CAPE CANAVERAL, Florida -- NASA's attempt to launch the first powered, controlled flight on another planet set for this weekend has been delayed for a few days.
The 4-pound helicopter, named Ingenuity, will attempt to rise 10 feet into the extremely thin Martian air on its first hop. Up to five increasingly higher and longer flights are planned over the course of a month.
The space agency is targeting some time beginning April 14, according to officials. The launch had been planned for Sunday night, but issues came up during a high-speed rotor spin test.
Once it happens, it will mark a "Wright brothers' moment," noted Bobby Braun, director for planetary science at NASA's Jet Propulsion Laboratory.
Ingenuity hitched a ride to the red planet with the Perseverance rover, arriving in February.
The helicopter airfield is right next to the rover's landing site in Jezero Crater. The rover will observe the test flights from a distant perch before driving away to pursue its own mission: hunting for signs of ancient Martian life.
Designers had to figure out how to keep the helicopter light enough to go to Mars but sturdy enough to survive the conditions there. One of the features includes Styrofoam inside the blades. Ingenuity will receive data instructing it to fly from Mission Control at NASA's Jet Propulsion Laboratory.
Flying on Mars isn't easy: the atmosphere is thin (about 1% the density of Earth's atmosphere). Ingenuity has to spin its blades much faster than at Earth to get enough lift and be very light (about 4 pounds or 1.8 kg).
In honor of the other historic flights Ingenuity is carrying a piece of the original Wright Brothers plane.
The Associated Press contributed to this report.