The footage gave the world a glimpse of an often entirely invisible process, including the deployment of the parachute to slow the spacecraft after entering the atmosphere.
The 70.5-foot supersonic parachute was an extraordinary technical challenge, said Ian Clark, a systems engineer at NASA’s Jet Propulsion Laboratory in Pasadena, California. Clark, who has worked at JPL since 2009, has worked on the parachute for years. He conducted three tests on Earth to make sure the parachute could survive by inflating in a wind that would be twice the speed of sound, or Mach 2.
“We’ve done tests that haven’t really been done since the Viking program (in the ’70s and’ 80s), which involved testing supersonic parachute parachutes on a large scale,” Clark said.
Parachute tests were performed at NASA’s Wallops Flight Facility in Virginia in 2017 and 2018. The test team mimicked the Martian environment by using sounding rockets to reach half of the edge of space together. both the speed of sound and deploying the parachute.
Nylon, Technora and Kevlar were used to make the largest parachute ever sent to Mars, a material three times stronger than that used for the landing of the Curiosity rover in 2012.
The team felt confident in their tests, but it all depended on the primary performance of the parachute on Mars.
A secret code
Easter eggs are one of the missions NASA sends to Mars. For example, thanks to tiny holes in its wheels, the Curiosity rover – which explored Gale Crater – leaves “JPL” traces in Morse code as it moves through the Martian landscape.
While working on the design of the parachute, Clark knew that there would be a lot of use in creating a pattern. The patterns on the parachutes help indicate its orientation, how it inflates, and if there is any damage after inflation. Checkerboard patterns can be confusing, so Clark wanted to use something less uniform and more distinct.
Then Clark and some of his colleagues decided to have a little fun.
Clark is a puzzle enthusiast. He does the New York Times crossword puzzle every morning. His mother also saves the riddles from the Sunday edition in a kraft paper envelope which she gives to him each time he visits.
He thought of encoding words using binary code. But what would be the message? While he’s never been the type to look at a motivational poster and derive much meaning from it, three words stood out for Clark: “Dare the mighty things.”
The motto, taken from a speech by Theodore Roosevelt, can be found in the buildings of the JPL campus.
“Week after week, I never got tired of reading ‘Dare Mighty Things,” Clark said. “And that’s not just the sentence, but it’s even the larger context of the speech. This great inspiring message truly represented the culture of JPL and NASA as a whole. “
It also included the GPS coordinates of the JPL on the outer ring of the parachute.
At a press conference where the video was shared with the public on Monday, Entry, Descent and Landing Chief Allen Chen teased that there might be something to decipher in the parachute. orange and white.
Within hours, space fans began posting what they had deciphered to Reddit and Twitter. Clark was thrilled to see other people engage in this kind of puzzle solving, especially so quickly, as well as the joy that spread after the Mars video was shared.
Clark hopes the images and videos from Perseverance will inspire people and help them overcome the challenges of their time.
Inspiration becomes reality
Solar system exploration missions, such as Voyager, Galileo, and Cassini, have long inspired Clark.
As a child, Clark watched Carl Sagan’s “Cosmos”, the 1980 PBS show, recorded by his father. Clark watched as Sagan spoke about the billions of stars in the universe and shared the initial images returned by the Voyager probes as they flew to Jupiter and Neptune. This piqued his curiosity and made him want to get involved in aerospace engineering.
Even the smallest thing can damage the parachute “and ultimately lead to a bad day because of the chaos of the environment,” Clark said.
Wind moving in the wrong direction could have a catastrophic effect, causing the parachute to inflate upside down and destroy itself. Those who work on entry, descent and landing often point to the parachute as one of the aspects of a mission that scares them the most, as it is one of the least predictable of the mission. .
When Mohan said the parachute deployed, Clark kept an eye on the speed of the spacecraft as it descended into the atmosphere. At first it seemed a bit too fast, considering the distance between the rover and the ground.
But the parachute did its job, slowing the rover, and it landed smoothly in a perfect manner.
When footage and video of the descent began to return, Clark finally knew that the team’s efforts had paid off and the parachute had inflated beautifully.
“The realization of what happened started to come to the surface,” Clark said. “I said to the person who sent me the pictures, ‘I think for the first time today I feel happy.'”
With each mission, NASA builds on its past successes. This first video of a spacecraft landing on Mars will be used by teams planning other missions for decades, Clark said.
The importance of this type of footage cannot be overstated.
Some of the first parachute tests performed for a mission to Mars took place during the Viking program almost 50 years ago. Images from the tests on 16-millimeter film were believed to be lost to history, Clark said. But they were able to track it down to someone who donated it to a small museum in Bradenton, Florida.
Clark flew from Los Angeles to pick up the film and have it restored and digitized. Now the images are used to compare with their recent parachute tests.
Clark continues to work on the Perseverance mission in a number of ways. He was the project’s assistant systems engineer for sample cleanliness, making sure that the samples the Perseverance rover collects on Mars in its search for ancient life will not be contaminated with anything from Earth.
These samples will be returned to Earth in the 2030s by follow-up missions, called Mars Sample Return. Clark will be the phase leader of the mission that retrieves these samples from the surface of Mars and puts them back into orbit before they return to Earth.
“We’ve wanted to do this kind of mission for almost six decades now,” Clark said. “When we dare to do powerful things, we can actually achieve phenomenal success.”