Nasa is getting ready to fly a helicopter on Mars for the very first time.
The space agency plans to launch a small chopper named Ingenuity on Sunday to test whether these kinds of crafts can fly on the Red Planet.
The helicopter travelled to Mars inside the belly of the Perseverance rover, which touched down on the planet in February.
Mars has an extremely thin atmosphere, so engineers have made the helicopter very light at roughly 1.8 kg (4 lbs) in mass. It also has large blades that spin very quickly.
Mars’ weak gravity should make life a little easier for the chopper. The planet experiences about a third of gravitional pull felt on Earth.
Ground-based flight controllers can’t direct Ingenuity in real-time, so the clever craft has been programmed to make some of its own decisions.
The chopper will use temperature readings and other sensor data, as well as images of terrain, to stay on its programmed flight path.
Livestream from mission control
A livestream confirming the helicopter’s inaugural flight should begin at about 8.30am BST on Monday.
Mars fans will be able to watch the stream on Nasa TV, the space agency’s app and on social media platforms including Youtube and Facebook.
A post-flight briefing from mission control is slated to begin at 4pm BST.
The date and time of the streams may change as engineers perform pre-flight checks of the helicopter and the rover.
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Nasa hopes Ingenuity will lay groundwork for robotic flying vehicles that could one day be part of human missions to Mars.
If all goes ahead as planned, the helicopter will fly on the eve of the 60th anniversary of the first human space flight.
Russian cosmonaut Yuri Gagarin completed one orbit of the earth after being blasted into space on April 12 1961.
Exactly 20 years later to the day, the US launched its first Space Shuttle mission.