Currently, when NASA plans a trip to Mars the agency waits for Mars to reach its closest point to Earth in its orbit. That window of opportunity comes around every 26 months. When the spacecraft reaches Mars, after 6 months of travel, the “Hohmann transfer” approach is used to put the spacecraft into Mars’ orbit or on the surface.

That approach uses about 25 percent of a ships fuel supply to slow the spacecraft down and put it in the right location. If the calculations are off by even a small amount there is a risk that the spacecraft will miss Mars entirely or crash into its surface. This method also represents a large cost because the fuel is expensive and it currently costs $10 thousand to put a pound of cargo, including fuel, into orbit.

Now two mathematicians, working for the Boeing corporation, have come up with an approach that could revolutionize Mars Travel. The “ballistic capture” method could dramatically reduce the amount of fuel required for a Mars trip, decrease the chance of missing the landing and eliminate the need to wait 26 months for a launch window.

Francesco Topputo and Edward Belbruno published a paper advocating the new approach on ArXiv and have submitted it to the journal Celestial Mechanics and Dynamical Astronomy.

The ballistic capture method involves launching a craft into the path of Mars orbit rather than directly at the planet. The craft then holds its position until Mars comes along in its standard orbit. The planets gravitational field then grabs the craft as it goes by and pulls it into orbit.

Belbruno laid out the method originally while working at NASA’s Jet Propulsion Laboratory as a method for moving probes to the moon. This approach was used by the Japanes “Hiten” mission in 1991 and NASA’s “GRAIL” mission in 2011.

Using the maneuver to reach Mars originally seemed impossible because of the velocity is much higher than the moons. There is also a need to account for the gravity of the Sun and Jupiter when aiming for Mars. However, Topputo and Belbruno felt that they had made progress and Boeing, a major contractor for NASA’s Space Launch System, funded further study of the question.

“It’s an eye-opener, it could be a pretty big step for us and really save us resources and capability, which is always what we’re looking for,” James Green, director of NASA’s Planetary Science Division told Scientific American.

The approach is not without its problems. First of all it would put things in orbit roughly 20,000 miles above the surface of Mars. So some fuel would be required, after the craft was in orbit, to put it closer to the surface or land it.

The bigger problem is the time line. There are already significant concerns about the six months that astronauts would have to spend in space. The psychological impact of that much time in close quarters and the large amounts of solar radiation that they would be exposed to make extending their time in space highly undesirable.

However, for robotic missions and more importantly for re-supply missions the ballistic capture method could achieve considerable savings. Until now potential Mars explorers have been operating under the assumption that resupply missions could only occur every 26 months. Using ballistic capture, resupply missions could happen as often as necessary.

It is still early days for applying ballistic capture to Mars missions and there is still a great deal of work to be done but Belbruno is hopeful. “The route to the moon I found in 1991 was thought to be perhaps the only application of my theory. I am very excited about this Mars result,” he said.