Question

From their redshifts, calculate the speed at which each of the galaxies is moving away from us. give your answers in km/s.

Answer 1

The math suggests that for every parsec the rate of moving away is 71 km/s, so when two galaxies are separated by two parsecs we come to 142 km/s speed of moving away from each other. If we take the first light ever (from what is known so far) the cosmic microwave radiation, is 46 billion light-years away from us at all directions, which comes at 4,200 megaparsecs, which comes at 13.7 billion light-years, so it will come to 29,820,000 km/s. It all depends from the distance between the galaxies which is calculated by their type of colour and movement in comparison to other galaxies.