NASA’s Deep Space Atomic Clock is set to be launched aboard a Falcon Heavy later this month. The GPS-like instrument will allow spacecraft to manoeuvre autonomously without input from operators on Earth.
Currently, when a spacecraft venturing beyond Earth’s orbit requires navigational information, operators send a signal to the spacecraft which it then sends back. Utilising atomic clocks, operators are then able to calculate exactly how long it took the signal to be returned enabling the spacecraft’s position to be calculated. That information is then relayed back to the spacecraft for navigation and manoeuvring. This process can take anywhere from minutes to several hours. The result is that anywhere near real-time manoeuvring and course correction is just not possible.
“Every spacecraft exploring deep space is steered by navigators here on Earth. Deep Space Atomic Clock will change that by enabling onboard autonomous navigation, or self-driving spacecraft,” said Jill Seubert, the deputy principal investigator.
The toaster-sized mercury ion clock was created by JPL clock physicists Eric Burt, Robert Tjoelker and John Prestage. During testing, it was found that the clock was 50 times more accurate than atomic clocks being used in the GPS network. The result is a clock that loses no more than 1 second every 10 million years.
With an extremely accurate clock onboard, a spacecraft would simply need a single signal sent from Earth to calculate its position. This would allow for a much higher degree of autonomy. Other applications for the technology could be using an array of enabled spacecraft orbiting a planet to provide a GPS-like network to robots and humans on the surface.
SpaceX will launch the Deep Space Atomic Clock aboard the Falcon Heavy Space Test Program Flight 2 (STP-2) mission from the Kennedy Space Centre on June 25 at 03:30 UTC. The clock will then be put through its paces in Earth’s obit assisting spacecraft to locate themselves in space over a one-year trial period. If it performs as accurately in orbit as it has in lab settings, the clock could be incorporated into a deep space mission as early as the 2030s.
In addition to the Deep Space Atomic Clock, an additional 24 satellites will be launched aboard STP-2. Another interesting payload set to be launched aboard the mission is a solar-sail-powered spacecraft LightSail 2, which was privately funded by members of The Planetary Society.
