In the 1920s this American astronomer provided the earliest evidence that the universe was expanding
In the early 1920s, American astronomer Edwin P. Hubble was 
able to ... Hubble realized that if he could measure the universe's speed of 
expansion,... [DOC] [TLE] big-bang theory facts, information, pictures | Encyclopedia.com ... [PAR] Evidence that the universe was evolving did not begin to accumulate until the 
1920s.