A theory as to why we haven't heard from aliens which renowned theoretical physicist and cosmologist Stephen Hawking agreed with has resurfaced online. Planet Earth is about the size of a speck of ...

Debunking alien claims matters, but so does telling richer, more compelling stories about how humans shaped their own past.

Add Yahoo as a preferred source to see more of our stories on Google. Photo Credit: Kyle Mazza/Anadolu via Getty Images Barack Obama is clarifying what appeared to be his confirmation that aliens did ...