Spoiler alert – in the future there never will be artificial gravity – astronauts won’t be able to walk around in spaceships.
In the movies most spaceships like the Starship Enterprise employ a convenient technology they call “artificial gravity” to overcome this weightlessness problem. In a few movies they even rotate parts of the ship, though the part of the ship that rotates often has no relevance to the part of the space ship people are walking around in.
No matter. Walking around is a convenient way to avoid a big budget.
Weightlessness is a pesky little problem and we’ve become comfortable accepting that on spaceships of the future you’ll be solidly on the floor. Venture outside to fix anything and you’ll be weightless maybe (unless you use something they call “gravity boots”) but inside, put something on a table and it stays on the table. People won’t be weightless in spaceships in the future.
That’s why they call this stuff science fiction. There won’t be any artificial gravity and to the dismay of Kirk and Spock a spaceship that looks like their’s will have weightless people inside.
Another design, a real design, for a spaceship that would actually have “artificial gravity” is called the Von Braun spacewheel, and envisioned in movies wanting more realism. The Von Braun spacewheel looks like this contraption. Of course, it spins and as it does the occupants inside experience centripetal acceleration, also sometimes known as artificial gravity.
So why doesn’t NASA build one of these?
Well, along comes the real world, pushing Hollywood right outta there.
- They don’t have the lifting power to get all the parts up there. It’s doubtful the Falcon-heavy will be utilized for such a project.
- Assembly and then pressuring it inside are formidable obstacles. This is not impossible, but beyond available budgets.
- Zero gravity laboratories, like the present International Space Station have taught us that research in microgravity environments is valuable.
- With exercise, astronauts do just fine, so why bother?
Alas, we may send people to Mars one day, but those poor ol’ chaps will be weightless all the way, and exercise like they do on the ISS.