Specifically traces the impact of Einstein's ideas on astronomy, including the way we interpret observations of stars and galaxies.

Includes comments from principals in important discoveries, illuminating the processes behind these results.

Presents many applications of relativity that have not been shown in earlier popular-level books and illustrates how deeply physics permeates the way we interpret many astronomical phenomena.

Highlights light-travel delays in cosmic jets, using gravitational lensing to trace cosmic mass distribution.

Illustrations employ new and archival data from ground- and space-based observatories.