Using a relatively new and potentially more precise technique for measuring cosmic distances, which employs the average stellar brightness within giant elliptical galaxies as a rung on the distance ladder, astronomers calculate a rate -- 73.3 kilometers per second per megaparsec, give or take 2.5 km/sec/Mpc -- that lies in the middle of three other good estimates, including the gold standard estimate from Type Ia supernovae. This means that for every megaparsec -- 3.3 million light years, or 3 billion trillion kilometers -- from Earth, the universe is expanding an extra 73.3 ±2.5 kilometers per second. The average from the three other techniques is 73.5 ±1.4 km/sec/Mpc.
How fast is the universe expanding? Galaxies provide one answer
https://www.sciencedaily.com/releases/2021/03/210308165239.htm
John P. Blakeslee, Joseph B. Jensen, Chung-Pei Ma, Peter A. Milne, Jenny E. Greene. The Hubble Constant from Infrared Surface Brightness Fluctuation Distances. The Astrophysical Journal, 2021 [abstract]
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