Tuesday , June 28 2022

InSight Journal: Knocking the land and landing on Mars


Artwork: InSight landerCopyright Protection

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Artwork: It takes 6.5 minutes to move from the top of the atmosphere to the surface

Prof. Tom Pike from Imperial College London is part of Mars's US-led InSight mission team. His group provided small seismometers that would allow NASA to detect "Marsquakes," which should show us the internal structure of the Red Planet. Here, just a few hours before InSight's bid to reach the surface of Mars, Prof. Pike reveals his feelings.

As a scientist, it seems difficult for me to think that the chance could play a role in making progress.

Napoleon must have asked, "I know he's a good general, but is he lucky?"

Any scientist would change their minds if they thought they would be similarly interrogated.

As for the engineers, it would have been an insult if their bridges or tunnels had to rely on luck not to collapse or sink.

However, as we now expect InSight to reach the peak of Mars' atmosphere, I hope to have some luck.

InSight: Mission from the heart of Mars

Surely it should not be an insult! We have some of the best engineers in the world from the NASA Jet Propulsion Laboratory to land our instruments on Mars.

Given that, overall, about 60% of the missions launched on Mars are failing, they have an amazing record.

The last seven JPL missions have sent Red Planet, Odyssey Orbiter, Spirit Spirit and Opportunity, Mars Reconnaissance Orbiter, Phoenix, and Curiosity Rover – all these missions have done.

Six years ago, Curiosity was lowered to the Martian surface from the unlikely "skycrane," an astonishing piece of engineering. We do not want the JPL to break the winning line now!

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Artwork: A "Skycrane" was used to put Curiosity on the surface

But even the best engineers in the world can not control all the risks InSight faces within a few hours, descending on the surface of the planet. There are a number of spacecraft operations that have to be executed erroneously, but even then, we could get to land in a wrong place.

A rocky landing?

Mars is a rocky planet. Without any rain, only the wind will slowly break the rocks that sink the surface. And the rocks are continuously eliminated on the surface as meteorites hit the mild atmosphere of Mars for billions of years and redo the surface.

If we go back to a big boulder, we risk losing a foot or putting the deck on the ground.

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T.Pike / Imperial College London

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Constantinos and Alex from the British team take into consideration InSight's chances to show up before landing

This is a game of luck – how much do we need luck? Constantinos Charalambous, one of our team members in the UK, works with Matt Golombek and JPL scientists to calculate these odds.

This is not simple. The best images we have about our landing area can see rocks up to one meter in diameter. But the rocks of less than half of this size could kill our mission.

We had to choose a peering site based on peering under our resolution, using the best statistics we can throw on this issue. Constantinos wrote his doctoral thesis on this issue, based on the data from the 2007/8 Phoenix mission on Mars.

The Phoenix Microscope Station has given us the closest look I have ever had to the Martian soil. Constantinos worked back from those images to fill the way the stones on Mars broke from huge boulders a few yards to the finest dust invisible to the first man who set foot on the planet.

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NASA / JPL-Caltech / University of Arizona / University

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Dust Phoenix data has helped us reliably calculate the chances of safe landing of InSight

Based on these calculations for the area we chose to land on InSight, we think the chances of getting down on a too big stone are 3%. This is certainly not impossible, and JPL has hit the best chances in the past.

But it is fair to say that they have guided their luck, and not every mission has the same fortune.

For example, it seems that Beagle II, the first and only attempt to land on Mars, had the misfortune to come down near a boulder that prevented them from unpacking their petals to gain power and send a signal to Earth.

Crossed fingers

It's not just stones. The Mars atmosphere varies wildly and we rely on it to slow down. The European Spatial Agency's Schiaparelli mission, the last landing attempt on Mars, failed when it began to rotate too quickly under its parachute on the road.

Although I do not want to admit this, we need some luck on Monday. As Napoleon said, "The greatest events hang on a thread."

I hope the thread is strong enough to reach Mars in one piece.

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