A galaxy has a recession velocity of 10,000 km/sec. If the Hubble constant is 65 km/sec. per megaparsec, roughly how far away is the galaxy?
A) 10 megaparsecs
B) 25 megaparsecs
C) 60 megaparsecs
D) 130 megaparsecs

Question

Quizplus · Accepted Answer

The distance to the galaxy can be calculated using Hubble's Law: velocity = Hubble constant × distance. Rearranging gives distance = velocity / Hubble constant = 10,000 km/sec / 65 km/sec per megaparsec ≈ 153.85 megaparsecs. The closest option is 130 megaparsecs.

A Galaxy Has a Recession Velocity of 10,000 Km/sec