Few scientific terms express a sense of sheer enormity more than the word "galaxy." Galaxies are massively massive. They're filled with more stars than any single person could count. They're billions of times brighter than our own Sun! Galaxies are huge! Except for Segue 2.
The total number of stars in the Universe "is likely three times bigger than realized." Yale University astronomer Pieter van Dokkum says there are "possibly trillions of Earths orbiting these stars," dramatically increasing the possibility of finding alien civilizations.