What is Hubble's law?
A)The luminosity of the Cepheid variable star is directly proportional to its pulsation period.
B)The recession velocity of a galaxy is inversely proportional to its distance.
C)The faster a spiral galaxy's rotation speed, the less luminous it is.
D)The recession velocity of a galaxy is directly proportional to its distance.
E)The faster a spiral galaxy's rotation speed, the more luminous it is.

Question

Quizplus · Accepted Answer

Hubble's law states that the recession velocity of a galaxy is directly proportional to its distance. This means that the further away a galaxy is from us, the faster it appears to be moving away from us. This law is consistent with the idea that the universe is expanding.

What Is Hubble's Law