Astronomers calculated this velocity in 2009–2013, and found that it was around 46,200 mph per million light years, or 67 km/s/sMpc.
Using Cepheid variables, or pulsing stars, is the second method. The outer layers of dying stars, which flash like broken city lights in the distance, are used by astronomers.
These Cepheid stars may be linked together to form a “cosmic distance ladder” by measuring their brightness,
Which enables us to delve farther into the history of the universe. This allows one to get an accurate figure that indicates the rate at which the universe is expanding.
Adam Riess, a physics and astronomy professor at Johns Hopkins University, and his colleagues calculated the expansion rate of the universe using the second technique,
