If we went back in time 10 billion years,how would we expect a plot of galaxy luminosities against colors to change?
A)The red cloud would be much more sparse.
B)The blue cloud would be much more heavily populated.
C)The blue cloud would be much less populated.
D)Both A and B

Question

Quizplus · Accepted Answer

10 billion years ago, the universe was much younger, and galaxies were in earlier stages of their evolution. This means there would be more young, hot, and therefore blue stars, making the blue cloud more heavily populated. At the same time, there would be fewer older, cooler, and therefore red stars, making the red cloud more sparse.

If We Went Back in Time 10 Billion Years,how Would