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Big news from Mars this weekend. A small helicopter zipped around its surface, and as NPR's Geoff Brumfiel reports, it's exceeding all expectations.
GEOFF BRUMFIEL, BYLINE: The helicopter was carried to Mars on the much-larger Perseverence rover. So far, the rover's rolled a little over a mile, but the helicopter has gone further. It's whizzing ahead.
TEDDY TZANETOS: It is not a race, absolutely not a race.
BRUMFIEL: Teddy Tzanetos of NASA's Jet Propulsion Laboratory is the operations lead for the Mars helicopter, which is called Ingenuity. He's also an avid drone pilot.
TZANETOS: I love going out to a park and flying fixed-wing rotorcraft, helicopters, quads.
BRUMFIEL: But flying on Mars, Tzanetos will tell you, is a completely different ballgame. There are two big problems. First, the atmosphere is only about 1% of the atmosphere on Earth.
TZANETOS: To be able to fly in 1% of Earth's density, you need a vehicle that's very, very light.
BRUMFIEL: Second, it takes many minutes for a signal from a remote control on earth to reach a drone on Mars, so Ingenuity can't be remote controlled. It has to fly itself.
TZANETOS: Everything needs to be autonomous. The aircraft needs to be able to control itself, respond to wind gusts, respond to changes in how the aircraft itself is performing.
BRUMFIEL: And that's a big part of why nobody has flown around on Mars before - because in the past, the computers and cameras a drone would need for autopilot just weighed too much. Ingenuity has solved that problem, though, using some super-lightweight microchips.
TZANETOS: We are using some of the most powerful computers we've ever sent out into space. And that just happens to be a cellphone processor from a couple of generations back.
BRUMFIEL: That's right. Cellphone processors like the ones in your pocket right now are flying a drone on Mars, and it is flying. In August Ingenuity flitted across a group of sand dunes in an area of Mars known as Seitah. It was terrain the Perseverence rover couldn't drive through.
TZANETOS: They've got a very long distance to get around the bottom of Seitah. And they're coming on their way now north.
BRUMFIEL: I know you said it isn't a race, but you won. You got there first, didn't you?
TZANETOS: (Laughter) No, no, there's not a race. So, I mean, we got - you know, we are the forward scout.
BRUMFIEL: Scouting the ground for Perseverance is a big part of Ingenuity's mission. That's in part because the little helicopter's just a test vehicle. It's not designed for scientific research. Tzanetos thinks that will change in the future, though. Drones will become valuable explorers.
TZANETOS: A rotorcraft can fly up to a cliffside wall and take images of a cliff. We can dive into caves. Having that completely brand-new perspective is something that we think is going to blow the doors open on exploration of Mars.
BRUMFIEL: And it's not just Mars. NASA's working on a giant drone to explore Saturn's moon Titan. The thing is the size of a small car. And if you're wondering how that's going to work, well, Elizabeth Turtle, the principal investigator of the Titan mission, says it turns out the moon is a perfect place to fly. It's got a thick atmosphere and not a lot of gravity.
ELIZABETH TURTLE: So physically, it's actually easier to fly on Titan than it is on Earth.
BRUMFIEL: Turtle and the rest of her team are closely watching Ingenuity's progress. It's a chance for them to learn about flying on other worlds. But also, she says, it's cool.
TURTLE: It's just really exciting, you know, to see a vehicle flying on another planet.
BRUMFIEL: Although Ingenuity isn't flying right this second, it's sitting on the surface of Mars, waiting for the Perseverence rover to catch up. But, again, it's not a race.
Geoff Brumfiel, NPR News.
(SOUNDBITE OF AU REVOIR SIMONE SONG, "KNIGHT OF WANDS") Transcript provided by NPR, Copyright NPR.
