Satellites pass through a lot. As they hurtle around our planet at speeds of up to 17,000 miles per hour, they must contend with the extreme vacuum of space and enormous temperature swings while trying to precisely point their antennas back at Earth. And that’s after liftoff, where they’ll be jolted like a paint can and launched with a deafening noise.
To prepare them for this test, all satellites are meticulously tested before they are sent out, ensuring that every loose screw is tightened and all the electrics are in perfect working order. This used to require travelling to multiple locations to carry out different tests, but in the UK the newly opened National Satellite Test Centre in Oxfordshire offers full satellite health checks under one roof.
“The industry said they needed a one-stop shop where they could do all their testing of large, complex satellites in one place,” says Sarah Beardsley, director of the UK government-funded Rutherford Appleton Laboratory Space, which runs the recent facility at the Harwell Science and Innovation Campus. “This is the result of years of hard work.”
Construction began in delayed 2018 after the UK government announced it was investing £99m ($126m) in the NSTF to develop a “world-class facility” for testing satellites. The project was originally due to start operating in 2020 but has been hit by delays, including Covid, pushing its grand opening to May 2024. Multiple satellites will be tested each year, with Airbus set to be the first customer to employ the facility in July for its recent Skynet 6A communications satellite.
Inside the NSTF are four test areas. The first one you’ll encounter upon entering—after putting on protective gear to keep the facility as immaculate as possible—is a massive vacuum test chamber around which an entire building had to be built. “There’s no door big enough to squeeze through,” Beardsley says. Inside the chamber, pumps can reduce pressure to just 0.00001 millibars, mimicking the vacuum of space, while a nitrogen cooling system can raise and lower temperatures from minus 180 to 130 degrees Celsius, the extreme range a satellite might experience as it enters and exits the sunlight in orbit.
At seven metres wide and 12 metres deep, it is the largest vacuum test chamber in the UK. It is so enormous that the huge doors needed to seal the chamber, built in Turkey and Italy before arriving in the UK by boat just days before the 2020 lockdown, reached the size limit of what could fit on a British motorway. The dock gates in Portsmouth had to be widened to allow access to the doors on the ship. “We had the largest peacetime convoy coming down the A34 to get here,” says Beardsley. The satellites will spend weeks or even months in the test chamber to ensure they can cope with the conditions in space: When WIRED visited, a mock satellite called The Iron Chicken — a deep-dive shot of the character who lives in a metal nest orbiting the moon in the iconic British animated children’s film Liars—occupied the seat of honor at the entrance to the room.
After the vacuum chamber test, the satellites will be directed to a vibration and acoustics test room, where they will be shaken violently—horizontally and vertically—on two platforms powered by a pair of electromagnetic thrusters (named Wallace and Gromit after beloved stop-motion characters) that simulate the extreme conditions of launch. The shaking will subject the satellite to a force of 222 kilonewtons, equivalent to four times the bite of a T. Rex. If anything on the satellite is even a little loose, these machines will detect it.
During the acoustic tests, a giant wall of 48 loudspeakers will blast up to 146 decibels of white noise at the satellites. For a human, it would be like standing in a jet engine. “You would have severe hearing damage,” says Ian Horsfall, head of the dynamics group at RAL Space. The test is designed to mimic both the noise of rocket engines during liftoff and the ear-splitting volume at the top of a rocket—where satellites are stored on their way to orbit.
In the antenna test room, 40,000 foam spikes on the wall absorb all noise and electromagnetic waves from the satellites, while the room acts as a Faraday cage, blocking incoming electromagnetic radiation. A satellite antenna can then be pointed at a receiver in the room to see if its beam can be directed from orbit back to Earth, despite being hundreds or thousands of miles away and moving at tremendous speeds.