Getting to Mars is never going to be cheap. But a couple of mathematicians have figured out how to shave some significant bucks off the price tag. Rather than fly to the red planet when it’s orbit brings it closest, the craft will “meet” it on the way. The strategy is called ballistic capture and involves launching the ship into a Mars-like orbit, but moving slower than than the planet itself.
There are myriad reasons why getting from Earth to Mars is hard, but chief among them are two 1) the massive amount of fuel needed and 2) a launch window that is limited to every 26 months, when the two planets are in optimal alignment. A couple of mathematicians have calculated a new path to Mars that solves both — and it’s far from a straight line. Mapping a route to Mars, of course, is more complicated than mapping any Earth-bound route. The distance between the two planets is constantly growing or shrinking, depending on their orbits around the sun. (That’s why the optimal launch window only opens every 26 months.) And you have to take into account how gravity from the Earth, Mars, and the sun will pull a spacecraft off its course.