There have been some memorable fight scenes in space science fiction over the years, but how many of them are an accurate representation of how the struggle would play out in microgravity?
Let’s look first at one-on-one combat.
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We don’t see many fights between individuals wearing bulky spacesuits, which makes sense, given they would hinder movement.
It probably wouldn’t make for a very engaging action scene.
So we’ll assume we’re talking about a fight inside, where the air is oxygenated.
Momentum would be the third opponent in any fist fight. Newton’s laws dictate that for every action there is an equal and opposite reaction.
Down on Earth, punching someone would exert a force on them but also on you, though we can brace ourselves against the ground.
In microgravity, however, the punch would send us backwards.
We could use this to our advantage: pushing against a wall to give our attack even greater force.
If you’re bringing guns into this space fight, you’ll get the same problem.
The recoil would start you moving in the opposite direction at the speed of a few centimetres per second (though not enough to make Colin Farrell’s escape in the 2012 version of Total Recall realistic).
What about fights between spaceships? Guns and lasers would both work, though they too would exert an equal and opposite force on your own ship.
To remain stationary, you’d need to put some thrusters on.
Disappointingly, there would be no ‘pew! pew!’ sound because, of course, there’s no sound in space.
This article appeared in the February 2025 issue of BBC Sky at Night Magazine.
