Sending anything into space is inevitably risky, which is even more true when the spacecraft has been designed to last decades, as was the James Webb Space Telescope. Remarkably, the telescope launched in December 2021, successfully unfolded its hardware as it traveled to its orbit around the sun, and recently NASA shared how they tested Webb to ensure this triumph.

Spacecraft typically go through a process called vacuum testing in which they are placed inside an existing vacuum chamber that sucks out all the air and simulates the cold temperatures of the space environment. This wasn't possible with Webb because the side of the telescope that always faces the sun and Earth is protected by an enormous sunshield.

Testing wasn’t without troubles, however. In 2016, part of Webb was being put through vibration testing to ensure it could withstand the jostling of a launch, when the team heard a loud crack. “That was probably the scariest point," said Geithner. Fortunately, the hardware was not permanently damaged and engineers added dampers to help prevent launch fractures.

The testing team calculated there were 295 single-point failures that could have damaged the mission. "All of those failures could have happened, and they didn't, thanks to all the [...] testing implemented over the years," Geithner said. Those years-long testing processes proved worth it, as Webb will be able to keep collecting science data for at least 20 more years.