When it comes to exploring Mars, human-made robots have, literally and figuratively, only scratched the surface. To date, rovers on Mars have driven less than 40 miles on the Red Planet. The surface of Mars is almost 56 million square miles, and while satellites orbiting the planet like the Mars Reconnaissance Orbiter have helped, there is still a lot of ground left to cover up close. One faster way to do that is a plane, and NASA has a concept for a Martian flyer that might work.
Meet the awkwardly named Prandtl-m, short for “Preliminary Research Aerodynamic Design to Land on Mars.” (The name is a tribute to German aerodynamicist Ludwig Prandtl). Getting it to Mars is years away, so there’s plenty of time to come up with a better name for a Mars-bound version. Humans are really good at figuring out how to fly on earth, so this preliminary research plane will tackle a major challenge for any extra-terrestrial airplane: how to fly in thinner air with less gravity on a different world.
NASA’s considered Martian planes before, and it looks like Prandtl-m has at least some passing similarity to the earlier, proposed “Aerial Regional-scale Environmental Survey of Mars” (ARES) plane, which clearly used up the good acronym. Both ARES and the Prandtl-m are mostly flying wing, with a large thin body to maximize lift generation. To replicate the thin Martian air for the Prandtl-m, NASA will lift their plane by balloon to 100,000 feet, and then release it.
The tiny, unmanned drone will weigh 2.6 pound on earth, or just about one pound in Martian gravity, assuming it ever gets there. The initial launch will see how well Prandtl-m can fly. On subsequent launches, Prandtl-m may carry small payloads, like mapping cameras or sensors that record radiation. To truly replicate the experience of falling into the Martian atmosphere, a third launch would release the drone from 450,000 feet above Earth itself, allowing the future martian to glide its way into the atmosphere.
Some day, drones like the Prandtl-m may explore Mars itself, adding aerial robots to the planet’s slow-growing fleet of rovers and keeping the Red Planet a robot planet for a while longer — at least until humans follow suit.