NASA has to rethink some tried-and-true approaches to spacecraft navigation as it eyes more distant targets. Spacecraft need extremely accurate location measurements to plan maneuvers, but the way we’ve been doing that can be painfully slow. That’s why NASA launched a new prototype atomic clock into orbit recently. This device could revolutionize space exploration, and the team just turned it on for the first time.
The so-called Deep Space Atomic Clock went into space on a Falcon Heavy rocket earlier this year along with two dozen other payloads. Like ground-based atomic clocks, this device measures the passage of time with extraordinary accuracy, and that’s a must-have for space travel.
Current spacecraft determine their position through a convoluted and time-consuming method relying on ground-based atomic clocks. These missions have to beam signals back to Earth, allowing a clock to calculate how long it took for the signal to reach us. Then, the result goes back out to the spacecraft. This test, if successful, could lead to a new generation of spacecraft that have an atomic clock on-board rather than relying on ground-based clocks.
The Deep Space Clock is about the size of a toaster, mounted to the General Atomics Electromagnetic Systems Orbital Test Bed satellite. That’s tiny for an atomic clock, most of which are the size of a refrigerator. With an atomic clock like this one on a spacecraft, the location calculation would be one-way. Signals from Earth would allow the computer to instantly calculate a position based on how long it took for those signals to reach the spacecraft.
NASA created this compact atomic clock using a mercury ion design. It uses the oscillations of mercury ions at low temperatures to measure the passage of time. Now that the clock is online, NASA will be able to track its performance to ensure it’s accurate, and it has to be almost unbelievably so. Even a few lost nanoseconds here and there could lead to disaster as a vessel aims for precise maneuvers.
If the Deep Space Atomic Clock lives up to expectations, it should only lose one second in 10 million years. NASA will measure the clock’s performance down to the nanosecond over the coming months. Success could mean similar devices will show up on future deep-space missions to Mars, Europa, and beyond.