Question

What is the mass of the universe? How was this determined?

Answer 1

`6*10^51 kg`

Explanation:

A total mass of the visible matter of about `6*10^51 kg`

The mass density of visible matter (i.e., galaxies) in the Universe is estimated at `3*10^-28 (kg)/m^3^`. The radius of the visible Universe is estimated at `1.7*10^26 m`. Plus or minus 20 percent. Therefore, you can compute the mass of the universe.

Reference: https://people.cs.umass.edu/~immerman/stanford/universe.html