Scientist's Accidental Find Could Cut Mars Trip to 5 Months

Mars just got a whole lot closer, thanks to a scientist who wasn't even looking for a shortcut.

Marcelo de Oliveira Souza was studying near-Earth asteroids in 2015 when he noticed something odd about one rock's early trajectory. The path of asteroid 2001 CA21 hinted at a route between Earth and Mars that seemed impossibly fast.

"I was not looking for this," Souza told Live Science. But what he found could transform how we reach the Red Planet.

Current Mars missions take seven to 10 months just to get there. Because Earth and Mars only align for fuel-efficient trips every 26 months, astronauts must wait for a return window, stretching round trips to nearly three years.

Souza's discovery changes that math entirely. By analyzing the asteroid's geometry during the October 2020 opposition, when Earth and Mars were closest together, he identified a route that could complete a round trip in just 153 days.

The timing matters. During a specific window in 2031, a spacecraft could depart Earth on April 20, reach Mars in 33 days, spend a month on the surface, and return home by September 20. The total journey would take roughly five months instead of three years.

The secret lies in data scientists usually throw away. Early asteroid observations are imprecise and get replaced as astronomers gather better measurements. Souza realized those initial, rough trajectories contain geometric clues that more accurate data obscures.

"Maybe I was in the right place at the right time," he said. Someone analyzing the same asteroid later wouldn't have seen the same path.

The speeds required are ambitious but achievable. The fastest route needs launch velocities around 27 kilometers per second, comparable to NASA's New Horizons probe, which holds the record as the fastest object ever launched from Earth. Next-generation rockets like SpaceX's Starship or Blue Origin's New Glenn could potentially reach those speeds.

Souza also identified a slower, lower-energy alternative requiring less fuel that would still complete the journey in about 226 days. That's roughly 7.5 months, still significantly faster than current timelines.

The Ripple Effect

Faster Mars trips mean more than just convenience. Shorter missions reduce astronaut exposure to cosmic radiation, one of the biggest health risks in deep space. They also cut the psychological strain of years-long isolation and reduce the amount of food, water, and life support systems spacecraft must carry.

The method works as a search tool too. Instead of calculating millions of possible routes, mission planners could use asteroid-inspired geometry to narrow options quickly. Future Mars oppositions in 2027 and 2029 didn't show the same favorable conditions, but 2031 does.

The concept remains theoretical and depends on spacecraft design, payload mass, and propulsion capabilities. But the math checks out, published in the journal Acta Astronautica in April 2025.

What started as an accidental observation while studying space rocks might just be the key to making Mars our neighbor instead of a distant dream.