How do you solve for Hubble's constant?

Question

Ariana Acosta · Accepted Answer

If a galaxy is at a distance of P parsec, the angular spacing of its span will be P''. Observe the same galaxy 1 year later, for the angular span Q''. Now, see the explanation..

Observe the same galaxy one year later for the angular span Q''. Q is just very little over P. If a galaxy is at a distance of P parsec, then the angular spacing of its span will be P''. Now, the relative measure #H_0=(Q-P)/P# parsec/year/parsec. It is easy to see that the dimension of #H_0# is #T^(-1)#. This is estimated to be 68, 70, 71, or 72 in standardized units km/s/mega parsec based on data from various sources. I have found reciprocals #{1/H_0}# of dimension T, in befitting units for parity. for age of our universe as 14.4 billion years (by), 14.0 by, 13.8 by and 13.6 by, respectively. #H_0# is a measure for radial expansion, The lateral (span) expansion of galaxy/cluster observed is #(Q-P)# AU/ year = (Q-P)/P AU/year/AU.. This follows from the definition of parsec. Note that #(Q-P)/P# is dimensionless., The purpose of making this note here is to convey what I have understood about #H_0# and related natters.. . . .

Levi Acosta · Answer

undefined The formula to find Hubble's constant is H = v / d, where v is the galaxies' recession velocity and d is the distance to them. The recession velocity can be measured using the Doppler shift of light from far-off galaxies, and the distance can be found using a variety of techniques like standard candles or redshift-distance relations. Once you have the velocity and distance, you can plug them into the formula to find Hubble's constant.