MELBOURNE, Fla. — NASA on Tuesday debuted the spacesuits that astronauts will wear during its upcoming Artemis moon missions, but the trailblazing suits that came before them were far less sophisticated.

Ondrej Doule is head of the Florida Tech Human Spaceflight Laboratory, so he knows a thing or two about spacesuits. In fact, his team has its own working spacesuit, adjustable for people of different heights.

It's a far cry from the original early 1960s suits worn by Alan Shepard and John Glenn during the Mercury program.

"Those suits were really emergency devices," Doule said. "They were designed to give the astronauts some type of atmosphere. They were not designed for any kind of enhanced performance."

Spacesuits improved in the years to come, especially when Apollo astronauts walked on the moon. But those, too, limited astronauts' mobility.

Doule said it resembled a static figure trying to move from one step to another.

"The internal overpressure is so high, compared to the exterior atmosphere, that the pressurized suit is very difficult to bend," he said.

Spacewalking shuttle astronauts had more flexible suits for work outside the International Space Station or repairing satellites in orbit. But Doule is really excited about the NASA spacesuits just unveiled — one designed for launch and reentry, another for exploring the lunar surface — and the modern ones already designed by commercial space companies.

"Hopefully, we will be able to contribute a design into the spacesuit world," Doule says of Florida Tech.

Florida Tech also has a spacesuit trainer that will allow engineering students to test future spacesuit designs.