What to expect from the spectacular Mars Perseverance landing on Thursday

Thursday is the big day. NASA’s multibillion-dollar Mars rover will arrive on the Red Planet and almost immediately begin the process of trying to land safely on the surface.

It’s easier said than done. As Mars approaches, the Perseverance rover will abandon its cruise stage, retaining only an aerosol spray for protection and a descent stage. This lightweight spacecraft will hit the atmosphere traveling at around 20,000 km / hour and will only have 410 seconds – or nearly seven minutes – to lose that speed and make a feathery touchdown.

How to land on Mars

Although the Martian atmosphere is thin, it will nonetheless provide the majority of resistance to slow down persistence. Within about 80 seconds of entering the Martian atmosphere, temperatures outside the hull are expected to reach 1,300 ° Celsius.

About four minutes after encountering the atmosphere, the vehicle’s parachutes will deploy. Shortly after, the protective aeroshell will fall, its job done. Then, when the vehicle descends approximately 4 km above the surface of the planet, it will activate its terrain navigation system. Until then, Perseverance’s journey will be very similar to that of the Curiosity rover, which suffered a similar “seven minutes of terror” on its successful landing in August 2012.

With Perseverance, there is one key difference: While Curiosity sought a safe landing site on the relatively smooth terrain of Gale Crater, this spacecraft will land in a more dangerous location with boulders, Jezero Crater. This location should allow a richer scientific exploration. To mitigate this risk, engineers added a new system to allow for a more precise landing.

As you descend, an on-board computer will quickly begin taking photos of the Martian surface, looking for features like craters, cliffs, and large boulders to compare with previously captured orbital images. Once the on-board computer has completed 15 landmark “matches”, it will switch to a higher resolution imaging mode to fine-tune the landing positioning. Curiosity could estimate where she was on Mars about 3 km away. Perseverance will reduce this error to 40 meters.

Upon reaching an altitude of 2 km, the rover will begin a motorized descent, followed by the “skycrane” maneuver to set Perseverance on Mars at a speed of less than 1 m / s.

When will we know Perseverance has done it? Onboard cameras will record its descent, but it will not be possible to relay this data in real time, and it will be sent a few days later. Since there is currently an 11-minute delay between Earth and Mars, we won’t know the fate of the spacecraft until after it lands (or leaves a smoking hole on the surface of Mars). Landing is scheduled for approximately 3:55 p.m. EST (8:55 p.m. UTC). With luck, a signal from the spacecraft will arrive on Earth, telling us that all is well.

NASA TV will provide live coverage on all regular locations starting at 2:15 p.m. EST (7:15 p.m. UTC) Thursday. So many people at NASA and in the industry have worked extremely hard to make Thursday a success, let’s hope they will be rewarded.

A very complex mission

Persistence has a lot in common with curiosity in other ways. They were built from the same design and share many common areas. But NASA learned from Curiosity about the vehicle’s performance on Mars – such as the need for more durable aluminum wheels – and because of that, NASA was able to push Perseverance further.

For example, scientists believe that the Jezero crater area was once a delta and ancient sediments have been preserved. Perseverance uses a laser spectroscopy system to search for past biosignatures.

The rover also contains a complex system that will collect and cache dozens of Martian rock samples in the hopes that a future NASA mission to Mars will retrieve those samples and bring them back to Earth. NASA and the European Space Agency are working on a joint mission that would return these rocks in 2031, but it is not fully funded.

Finally, of course, the Perseverance mission will bring the little one Ingenuity helicopter to the red planet. He will seek to demonstrate the first motorized flight on another world. It may not work – the Martian atmosphere is very thin, and so producing an elevator will be a challenge – but it’s great to see NASA taking risks like this that will only propel our space adventures to more. great heights.