One of the big problems surrounding a proposed manned mission to Mars is the massive amount of fuel required for the journey — but scientists might’ve just figured out a way to cut that down. A lot.
Up to this point, NASA has used something called the Hohmann transfer approach to send satellites and rovers to Mars, which requires a whole lot of planning and timing to ensure the craft and Mars are on the same trajectory to be as close as possible when it gets there. That’s important, because the distance between Earth and Mars changes drastically depending on the orbit, and we only have a launch window of once every 26 months to get it right.
Well, that could be changing if mathematicians Francesco Topputo and Edward Belbruno are right about using a strategy called ballistic capture to get a ship to Mars. Instead of having to hit the “bullseye” and blow a ton of fuel to slow down once the craft reaches the Red Planet, this strategy uses Mars’ motion as an asset to have a future craft basically just cruise a bit slower than the planet while allowing Mars's own gravity to rope it into a stable orbit.
Why’s it matter? A proposed manned mission would use approximately 25 percent of its fuel to slow down once it reached the planet, but this strategy would let gravity do most of that work, meaning lower fuel needs overall — so we could use a smaller rocket, or have more room for additional people and stuff. When you’re traveling 140+ million miles, that extra leg room can make a lot of difference.