Question

What is the general relationship between a galaxy's distance from earth and its speed?

Answer 1

Hubble's law is the observation in the physical cosmology that states that the galaxies are moving away from the Earth at a speed proportional to the distance.

The general relation is given as,

$v=H_0D$

Here,

• v is the speed, typically expressed in km/s.

,

• H_0 is the Hubble's constant.

,

• D is the distance from the galaxy to the observer, which changes over time.