Scientists decided to point the Hubble Telescope towards what appeared to be a cold, dead spot in space and then take multiple exposures over a few months time (a total of about 11 days exposure time). It would be about like you looking through a little straw at one point in the sky. The result is the image below, called the
Hubble Ultra Deep Field image. They estimate that there are about 10,000 galaxies in the image. Each galaxy would probably contain an average of 100,000,000 stars.