Artificial Gravity in Space

By: Davan Mulligan

Artificial gravity may be the key to long-term space travel. A number of health issues arise while in zero-gravity environments, like loss of muscle mass, bone density, space blindness, and more. Artificial gravity seems like a solution that solves all of these problems at once. So, how can we achieve it?

A Rotating Spaceship

Think of a spinning carnival ride. Centrifugal force is the force that you feel as you’re pulled to the outer walls of the ride. Centripetal force is the force that is making the ride spin. Using centripetal force, we can create a sort of ‘spin gravity.’ This would essentially be a rotating spacecraft that results in a “pseudo gravitational effect.” Using centripetal force to create artificial gravity in space works theoretically, but the mechanics behind realistically using it poses some problems. 

First and foremost, “cross-coupled illusion” is an issue with this type of artificial gravity. This occurs when a person affected by centrifugal force turns their head. The inner ear is disrupted, and the person experiences an unpleasant falling sensation. 

Another issue comes with the size of the craft. If it is not large enough, the force felt by one’s head versus one’s feet is considerably different, causing motion sickness. Creating a spacecraft with a big enough radius is costly. One of the leading reasons preventing us from making a centripetal spacecraft is the high-cost. The manufacturing challenges posed by such a large spacecraft are also a roadblock.

In 2002, NASA found that to achieve 1g of gravity (Earth’s gravity) using centripetal force, a spacecraft must have a rotational speed of 4 RPM with a radius of 56m. Accelerating a ship to this speed, and decelerating it once it reaches its destination, could be a problem.

The Coriolis Effect

Coriolis force is an inertial force that makes an object in a centrifuge go left or right. For example, if a spacecraft was rotating clockwise, and an astronaut jumped, they would land slightly to the left of where they initially jumped from. In the same scenario, if an astronaut was climbing a ladder towards the centre of the spacecraft, they would feel a slight tug to the left. When descending from the ladder, they would feel a tug to their right.

Overall, it seems like there is a ways to go before we can achieve artificial gravity. With that said, it is not impossible and just needs further research and time. Hopefully, one day soon we can achieve artificial gravity in space.