terrestrial sky | Crash-landed on Mars… on purpose

As we know, landing on Mars is difficult. Many landing attempts over decades failed, and the lander sadly crashed into the desert surface of Mars. Sure touchdowns are now more of the norm (albeit still delicate). But what if you searched crashing into Mars… on purpose? NASA said last week (October 20, 2022) that it was testing a new type of lander — dubbed SHIELD — that would land on purpose.

The thought is that the easiest way to land on Mars is to just crash, but with a lander designed to survive a hard impact.

Crash landing on Mars

Why is it so hard to land on Mars? The reason is the thin atmosphere of Mars. Lander and Rover had to use giant parachutes, airbags and jetpack-style aerial cranes to land as gently as possible. But NASA’s latest concept, the Simplified High Impact Energy Landing Device (SHIELD), would dispense with those technologies.

Instead, SHIELD would use an accordion-like collapsible damper base on the lander. It looks like an inverted pyramid made of metal rings.

The base would act like a car’s crumple zone, absorbing the impact.

Cost reduction and new landing pads

A key benefit of using SHIELD would be cost reduction. Mars missions are very expensive to launch, land and then maintain on the surface. SHIELD would greatly simplify the landing process and reduce costs. Also, out of necessity, missions to the Martian surface have landed in locations with relatively few craters or large rocks. A crash landing would result in Mars spacecraft landing in riskier areas. Lou Giersch of NASA’s Jet Propulsion Laboratory (JPL) said:

We think we could go into more treacherous territory where we don’t want to risk deploying a multi-billion dollar rover with our current landing systems. Maybe we could even land several of these in different hard-to-reach places to build a network.

Crash landing on Mars… and on Earth

NASA makes an interesting comparison to support their SHIELD concept. When the first Mars samples are eventually returned to Earth, they will be in a capsule that is scheduled to land on Earth’s surface, likely in a desert region. If we can do that, why not explore crash landings on Mars? As Velibor Cormarkovik, part of the SHIELD team, noted:

If you want to land something hard on Earth, why can’t you do it the other way around on Mars? And if we can pull off a hard landing on Mars, we know SHIELD could work on planets or moons with denser atmospheres.

The same technique was used for samples returned to Earth from asteroids and comets.

protection of the lander

Of course, during the crash landing, NASA wants the lander itself to survive the impact. So in 2022, the team tested the concept with a drop tower at JPL in Pasadena, California. The test involved similar sample tubes to those used by the Perseverance rover to collect its samples for later return to Earth. Could the sample tubes survive a crash? The almost 27 meter high drop tower throws objects onto the earth’s surface at a speed similar to a crash landing on Mars. The technique is similar to the way cars are tested on Earth using crash test dummies on sleds. Cormarkovik said:

The tests we ran for SHIELD are somewhat of a vertical version of the sled tests. But instead of a wall, the sudden stop is due to an impact into the ground.

It worked!

The test lasted only two seconds. And success! The collapsible attenuator included a smartphone, radio, and accelerometer. After SHIELD climbed to the top of the tower, the countdown began. Nathan Barba, another member of the SHIELD project, said:

I got goose bumps when I heard the countdown. The entire team was curious to see if the objects inside the prototype would survive the impact.

SHIELD hit the ground at about 110 miles (177 km) per hour, the same speed a lander normally travels as it approaches the surface of Mars. It hit with a force of about 1 million Newtons, which is about 112 tons.

In this test, SHIELD crashed into a 5 cm thick steel plate. This mimicked a harder landing on Mars. In previous tests, SHIELD had crashed into dirt. Interestingly, SHIELD bounced about 3.5 feet (about a meter) after impact. The SHIELD team say this is likely due to the steel plate, as there was no bounce in previous testing.

The phone and other equipment on board all survived the impact. This is good news for future testing and the concept as a whole. The SHIELD team was quite happy with the results. Giersch said:

The only hardware that suffered damage were some plastic components, which we weren’t worried about. Overall, this test was a complete success!

Conclusion: NASA has successfully tested a new Mars lander concept called SHIELD, specifically designed for intentional crash-landing on Mars.

About Jet Propulsion Laboratory