- #1
aurora7790
From deep galaxy counts, it is estimated that there are about 40 billion galaxies in the observable universe (not including probable multitudes of dwarf galaxies too faint to observe). Assuming that the mean age of these galaxies is 10 Gyr, and that each one goes through an AGN episode once, with a mean duration of 108 yr, estimate the total number of quasars that we can see at anyone time.
This was an interesting question that my astronomy professor asked our class the other day, just wanted to see what others came up with!
This was an interesting question that my astronomy professor asked our class the other day, just wanted to see what others came up with!