23 Perseverance
For heading back to Mars—helicopter in tow
Seeking to definitively answer the question of whether there was ever life on Mars, NASA launched the US$2.4-billion Perseverance robotic rover. After blasting off 30 July 2020 from Cape Canaveral Space Force Station, it finally landed on the red planet in February. But the journey from concept to reality was fraught with risk—not only did a pandemic thrust much of the U.S. space agency team into remote work overnight, but the team had to navigate a first-of-its-kind technology, as well as the sheer complexity of the project. Entry, descent and landing are often dubbed the “seven minutes of terror” because of the precision required—and Perseverance was headed to “the most challenging Martian terrain ever targeted,” according to NASA. At the same time, the mission’s launch period was hard and fast: missing it would mean waiting another 26 months for the right planetary alignment.
“The pressure surrounding a Mars launch is almost beyond believable,” says Jennifer Trosper, project manager for the Perseverance mission. “No matter how hard we try, we almost always underestimate the time it takes to do something of this level of complexity. So the schedule is of the utmost importance to the management team.”
With a strong focus on managing and mitigating risks, the team made sure that pricey two-year delay never happened.
Riding on top of an Atlas V-541 rocket, the Perseverance rover landed safely—and now even has its own Twitter feed (Hobbies: photography, collecting rocks, off-roading.) Its aim is to look for signs of ancient microbial life, collecting rock and soil samples that can be collected by a future mission that will return them to Earth for analysis. On its belly is Ingenuity Mars Helicopter, which since April 2021 has been busy making the first-ever powered, controlled flights outside of Earth, testing out how an aerial reconnaissance vehicle might be able to help future missions and the Perseverance rover team.
Collecting geological samples and getting them back to Earth could “provide the best chance of answering these big science questions, specifically, could there have potentially been life in the ancient past on Mars?” says George Tahu, NASA’s program executive for the Mars 2020 mission. “That’s the big one. But we also have other questions about the history and evolution of the planet from a geology standpoint, the history and current nature of the climate, and also, how can we best prepare for future human exploration?”
The Power of Good Enough
NASA spent roughly US$2.4-billion to build and launch Perseverance, and project leaders knew they had to make the most of that budget, while still going in with a controlled vision.
“You don’t get an opportunity to go to Mars that often and there can be some really compelling ideas out there, but you can’t do everything,” says Tahu. “You have to really work through what the real objectives are and what’s most feasible with acceptable risks. You may have a brand-new instrument proposal that promises a lot of great new measurements, but it’s never been built before or may have a higher risk. You have to make those trade-offs.”
Perseverance’s engineering design is based on Curiosity, which landed on Mars in 2012—but the team added some souped-up features. The rover’s autonomous capabilities have been vastly improved, and in preparation for future human missions, MOXIE (the Mars Oxygen In-Situ Resource Utilization Experiment) is testing the ability to make oxygen from the tiny amount of carbon dioxide in the red planet’s atmosphere.
Like any organization, NASA’s budgets and timescales are finite, so the team worked through how much time to spend when—inevitably—issues arose. For example, deep into the project, a problem was detected during a test of one of the arms. The flight unit was sealed within Perseverance. But accessing it and taking it out to inspect might have jeopardized the whole mission.
“We had to kick off a bunch of parallel activities to understand whether it was because the test itself was flawed, or the hardware was flawed because there was something we didn’t understand about the design,” says Trosper. “In the end we convinced ourselves that we could avoid the problem if we operated the flight arm at a higher temperature on Mars, making it good to go for launch. You just have to make a call based on the data and experience you have.”
Leading Through Uncertainty
Working out of NASA’s Jet Propulsion Laboratory, Trosper has been part of the Perseverance team for eight years, taking on a variety of roles, which she says has given her better insight into what happens on the ground. “I know all the pieces and also how things are put together, which makes it easier for me to be more effective in helping folks when they may have problems or need guidance on a difficult situation, because I’ve been in their shoes.”
The pandemic shook that confidence to the core. Suddenly, the many teams that Trosper oversees—engineering operations, robotics operations, instruments and science operations—were faced with strict lockdown requirements, just a few months before the launch deadline. Most of the rover was already in Florida, largely built and getting ready to integrate into the launch rocket. But the team had to complete critical prelaunch tests and a significant set of work required for landing and the surface mission, while learning a completely new way to work together.
“A lot of what we do is highly collaborative, with someone showing you something, or you’re peering at someone else’s monitor,” she says. “Suddenly, we had to work remotely and still have everybody be part of the conversation, even if they weren’t in the room.”
Some staff flew back and forth to Florida to complete the vehicle preparations for launch. Meanwhile Trosper worked on a triage system that would determine what final prelaunch testing needed to be done and what could be deferred until after launch or even after Perseverance landed safely on Mars.
When launch time finally arrived, “I remember I showed up for work that day thinking: How can so much be resting on this one day?” she says.
But the curveballs didn’t stop at launch.
The team had settled on Mars’ Jezero crater as a landing site, because scientists know it once held water (and therefore life), making it a great spot for collecting telling rock samples. However, in early August, Perseverance’s first soil-sampling attempt failed. The rock targeted was deemed too crumbly, returning an empty test tube to the cache rather than an in-tact core, something that had never happened when the team tested the system on Earth.
Second and third sampling attempts, in September, went far better. With a sampling and caching system that uses more than 3,000 individual parts, the Perseverance rover took the first sample of Martian rock, a core slightly thicker than a pencil, from the Jezero crater. The samples, hermetically sealed inside their container tubes, are now candidates for NASA and the European Space Agency’s Mars Sample Return campaign.
Perseverance is currently exploring South Seítah, a geologic unit within Jezero crater filled with sand dunes, intriguing ridges, rocky outcrops and boulders.
Analyzing those results may take years, but could unlock untold secrets.
“Rocks are nature’s time machine. The ancient surface of Mars can provide a window into the early history of the solar system, whereas plate tectonics have largely erased that history on Earth. So if we can study ancient rocks on Mars, we can better understand how planets like ours evolved,” says Tahu. “And by studying extreme environments on Earth and the potential for life on Mars, that knowledge can intersect and intertwine and really inform our understanding of habitability in the solar system.”