The Séítah region on Mars, filled with rocks and sand dunes, was too treacherous for NASA’s Perseverance rover to drive across. So Ingenuity, the tiny helicopter accompanying the rover, flew over the area on Monday and snapped some photos of a key spot on the other side. In less than three minutes, Ingenuity spared Perseverance the months it would have had to spend driving to take its own photos.
The quick Monday morning jump across Séítah was Ingenuity’s ninth flight on Mars so far, but it marked the first time the chopper lent a helping hand to Perseverance in its hunt for ancient signs of life at the Red Planet’s Jezero Crater. The four-pound helicopter arrived on Mars on February 14th, attached to Perseverance’s underside, and became the first object to take powered flight on another world on April 19th. Its initial set of flights served as increasingly complex practice tests to demonstrate how off-world rotorcraft can buzz around places that wheeled rovers can’t go.
“This was a big leap — big leap — in terms of what we’ve done before.”
But on Monday, NASA engineers pushed Ingenuity’s limits further than ever. In 166 seconds, Ingenuity flew roughly 11mph for almost a half-mile, or 2,050 feet — a far greater distance than its most recent flight in June, which tallied 525 feet. The copter buzzed around different corners of Séítah and snapped photos of its borders, where junctures between different rock formations — called contacts, in geology lingo — make for some of the most scientifically intriguing targets in Perseverance’s hunt for fossilized microbial life.
“This was a big leap — big leap — in terms of what we’ve done before. We went between sites that were 620, 625 meters apart, which is enormous compared to what we’ve done before,” Ingenuity chief pilot Harvard Grip said in an interview. Ingenuity’s photos, expected in the coming days after traveling down a delayed Mars-to-Earth data pipeline, will help engineers at NASA’s Jet Propulsion Laboratory decide whether to send Perseverance on a path to scoop up rock samples in that particular contact region.
The mission is “designed to be high risk, high reward, so that means it makes sense for us to take those additional risks because of the potential payoff,” Grip said.
Ingenuity, originally designed to fly on short trips from point A to B, dipped into one of Séítah’s eroded craters, slowed its speed, then ascended up slopes for the first time while dancing along a zig-zagged path. Its autonomous navigation algorithms were written to anticipate flying over only flat terrain, so engineers tweaked the code and convinced the helicopter that Séítah’s bumpy features were flat. That demanded several simulations in preparation for the flight, mainly to predict whether the helicopter could potentially spin out of control under its new flight directions. No accidents occurred, and Ingenuity successfully reached the targeted rock formation on the other side of Séítah.
“Let’s go big, and let’s take a risk and get across Séítah”
“This was the first time where we really said, ‘Let’s go big, and let’s take a risk and get across Séítah,’ which we know is an extremely challenging terrain for a rover to traverse,” Ken Williford, deputy project scientist for the Perseverance mission, said in an interview.
Sending a tiny drone across a potentially dangerous field of thick sand to scout for cool Mars rocks is a huge time-saver for the Perseverance team. “When scientists can get those images of that contact early, we can start the science process much earlier than we would otherwise, and start to make observations and interpretations and understand what those rocks are,” Williford says.
The rover has its own cameras, primarily designed to analyze nearby rocks and Martian landscapes. And sensors aboard NASA’s Mars Reconnaissance Orbiter, a satellite roughly 155 miles above Mars’ surface, give the Perseverance team imagery of far-off rock targets but lack the close-up details a helicopter like Ingenuity can provide.
The helicopter was set for retirement after its first five flight demonstrations to let the Perseverance team focus on its own work. But after Ingenuity aced its fourth flight in late April, engineers decided to expand the craft’s mission on Mars to demonstrate how helicopters could help future rovers conduct science. Some of Ingenuity’s midflight photos taken during test flights were convenient for Perseverance scientists, but Monday’s flight marked the first time that it took off with a sole mission to help the rover’s science team.
“A very unique interaction” between Perseverance and Ingenuity teams
NASA leadership approved Ingenuity’s mission expansion on the condition that it doesn’t perturb or interfere with Perseverance’s core mission, Williford said. A small “interface” team combining engineers from Perseverance and Ingenuity, serving as the operational glue between the two missions, has since been expanded to include Perseverance scientists as Ingenuity proves itself more scientifically useful than expected. For most NASA missions, these interface teams sometimes spark debate and disagreement as eager scientists negotiate technical risks with more risk-averse spacecraft engineers. But the Ingenuity-Perseverance team is surprisingly smooth, Williford says.
“This has been a very unique interaction, where I can go in there and say, ‘You know what would be so fantastic? Is if we could get over here,’ and then to hear Bob Balaram [Ingenuity’s chief engineer] say, ‘Yeah, let’s do it!’ and really pushing his team to go further,” said Williford, who also works as the director of JPL’s Astrobiogeochemistry Laboratory. “It’s been one of the most fun things that I’ve ever done, really. Working with those engineers and a few other scientists to plan these flights, I feel like a 12-year-old kid again, honestly.”