Firing a gun inside a fragile spacecraft filled with oxygen could be disastrous - so the world has been stunned at the revelation that Soviet cosmonauts used to pack shotguns.
Writer James Simpson recently confirmed that the 'myth' about Soviet spacemen being armed with shotguns was, in fact, true.
Not only that, but Russian space explorers were carrying weapons until very recently - until 2007, in fact.
Cosmonauts weren't tooling up for a fight with NASA astronauts, though.
The weapons were part of a 'survival kit' which was designed to help if the crew's craft veered off course during landing or take-off.
The shotgun was there to kill bears in case the crew landed in a remote area, Simpson revealed.
It had three barrels, and the weapon also had a sharp blade which could be used as a machete in jungle areas, or as an axe to chop wood.
'Having a gun inside a thin-walled spacecraft filled with oxygen sounds crazy but the Soviets had their reasons.
'Much of Russia is desolate wilderness. A single mishap during descent could strand cosmonauts in the middle of nowhere.'
Russian cosmonauts were armed with the TP-82 shotgun until 2007 - and they still carry a gunless version of the same survival kit.