Buzz Aldrin and Neil Armstrong took the first steps on the lunar surface in what is perhaps the most memorable spacewalk in history.
This time, the astronauts were prepared for the zero-gravity setting of space.
They trained in underwater environments on Earth to simulate the sensations they’d feel on the lunar surface.
Many Apollo-era astronauts were able to spend more than seven hours spacewalking on the Moon’s surface, thanks to physical training and upgrades to their spacesuits.
When the first U.S. space station lost its micrometeoroid shield after launch, a crew of savvy astronauts flew up to repair it.
The successful repair marked the first time this kind of maintenance work was done in space — a practice that is now common onboard the ISS.
In the 1980s, a Soviet team created a tool to enable spacewalking astronauts weld in space.
This ambitious international project was assembled in low-Earth orbit over the course of 10 years.
Astronauts have spacewalked to assemble, build and maintain parts aboard the station many times since.
Future advances in technology and our understanding of space could enable us to complete even more complex tasks off-Earth — and even on other worlds.
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