Humanity, life on Earth, our planet itself—how did everything in the universe come into being? Well, as far as we know, it all started with the Big Bang. But while the Big Bang theory has certainly been in place for a while, we didn’t always have proof that it occurred. But it started with a hypothesis: if the Big Bang really happened, we should still be able to hear the ripples it created. See the full episode and learn more about how Penzias and Wilson changed cosmology forever in the video above.