Gravitational waves have been used to measure the Hubble constant before, but the uncertainties were too large to provide competitive constraints. However, using lensed gravitational wave events could be a game-changer.
A reanalysis of the cosmic microwave background data suggests a slightly more curved Universe than previously measured.
New observations of pulsing variable stars weigh in on the Hubble tension. Find out how in this Astrobite!
The discovery of medium-sized black holes allow us to trace the history of the giant black holes in the center of galaxies.
Four new Milky Way dwarf satellite candidates were discovered in 2015 using the Dark Energy Survey. Fainter imaging data are used to further investigate their exact nature.
Observations of dim galaxies lensed by foreground clusters provides a way of measuring the progression of reionization.