The engineer keeping astronauts safe 25 years and counting

Mark Elder has spent more than two decades making sure the people floating outside the International Space Station don't die. It's a job that requires obsessing over every bolt, bearing, and battery in a spacesuit—because in the vacuum of space, there's no margin for error.

As the EVA hardware manager for NASA, Elder leads the team responsible for the spacesuits and tools that protect astronauts during spacewalks. Every time an astronaut steps outside the station, his work is there with them. His team coordinates with Mission Control in Houston to ensure the suits operate reliably in an environment that's actively trying to kill you—extreme cold, radiation, micrometeorite impacts, near-total vacuum.

But Elder didn't start out designing life-support systems. At age 16, he attended Space Academy in Huntsville, Alabama, after his parents gave him a book called "The Astronauts" when he was young. He became obsessed. After graduation, he worked for Pratt & Whitney on jet engines, but his heart wasn't in it. When he learned that Hamilton Sundstrand—a fellow company in the same corporate umbrella—was the prime contractor for NASA spacesuits, he transferred immediately. "My career at NASA finally began," he said.

From jet engines to lithium batteries in space

Over the years, Elder took on increasingly complex work. His breakthrough came when he led the team that developed the EVA Long Life Battery—the first human-rated lithium battery ever used in space. This sounds straightforward until you remember that lithium batteries were under intense scrutiny for safety concerns at the time. His team created a rigorous test plan to certify the battery for human spaceflight, and eventually signed off on it.

"Finally signing the certification paperwork was satisfying," Elder said, "but watching an EVA powered by the batteries provided a great sense of pride." That innovation opened the door to safer, higher-capacity batteries that power spacewalking today and will eventually support lunar missions.

Along the way, Elder learned something unexpected about leadership. "When I first became a team lead, I thought success meant making quick decisions and moving fast," he said. "I learned that leadership is really about listening. Strong teams are built on trust and open communication." He also learned to assume positive intent—that in a place like NASA, where everyone is deeply passionate, disagreements aren't opposition. They're just different approaches to the same goal.

The Moon is next

Now, as NASA prepares for Artemis missions to the lunar surface and eventual Mars exploration, Elder's 25 years of maintaining and refining spacesuits on the station inform the design of next-generation exploration suits. "The foundation we've built on the space station is critical for the future," he said. "Every tool we've refined, every system we've upgraded—it all feeds into how we'll operate on the lunar surface and eventually on Mars."

When he's not thinking about spacesuits, Elder builds things in his workshop. Woodworking, he says, calms him down and gives him a sense of accomplishment—the same feeling he gets watching an astronaut float safely in the void, protected by work his team refined over decades.

"There will be challenges," Elder said. "As long as we keep dreaming, we will see the next generation walking on the Moon and heading to Mars." That dream, the one that started with a book, is now the foundation for humanity's next leap.