NASA’s Psyche spaceship has fired a laser beam at Earth from 16 million kilometres away.
Contained within that laser is data and it marks the first ‘test fire’ of NASA’s Deep Space Optical Communications (DSOC) instrumentation, which was installed on the Psyche spacecraft for the six-year mission to its namesake US$1 quintillion asteroid.
As part of the experiment, DSOC sent a near-infrared light beam containing test data to Caltech’s Palomar Observatory in San Diego, California.
The process, dubbed ‘first light’, is one of several milestones NASA hopes to meet during the course of the Psyche mission. Two weeks ago, DSOC also transmitted data from near the Moon.
DSOC will continue transmitting laser-borne data to NASA over the next two years as part of the special technology demonstration. Success will likely see technology incorporated into future spacefaring missions for deep-space communication. The use of near-infrared lasers allows more data to be packed into light beams, enabling 10-100 times as much data to be transmitted than conventional radio waves.
An upcoming test will see the instrument stream video of Mars back to Earth as the Psyche spaceship drifts past the red planet.
“Achieving first light is one of many critical DSOC milestones in the coming months, paving the way toward higher-data-rate communications capable of sending scientific information, high-definition imagery, and streaming video in support of humanity’s next giant leap: sending humans to Mars,” said Trudy Kortes, director of technology demonstrations for NASA’s Space Technology Mission Directorate.
As part of the DSOC experiment, test data was sent using uplink lasers from NASA’s Jet Propulsion Lab facility in Wrightwood, California, and downlink lasers mounted to the instrument itself. The Wrightwood uplink laser provides a ‘beacon’ for the DSOC to find and target its downlink back to Earth.
Following the successful first test, the DSOC mission control will begin refining the downlink targeting systems for future experiments. Given changes in position as the spacecraft draws further away from the Earth, precision tracking is required, with data taking about 20 minutes to reach the Earth from its current position.
“Tuesday morning’s test was the first to fully incorporate the ground assets and flight transceiver, requiring the DSOC and Psyche operations teams to work in tandem,” said Meera Srinivasan, operations lead for DSOC at JPL. “It was a formidable challenge, and we have a lot more work to do, but for a short time, we were able to transmit, receive, and decode some data.”
While mounted on a Psyche spacecraft, DSOC is a separate mission to NASA’s asteroid explorer. Psyche is still ‘booting up’ as it travels towards its target, an asteroid believed to be the metallic remnants of a dead planet core.