Astronomers have figured out, among other things, how big the Universe is. Most people have no idea how they figured it out.

This video by the Royal Observatory Greenwich does a fantastical job of explaining it to mere mortals using no math but outstanding visualization. It’s so well made… you gotta watch it if you haven’t yet. Yes, even if you are one of my dear astronomer readers:

Measuring the Universe from Royal Observatory Greenwich on Vimeo.