Apr 20, 2015. Astronomers have discovered what they say is the largest known structure in the universe: an incredibly big hole. The “supervoid”, as it is. In 1933, Fritz Zwicky—a Swiss astronomer working at CalTech—had an amazing revelation. He realized that the amount of matter that we can see through our telescopes doesn’t match the behavior of the Universe. There had to be something. Apr 15, 1985. We obtain a…