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Hubble's Law help!

Hubble's Law states that the apparent receding velocity of body in space is proportional to the distance from Earth. So if we take Hubble's constant to be 70km per second per Mpc, that means that a body that's 1Mpc away from us appears to be receding at a velocity of 70km per second. When it has moved another parsec say, will its velocity of recession appear to have increased as its distance from Earth has increased OR will the velocity remain the same and Hubble's constant have changed (hence why it's reciprocal is approximately the time since the Big Bang)?

Reply 1

Joinedup

Original post by hhattiecc

The law is a description of what we see in the current era... if/how h₀ is changing is an open question in cosmology. at the moment observations of CMB and BAO (and possibly soon weak lensing) are putting tighter constraints on the cosmological models every few years.
it's an exciting time.