, with numerous models suggested for the events. Here we report multi-wavelength observations of EP240315a, a 1,600-s-long transient detected by the Einstein Probe, showing it to have a redshift of z = 4.859

Context. The mechanism behind the heating of the solar chromosphere remains unclear. Friction between neutrals and charges is expected to contribute to plasma heating in a partially ionised plasma (PIP). Aims. We aim to study the efficiency of the frictional heating mechanism in partially ionised plasmas by comparing a single-fluid model (1F) using

The Large Magellanic Cloud (LMC) is a Milky Way (MW) satellite that is massive enough to gravitationally attract the MW disc and inner halo, causing significant motion of the inner MW with respect to the outer halo. In this work, we probe this interaction by constructing a sample of 9866 blue horizontal branch (BHB) stars with radial velocities

We demonstrate the potential of Euclid 's slitless spectroscopy to discover high-redshift ( $z>5$) quasars and their main photometric contaminant, ultracool dwarfs. Sensitive infrared spectroscopy from space is able to efficiently identify both populations, as demonstrated by Euclid Near-Infrared Spectrometer and Photometer Red Grism (NISP ${\rm RG

Euclid is delivering optical and near-infrared imaging data over 14 000 deg 2 on the sky at spatial resolution and surface brightness levels that can be used to understand the morphological transformation of galaxies within groups and clusters. Using the Early Release Observations (ERO) of the Perseus cluster, we demonstrate the capability offered