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[Renton]

Was watching this video and I was wondering why the simplest solution for artificial gravity shouldn't be just having the spaceship's floor perpendicular to the direction of travel and accelerate at a constant rate of 1g for the first half of the journey, then orient the ship 180 degrees and decelerate at the same constant rate for the last half?

[MadMojoMonkey]

Was watching this video and I was wondering why the simplest solution for artificial gravity shouldn't be just having the spaceship's floor perpendicular to the direction of travel and accelerate at a constant rate of 1g for the first half of the journey, then orient the ship 180 degrees and decelerate at the same constant rate for the last half?

In short, acceleration is expensive. Coasting is free. Especially so when the friction is realistically negligible, as in an interplanetary mission.

Mostly it comes down to fuel costs. As in, the cost in added mass of fuel means you need a bigger engine to create the same acceleration.

F = ma -> a = F/m

Force is mass times acceleration - or - acceleration is force divided by mass.

That means the more mass you're moving with the same engine's force reduces the acceleration.

Take into account that the mass of the craft you're accelerating is decreasing over time and you need a bit more robust mathematics, but the result is the same. Acceleration costs mass in the form of fuel. Carrying that fuel around costs still more mass.


There are questions as to whether the long term detriment to human physiology in microgravity is worth the expense of a craft which does what you suggest. Only, it would do so periodically. Long periods of weightlessness, interspersed with relatively short periods of "artificial gravity."