NASA is sending a chopper to Mars.
Its next mission to the red planet is scheduled to launch in 2020, and will include not just another rover like Curiosity or Spirit, but an autonomous helicopter.
"NASA has a proud history of firsts," said NASA Administrator Jim Bridenstine. "The idea of a helicopter flying the skies of another planet is thrilling. The Mars Helicopter holds much promise for our future science, discovery, and exploration missions to Mars."
Planning for the helicopter mission began in 2013 at NASA's Jet Propulsion Laboratory (JPL). The result is a 1.8kg craft whose blades can spin 3000 times a second. That's about 10 times faster than one on Earth, speed needed to get lift in the thin Martian atmosphere.
"The atmosphere of Mars is only 1 percent that of Earth, so when our helicopter is on the Martian surface, it's already at the Earth equivalent of 100,000 feet up," said Mimi Aung, Mars Helicopter project manager at JPL.
"To make it fly at that low atmospheric density, we had to scrutinise everything, make it as light as possible while being as strong and as powerful as it can possibly be."
The helicopter will also have solar cells to charge its batteries and a heater to keep warm at night.
It won't be as easy as flying a drone, though.
"We don't have a pilot and Earth will be several light minutes away, so there is no way to joystick this mission in real time," said Ms Aung. "Instead, we have an autonomous capability that will be able to receive and interpret commands from the ground, and then fly the mission on its own."
If the chopper fails to take flight on Mars, the rest of the mission will go on unaffected. If it does, it'll be another milestone in the history of spaceflight.
"After the Wright Brothers proved 117 years ago that powered, sustained, and controlled flight was possible here on Earth, another group of American pioneers may prove the same can be done on another world," said Thomas Zurbuchen, associate administrator.
The helicopter and next rover are due to land on Mars in February 2021, seven months after leaving Earth.