The Universe is big, in case you weren’t aware. It’s the biggest thing we know of, containing at least 100 Billion Galaxies, each with up to 1 Trillion of their own stars. It’s ludicrously large.
How do we know its so big? A major project completed in 2001 surveyed the Galaxies of the local Universe, and what was found can be summed up in the video below, from Reddit.
The data is from the 2 Micron All Sky Survey (2MASS), whose goal was to map all the galaxies in the known Universe in Infrared. The colours in the above map show Galaxy clusters bound by gravity, and the edges represent a maximum apparent magnitude of 14 as viewed from Earth.