The mysteries surrounding the death of Yuri Gagarin — the first human to ever travel into outer space — may finally have been solved thanks to fellow Russian cosmonaut Alexey Leonov. Gagarin's death in 1968 was the result of a plane crash, but just how he came to crash has been subject to conspiracies and speculation for decades. Previous theories have suggested that while piloting a test flight Gagarin made a poor maneuver or blacked out. But according to Russia Today, Leonov was there that day, and he's finally spoken out to say that he believes a supersonic jet knocked Gagarin's plane into a tailspin that he couldn't recover from.

Why Leonov didn't speak until now underscores why the cause of Gagarin's crash was covered up. According to RT, the military jet was supposed to be flying quite high in the air — over six miles up — but it was instead incredibly close to land, only about one-third of a mile high. The slip up may have been an embarrassment that the government didn't want publicized, especially following the death of an important national figure. Leonov was only recently given clearance to see the original incident reports, finally allowing him to put together what actually happened. RT reports that between Leonov's memories, some computer simulations, and peer review, this account could be the final word on Gagarin's death.