What did Edwin Hubble study in the Andromeda Galaxy that proved it was an individual galaxy and not part of our own Milky Way?
A) Cepheid stars
B) Type Ia supernovae
C) globular clusters
D) red giant stars
E) RR Lyrae variables

Question

Quizplus · Accepted Answer

Edwin Hubble studied Cepheid stars in the Andromeda Galaxy, which allowed him to determine their distance from Earth. This distance was much greater than the size of the Milky Way, proving that Andromeda was a separate galaxy.

What Did Edwin Hubble Study in the Andromeda Galaxy That