In 1962, when astronaut John Glenn was preparing for an orbital mission, mathematician Katherine Johnson was called by the US space agency Nasa for an important task: calculating trajectories.
According to Nasa’s website, the complexity of the orbital flight, which would make Glenn the first American to orbit Earth, required the construction of a communications network that would link tracking stations around the world to computers in Washington, Florida and Bermuda. These computers were programmed with orbital equations that would control the trajectory of Glenn’s Friendship 7 spacecraft. But these machines were also prone to glitches. So, Glenn asked engineers to enlist Johnson to run the same numbers through the same equations programmed into the computer, but by hand, on a desktop mechanical calculating machine. “If she says they are good,’” Johnson remembers the astronaut saying, “then I am ready to go.” Glenn’s flight was a success—and changed the course of human spaceflight.
Johnson’s contribution showed the importance of calculations and computing in space exploration. On 20 February, a modern-day computing system was launched to the International Space Station (ISS) on board a cargo resupply spacecraft—SS Katherine Johnson—named after her. The Spaceborne Computer-2, or SBC-2, designed by Hewlett Packard Enterprise (HPE) to help astronauts process data in space, is the second iteration of a proof-of-concept that was sent to the space station in 2017. This was a commercial, off-the-shelf computer system in space that successfully performed more than one trillion calculations (or one teraflop) per second for 207 days without requiring a reset, according to Nasa.
“In general, they don’t do any computation on board the space station. It’s designed to safely house, support the human beings (astronauts) and then power and cool experiments with satellite downlinks of their data. They rely heavily on that downlink and process it down on Earth,” says Mark Fernandez, the principal investigator for SBC-2 and solution architect, converged edge systems, at HPE.
“But as we get further out there (in space exploration), to the Moon and to Mars, and to a certain extent on the ISS, we have got a bottleneck in the bandwidth coming down. We could solve the bottleneck but the world is moving to edge computing. We can get insights faster,” Fernandez explains in a video call from Greer, South Carolina. “I am talking about (going) from months to minutes.”
Fernandez explains “edge computing” in simple terms. It involves processing the data where it is generated “to extract the insight that you need”—which is much less than the raw data— and just transmitting that. Take 3D printing, for instance. Astronauts on the ISS have been using 3D printing to solve the different challenges of long-duration spaceflight since 2014. They have 3D-printed spare parts and tools in zero gravity, including a wrench. Many of these items are then sent to Earth for testing.
Sometimes, researchers run simulations to see if it’s safe to use a 3D-printed object. With SBC-2, which will offer much higher computing power than its predecessor, such simulations could be conducted on the station itself, saving the crew valuable mission time.
Astronauts can change the way they conduct research based on readily available data and improve decision making, says Fernandez. “I often say that the purpose of space exploration is insight, not data collection,” he adds. “Scientists don’t need to see 200 gigabytes of genome data. They need to see the portion of the genome that is different than it’s supposed to be.... They don’t need all of that 4K ultra HD video footage of the earth. They need to see when that lightning strike hit or when that polar ice broke away. They need to see these events. We can help downsize that.”
Designing a computer system that survives the launch sequence, high levels of radiation and microgravity was tricky. SBC-2 consists of certain technologies—like an edge system—targeted for harsh environments on Earth, like oil and gas refineries and manufacturing plants. The computing system is designed to withstand higher temperature, shock and vibration levels. “Spaceborne Computer-2 successfully completed 186 Nasa tests and requirements,” Fernandez explains.
These included a “shake table” test programmed in accordance with the G-forces of the launch. The system was flown to the space station in two specially made lockers. “If you are going to mount something into the ISS, it has specifications,” says Fernandez. “We constructed these lockers out of aircraft-grade aluminium. They were powder-coated with an approved colour, which has low reflectance, to avoid glare in the astronauts’ eyes,” he adds. “It’s not a colour that will catch your attention. They don’t want to catch the astronauts’ attention unless it’s something of importance, like a red blinking light.” Back on Earth, Fernandez and HPE researchers will receive status updates on the system’s health and functioning every six seconds.
SBC-2, with an expected mission duration of two-three years, will help in a range of research activities: from real-time monitoring of astronauts’ physiological conditions, to using sensor data for measuring air pollution, and tracking objects in space. For now, the “edge”—or the source of all this data—will be the space station. In the near future, Fernandez hopes this “edge” can be a deep space exploration spacecraft or Mars habitat.
“Space travel and survival are things that you can do. But you are going to need modern computers to go out there.... We use them in everything that we do here.... We can provide scientists power, cooling, installation and networking. But part of our infrastructure should include computational capability.”