Question

If a life form on a planet in a distant galaxy measured the Hubble constant from its location, how would it compare to the value measured from Earth? (Assume the same unit of measuremeant is used.)

1. same

2. lower

3. higher

Answer 1

Using the ideal hubble law

Any two points which are moving away from the origin, each along straight lines and with speed proportional to distance from the origin, will be moving away from each other with a speed proportional to their distance apart.

An observation stemming from this theorem is that seeing objects recede from us on Earth is not an indication that Earth is near to a center from which the expansion is occurring, but rather that every observer in an expanding universe will see objects receding from them.

The law is often expressed by the equation v = H₀D, with H₀ the constant of proportionality (Hubble constant). This means the far galaxy would measure the same constant (uncertainty could make this value a little different, the current hubble constant on earth has 15% of uncertainty)