The longest continuous spaceflight in history — 437 days aboard the Russian Mir space station, completed by cosmonaut Valeri Polyakov in 1995 — was specifically conducted to prove that a human being could survive a round-trip mission to Mars, in a piece of human endurance that has been waiting unused on a shelf for three decades
The record sits at the top of every list of human spaceflight endurance achievements, has been there since…
