Why has our estimate of the size of the universe changed in the past few centuries?
The estimate of rate of radial expansion is about 1 light year (ly)/year, So, 1 century ago, the radius from BB center of
The radial expansion since BB event 13.77 billion years ago has now
reached 13.77 billion ly. The rate is nearly 1 ly / year.
So, over a century, the radius increases by 100 ly, nearly.