BBC shares a video showing how February’s Perseverance Mars rover mission plans to start with an automated landing sequence engineers have dubbed “the seven minutes of terror”:
The robot is being sent to a crater called Jezero where it will search for evidence of past life. But to undertake this science, it must first touch down softly.
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It starts more than 100km above Mars where the Perseverance rover will encounter the first wisps of atmosphere.
At this point, the vehicle, in its protective capsule, is travelling at 20,000km/h (12,000mph).
In little more than 400 seconds, the descent system has to reduce this velocity to less than 1m/s at the surface.
Most of the work is done by a heat shield.
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At an altitude of 2km, and while moving at 100m/s – the Perseverance rover and its “Skycrane” separate from the backshell and fall away.
Eight rockets then ignite on the cradle to bring the rover into a hovering position just above the surface. Nylon cords are used to lower the multi-billion-dollar wheeled vehicle to the ground.
But that’s still not quite it.
When Perseverance senses contact, it must immediately sever the cables or it will be dragged behind the crane as the cradle flies away to dispose of itself at a safe distance.
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It’s worth remembering that on the day of landing, the time it takes for a radio signal to reach Earth from Mars will be roughly 700 seconds.
This means that when Nasa receives the message from Perseverance that it has engaged the top of the atmosphere, the mission will already have been dead or alive on planet’s surface for several minutes.