The Milky Way's dwarf galaxies are ideal self-contained systems for us to study early chemical evolution, test theories of galaxy formation on small scales, and understand the assembly history of the Milky Way.
There is currently a tension between various measurements of the expansion rate of the universe. I will give a recap of this issue, and talk about how we use the Cosmic Microwave Background, our most distant observation, to infer the local expansion rate of space.
Measuring weak gravitational lensing (WL), a powerful probe of the distribution of large scale structure, is one of the primary science goals of Euclid and other future large extragalactic surveys with LSST and WFIRST.
In the past few years, a tension has emerged between the current expansion rate of the universe (H0) and the value predicted by early universe probes under the assumption of a standard LCDM cosmology.
