As NASA’s Mars 2020 Rover is prepping for its upcoming interplanetary journey, it’s harboring a stowaway. An experimental helicopter is coming along. Engineers at NASA’s Jet Propulsion Lab in Pasadena, California, attached the twin-rotor, solar-powered helicopter to Rover’s underbelly in late August. They say it will be the first aircraft to fly on another planet.
The Mars Helicopter is completely encapsulated to protect it from debris during entry, descent, and landing. Once on the dusty surface, it will deploy for test flights near the Jezero Crater. On this trip, the helicopter won’t be used for collecting data. That way, if there are glitches or malfunctions, the Mars 2020 mission won’t be impacted. But if it does take flight as designed, future Mars missions could enlist second-generation models of the helicopter to add an aerial dimension to their explorations.
But how does it work? Helicopters achieve lift by pushing air downward as the blades of the rotors spin. That creates pressure which raises the copter up—on Earth, that is, where God provided a dense atmosphere to harness with those blades. Mars has barely any atmosphere in comparison—only about 1% of the density of that on Earth. There’s not much air there for the blades to push against. That means the Mars Helicopter will have to work a lot harder than earthly whirlybirds.
The rotors on the Mars Helicopter spin between 2,400 and 2,900 rpm (revolutions per minute—think about that speed!). That’s about 10 times faster than a helicopter operating in our home atmosphere. But it will take that much constant rotation to move enough Martian air over the blades to create lift.
Once aloft, the helicopter will fly on its own. It won’t have input from controllers millions of miles away back at home. The entire purpose of this little craft is to prove that powered flight on Mars is possible.
But after that is achieved, NASA scientists imagine all that helicopters might do there one day. They envision space choppers investigating difficult-to-reach destinations on the rocky Red Planet such as cliffs, caves, and deep craters. The craft could carry small science instruments or act as scouts for future human and robotic explorers. The idea that soon “the sky’s the limit” on another planet is truly “out of this world”!