Using the following graph, how would you determine approximately how fast a galaxy would be moving and if it is moving towards us or away from us in km/s if it were 1,000 Mpc from the Milky Way?

Question

John Alexander · Accepted Answer

From the graph, I approximate Hubble constant as 31500/500 = 63 km/s/Mpc, nearly.. Answer: 63000 km/s.

Using the Hubble rate expressed in km/s/Mpc, I was able to approximate the slope of the correlation line as (opposite side ) / (base ) = 31500/500 = 63. This means that, at a distance of 1000 Mpc, the velocity is approximately 63000 km/s.

Hazel Asher · Answer

undefined A galaxy's velocity and direction of motion can be ascertained by following these steps: 1. Locate the galaxy's redshift on the graph; 2. Use the redshift to calculate the velocity using the Hubble's Law equation: v = H0 × d, where d is the distance to the galaxy; 3. Plug the distance of 1,000 Mpc and the value of the Hubble constant into the equation to find the velocity; 4. If the velocity is positive, the galaxy is moving away from us; if the velocity is negative, it is moving towards us.