The satellite passes The satellites orbit Earth at speeds of up to 17,000 miles per hour, deal with extreme vacuums and rapid temperature changes, and must precisely point their antennas back at Earth. After launch, they are shaken like paint cans and subjected to deafening noises.
To prepare for this challenge, every satellite is meticulously tested before it is shipped, to ensure any loose bolts are tightened and all electrical components are working perfectly. Previously, you would have had to travel to multiple locations for various tests, but in the UK, the newly opened National Satellite Test Facility in Oxfordshire now offers a complete health check of a satellite in one place.
“Industry has been saying they need a one-stop shop where they can test large, complex satellites all in one place,” says Sarah Beardsley, director of the Rutherford Appleton Laboratory, which runs the new government-funded facility on the Harwell Science and Innovation Campus. “This is the culmination of many years of effort.”
Construction began in late 2018 after the UK government announced it would invest £99 million ($126 million) in the NSTF to develop a “world-class facility” for satellite testing. It was originally scheduled to become operational in 2020, but delays due to COVID-19 and other factors have led to the grand opening being postponed to May 2024. Multiple satellites will be tested each year, and Airbus is due to be the first customer to test its new Skynet 6A communications satellite at the facility in July.
NSTF has four test areas. Entering, wearing protective gear to keep the facility as clean as possible, the first thing you see is a huge vacuum test chamber around which the entire building was built. “There’s no door big enough to walk through,” Beardsley says. Inside, pumps can reduce pressure to 0.00001 millibars to replicate the vacuum of space, and a nitrogen cooling system can raise and lower temperatures from minus 180 to 130 degrees Celsius, the extreme temperature range that satellites experience when exposed to or blocked by sunlight in orbit.
At seven metres wide and 12 metres deep, the vacuum chamber is the UK’s largest. It’s so big that the giant doors needed to close it were built in Turkey and Italy before arriving in the UK by ship just days before the 2020 lockdown, reaching the size limit of British motorways. Portsmouth port gates had to be widened to allow the doors to be removed from the ship. “It was the biggest peacetime convoy to ever arrive here travelling north on the A34,” Beardsley says. The satellite will spend weeks, or even months, inside the chamber to ensure it can withstand the conditions of outer space. During WIRED’s visit, a mock satellite called the Iron Chicken was on display, a deep dive into the characters from the cult-loved British children’s cartoon who live in a metal nest orbiting the moon. Clangers— proudly displayed in the entrance to the room.
After the vacuum chamber tests, the satellite is sent to a vibration and acoustic test chamber, where it is violently rocked horizontally and vertically on two pads powered by two electromagnetic engines (nicknamed Wallace and Gromit, after the stop-motion animation characters) that simulate the extreme conditions of launch. The rocking subjects the satellite to a force of 222 kilonewtons, four times the bite force of a T-Rex. If the satellite is even the slightest bit loose, these machines will find it.
During the acoustic tests, a giant wall of 48 speakers will blast the satellite with white noise at up to 146 decibels. For humans, it’s like standing inside an airplane jet engine. “You would suffer severe hearing loss,” says Ian Horsfall, dynamics group leader at RAL Space. The tests are designed to replicate both the rumble of a rocket engine during launch and the excruciating volume of the top of the rocket, where the satellite will be stored en route to orbit.
In the antenna test chamber, 40,000 foam spikes attached to the walls absorb all the noise and electromagnetic waves from the satellites, and the room acts as a Faraday cage to block any electromagnetic waves that come in. They then focus the satellite’s antenna onto a receiver inside the room to see if it can point that beam from its orbit to Earth, despite being hundreds or thousands of kilometers away and moving at a very high speed.
