If present during the epoch of reionization, dark stars — hypothetical stars powered by the annihilation of dark matter — could provide an explanation for the observed optical depth of the cosmic microwave background.
A new catalog of 5,598 ultra-diffuse galaxy candidates, 1,079 of which have distance estimates, enables researchers to compare the characteristics of these unusual galaxies to those of typical elliptical galaxies.
New observations reveal that the highly variable winds arising from the accretion disk at the center of the active galaxy NGC 5548 are linked to the large changes in the galaxy’s X-ray flux.
Accretion disks around rogue intermediate-mass black holes are a potential explanation for the double-peaked hydrogen emission lines observed in gas clouds in galaxies in the local universe.
Transit observations can’t say which star in a binary system hosts a transiting exoplanet, but models can help; in one study, 70% of sampled transiting planets orbited the primary star in the system.
Pitted impact deposits within craters are spectrally distinct from those in crater ejecta, potentially due to oxidation processes, meaning that these regions are different in ways apart from space weathering.