“Success is never assured, and that's especially true when we're trying to land the biggest, heaviest, and most complicated rover we've ever built to the most dangerous site you've ever attempted to land at.”

Science

To survive Mars, Silicon Valley’s favorite car tech will guide Perseverance

Self driving technology

by JoAnna Wendel

On February 18, Mars Perseverance Rover will touch down on the Red Planet and embark on an ambitious search for signs of extraterrestrial life. As it trundles across Mars' surface, it’ll cache samples of Martian rock and soil in special containers — all in the hope that someday, a future (likely also a robot) explorer will bring this precious dust back to Earth. But that's if the rover ever reaches Mars, of course.

The countdown of less than 30 days till Perseverance lands at Mars' Jezero Crater has begun. At a press conference on Wednesday, January 27 to mark the milestone, NASA scientists went over the final preparation stages for the mission, which is currently hurtling toward Mars at nearly 25,000 miles per hour.

READ MORE PERSEVERANCE ROVER NEWS FROM INVERSE

NASA’s Mars 2020 spacecraft carrying the Perseverance rover as it approaches Mars.

NASA/JPL-Caltech

“Entry, descent, and landing is the most critical and most dangerous part of the mission,” Allen Chen, the lead scientist on the entry, descent, and landing for Mars Perseverance at NASA’s Jet Propulsion Laboratory said a the event.

“Success is never assured, and that's especially true when we're trying to land the biggest, heaviest, and most complicated rover we've ever built to the most dangerous site you've ever attempted to land that.”

Where will Perseverance Rover land on Mars?

Perseverance’s landing site, Jezero Crater, is a 28-mile-wide impact crater just north of the Martian equator.

Scientists chose this landing site because of ancient remnants of what looks looks like a river delta — a fan-shaped structure which forms when a river empties into a large body of water. Scientists also know Jezero Crater once contained a lake. Perseverance’s main mission is to answer one, deceptively simple, question: Did life ever exist on Mars?

How will Perseverance Rover land safely on Mars?

Right now, Perseverance is traveling towards Mars at a fantastic speed — going some 600,000 miles distance every day. For context, that is as if it were zipping around the Earth some 25 times each day. On February 18, NASA will instruct the craft carrying the rover to drop into the Martian atmosphere at 12,000 miles per hour. As it plunges towards the surface of the planet, a (very strong) parachute will deploy, allowing the precious robot cargo to float gently down at a far slower 2 miles per hour.

Hundreds of critical events must execute perfectly and exactly on time for the rover to land safely on Feb. 18, 2021.

NASA/JPL-Caltech

Then, the rover will be lowered via sky crane, a technology first used to gently place NASA’s Curiosity on Mars’s surface in 2012. Once Perseverance touches down, the sky crane will fly off automatically to crash-land itself — talk about taking one for the team.

And once Perseverance passes the landing milestone, that’s when the real fun begins.

Well, sort of.

What happens after Perseverance Rover lands?

According to NASA, the first thing scientists on the ground need to do is to make sure everything on the rover survived the journey and is functioning properly. If all systems are go then, the rover will deploy the Ingenuity helicopter, which will hopefully become the first free-flying vehicle to ever zip about another planet.

NASA's Ingenuity Mars Helicopter flying through the Red Planet's skies.

NASA/JPL-Caltech

That's when the real fun begins.

“What we're going to do as soon as we get [to Mars], is to explore the rocks that were deposited in that lake for biosignatures for evidence of ancient life,” Ken Farley, Perseverance’s project scientist and W.M. Keck Foundation Professor of Geochemistry at CalTech, said at the same press conference.

What Farley means is that much of the rover’s job will be to look at rocks for evidence of biological structures like stromatolites — leftover signs of ancient microbial life. Perseverance will also use its onboard science tools to disintegrate rocks to study their chemical components.

Made from fossilized microbes and sediment, these rounded rocks are stromatolites found in a dry lakebed during a field exercise in Nevada. Scientists hope to find something similar in the dry lakebed Perseverance will be exploring on Mars.

NASA/JPL-Caltech

How will NASA control Perseverance on Mars?

Because Mars is so far away from Earth — 128 million miles at its closest — radio instructions from Earth can take up to 22 minutes to reach rovers on Mars, and vice versa. So scientists need their rovers to be as self-sufficient as possible. To ensure that, they turn to a technology much touted as the future of driving on Earth: Autonomous Navigation, aka, self-driving technology.

Self-driving technology is a familiar concept to those of us who follow Tesla and other proponents of this tech, like Apple. The way it would work on Mars follows the same logic as here on Earth: The car, or rover, uses cameras to identify hazards and make split-second decisions about how to drive safely past them, or choose a new, safer route.

When NASA’s other operating rover, Curiosity, is in ‘AutoNav’ or self-driving mode, it uses instructions sent from scientists on Earth to head to a destination. As it goes it takes pictures of its surroundings, enabling its onboard computer to spot hazards and autonomously choose safe routes.

But the way this plays out on Mars speaks to why self-driving technology is perhaps still a long way off here on Earth. Curiosity has to stop every three feet or so to take pictures of its surroundings in order to identify any areas of especially loose material or big rocks — anything that might hinder its wheels. This means Curiosity can only move about 100 feet in an hour, according to a Medium post written by rover-driver and mechanical engineer Evan Hilgemann, who works at NASA’s Jet Propulsion Laboratory.

This annotated mosaic depicts a possible route the Mars 2020 Perseverance rover could take across Jezero Crater.

NASA/JPL-Caltech

Perseverance will go a little faster than Curiosity. According to Hilgemann, Perseverance’s navigational cameras will take higher resolution photos, as well as color photos, helping the rover detect hazards more efficiently and accurately. Perseverance also packs a second computer to help it navigate, according to Wired. It’ll also use stereo vision to help it see its surroundings more clearly, plus new-and-improved algorithms to help it navigate the difficult Martian terrain with more speed and confidence. In the end, Perseverance will be able to drive up to about 650 feet per day — three times faster than Curiosity.

Still, this is hardly the high speeds promised by Tesla and others for their self-driving cars here on Earth. The rovers' slow speeds reveal why such technology is just so hard to put into place here — on Mars, the only hazards are geographical. On Earth, you need to account for humans and all of their unpredictability, too.

The initial trail outlined for Perseverance measures 15 miles — including a climb up a crater rim thousands of feet high. It will take years to traverse this distance, Farley said. But this short stretch will reveal parts of Mars never seen up close by humans, and, just maybe, that Earthlings aren’t the only life in the solar system.

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