New videos DAILY: https://bigth.ink/youtube Join Big Think Edge for exclusive videos: https://bigth.ink/Edge Are UFOs actually alien spacecraft visiting Earth? They might be, says Neil deGrasse Tyson, but if you want to make that claim you better bring the evidence to support it. Eyewitness testimony is the lowest form of evidence. To measure what is true or not true in the world, we require data — … Continue reading Neil deGrasse Tyson: Want to prove aliens exist? Do this