For about a week in April, scientists at NASA’s Jet Propulsion Laboratory anxiously searched for signs of life on Mars.
Lost somewhere in the undulating terrain of a Martian riverbed was Ingenuity, the tiny, amazingly sturdy helicopter that had just completed its 49th flight on the Red Planet. The team searched every day for a radio signal that could confirm that the plane was OK.
Subscribe to The Post Most newsletter for the most important and interesting stories from The Washington Post.
On April 2, Ingenuity soared 16 meters into the air — a record height for the drone — to capture a suborbital image of the Martian landscape.
After landing it is gone. When scientists tried to upload instructions for another flight, Ingenuity’s radio signal was gone.
Scientists finally found Ingenuity after six days of searching when the helicopter’s companion on Mars, the Perseverance rover, climbed a ridge and drove closer to where the helicopter had landed.
NASA engineer Travis Brown described the episode in a blog post last week, offering a dramatic look at the agency’s exploration of Mars and the incredible resilience of the Ingenuity helicopter. Its hardiness continues to amaze NASA two years after scientists expected the tiny craft to break down.
The helicopter is flying again, Ingenuity team leader Teddy Tzanetos told The Washington Post, and its longevity has inspired the team to include helicopters modeled on it in a future Mars mission — a testament to how robust Ingenuity has proven itself.
“It’s absolutely ridiculous,” Tzanetos said. “This is something you only experience once in your life.”
Ingenuity defied the odds the day it first lifted off from Martian soil. The four-pound plane is about 7 inches long and is little more than a box of avionics with four spindly legs on one end and two rotor blades and a solar panel on the other. But it performed the first powered flight of an aircraft on another planet — what NASA called a “Wright Brothers Moment” — after arriving at Mars in April 2021.
Yet Ingenuity was never intended to be a proof-of-concept over $80 million. It hitchhiked to Mars on Perseverance, an SUV-sized rover that would carry out NASA’s planned mission to study the Martian soil.
Piloted by radio signals broadcast by Perseverance, Ingenuity completed its five-flight mission — a simple series to prove the helicopter’s design would work in the thin Martian atmosphere — in May 2021. Then Tzanetos’ team was cleared to keep flying.
“At that point we have borrowed time,” Tzanetos said. “None of the mechanisms are designed to survive longer.”
Somehow they did – months and months, and dozens more flights. In May 2022, it seemed that the wondrous story of Ingenuity would finally descend to (Martian) Earth. Winter was coming, and NASA feared the cooler temperatures would cause Ingenuity’s solar-charged batteries to fail or even freeze overnight.
The helicopter entered a low-power state after its 28th flight in late April of that year, and scientists told The Post they weren’t sure if it would fly again.
Incredibly, Ingenuity’s delicate parts withstood the cold of Mars. But NASA still faced the challenge of reconnecting to the helicopter every time the components jammed, Tzanetos said. The Ingenuity team adapted by using data from sunrises on Mars to calculate when the helicopter would defrost each morning and gain enough charge to power on.
The result? Playing a kind of hide and seek, where NASA sent Ingenuity on flights and then used its model to calculate when the helicopter would be back online to receive its next instructions. It was enough to get Ingenuity and her crafty mission team through the Martian winter.
“We still have to play some of these games now and then, depending on how cold it is or how windy it is at night,” Tzanetos said. “But the team has become very good at that.”
NASA began its most nerve-racking game of hide-and-seek with Ingenuity in April after Flight 49, when the helicopter accompanied Perseverance on bumpy terrain believed to be an ancient river delta.
Members of the team weren’t concerned when they couldn’t connect to the helicopter for the first few days after the flight, Brown wrote; their process sometimes took several days to find Ingenuity. But their fear grew as nearly a week passed. Tzanetos wondered if the brave helicopter’s luck had finally run out.
“Each [day] is a blessing” for ingenuity, Tzanetos said. “You are always prepared for the end of the mission.”
Finally, six Martian days after losing contact with Ingenuity, the team discovered a “single, lone” radio signal, Brown wrote. The next day, another signal appeared – confirmation that Ingenuity was alive. The team eventually concluded that a ledge had blocked the helicopter’s signals from reaching the rover.
Ingenuity again flew for the 50th time on April 13, soaring about 60 feet to break its altitude record once again.
Tzanetos said the team will continue to push the boundaries of Ingenuity. While Perseverance continues to collect soil samples from Mars, Ingenuity is free to roam the skies as a scout for the rover, collecting valuable data about the Red Planet and its own achievements as the first aircraft from Mars.
And Ingenuity probably won’t be the last. In 2028, NASA plans to send a lander to Mars to retrieve Perseverance’s collected samples. The craft would then launch from Mars — another astronomical first for the agency — and return the samples to Earth for study.
That mission has been redesigned in the wake of Ingenuity’s success, Tzanetos said. NASA now plans to send two helicopters of nearly identical design with the lander as backup to retrieve Perseverance’s samples in case the rover breaks down by the time the lander arrives in 2030.
It is unlikely that Ingenuity will still be flying by then. But for now, the brave helicopter refuses to die.
“If you had asked me two years ago what I hope will become of Ingenuity, I would have said, ‘Well, I hope our children or our grandchildren can build on this,'” Tzanetos said. “…Here we are, Ingenuity is still flying and designing the second generation.”
The Phoenix region cannot meet groundwater demand for the next century, threatening growth
How Michael Phelps learned to make the right decisions
A year after Uvalde, officers who failed their response have little consequence