“There are about one hundred billion galaxies within this visible universe and the average density of material within a galaxy is about… — John D. Barrow Copy Share Image
“Distant galaxies now visible in the night sky will ultimately disappear beyond an unreachable horizon, receding from us faster than the speed… — Neil deGrasse Tyson Copy Share Image
It bears mentioning that the Milky Way is only one of 150 billion galaxies visible to our telescopes - and each of… — Seth Shostak Copy Share Image
