Explores the expansion and Hubble law in astrophysics, covering the Hubble constant, cosmological redshift, critical density, and cosmic background radiation.
Explores the classification and statistics of AGN, black holes, unified AGN model, variability, megamasers, orbital motion measurement, and time-delay cosmography.
Explores the fundamental problem of distance in astronomy and discusses various methods for distance measurement, including wide-angle astrometry and detached eclipsing binary distances.
