Did Scientists Discover Alien Mega-Structures?

Did scientists find Dyson spheres around stars? Neil deGrasse Tyson explores what an alien civilization might look like to us, the Kardashev Scale, and Dyson Spheres.

Learn what researchers found around previously discovered stars. We break down the Kardashev Scale and what to look for when detecting alien civilizations. Plus, learn about Freeman Dyson and how he thought a Type II Civilization might work.