(Credit: NASA/JPL)
NASA has shown you can indeed use lasers to beam data from beyond the Moon to Earth, making it a potential way to upgrade space-based communications.
NASA conducted the successful test on Nov. 14 using the agency’s Psyche spacecraft, which launched last month to investigate an asteroid. The Psyche craft also contains an experimental optical communication system, called DSOC, that can beam data back to Earth using near-infrared lasers.
The test took place when Psyche was nearly 10 million miles away from our planet, or about 40 times the distance from the Moon. “This is the farthest-ever demonstration of optical communications,” NASA said in the announcement.
The DSOC system works by using an observatory in California to emit a laser beacon into the sky. The Psyche craft then locks on to it and can orient its transceiver and point the craft’s downlink laser back to a separate observatory capable of decoding the signals.
Specifically, the craft can send particles of light, also known as photons, to the observatory on Earth. “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 a NASA Jet Propulsion Lab team lead Meera Srinivasan.
“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,” Srinivasan added.
There’s no word on the data speeds since NASA is still working to optimize the laser connection between Psyche and the agency’s stations on Earth. But the goal is to deliver data 10 to 100 times greater than the existing radio frequencies space probes use for communication.
“Both radio and near-infrared laser communications utilize electromagnetic waves to transmit data, but near-infrared light packs the data into significantly tighter waves, enabling ground stations to receive more data,” NASA explains. The result means future spacecraft, including those from SpaceX, could send higher-quality images and perhaps even conduct video streaming through such laser beams.
Psyche will continue beaming the lasers during a “two-year technology demonstration. A key challenge will be trying to receive the laser signals from the spacecraft over the growing distance between the spacecraft and Earth. “Reaching their targets will be akin to hitting a dime from a mile away while the dime is moving,” NASA says. In 2029, the spacecraft is then expected to reach the asteroid 16 Psyche, which it will proceed to orbit.