Stations on planet Earth have sent and received messages beamed via laser from NASA’s Psyche spacecraft over 350 million kilometers (218 million miles) away. This breakthrough in optical communication shows that NASA is laying the groundwork for high-speed data links for future human missions to Mars.
NASA’s Deep Space Optical Communications technology has recently demonstrated that data encoded in lasers can be sent, received, and decoded after traveling hundreds of millions of kilometers across the Solar System.
Managed by NASA’s Jet Propulsion Laboratory (JPL) in Southern California, the Psyche spacecraft was launched in 2023 with the mission of orbiting and studying the metallic asteroid 16 Psyche, a task set to begin in 2029.
The spacecraft is also equipped with a laser transceiver, designed to send and receive data encoded in light beams from two ground stations on Earth. After the beams depart from our planet, JPL’s Table Mountain Facility fires a 3-kilowatt laser beacon toward the spacecraft, helping Psyche lock onto Earth with better precision.
Even at the speed of light, the laser takes several minutes to traverse the enormous distance between Earth and Psyche, both of which are moving at immense speeds themselves. When the optical information finally arrives at the spacecraft, it will return its own “message” back to Earth.
To spot this faint signal in the distance, scientists rely on Caltech’s Palomar Observatory in San Diego County, a giant dome capable of detecting the tiniest glimmers of light across the Solar System. The incoming photons are passed into a sophisticated detector array where the data they carry is carefully decoded, transforming faint flashes into meaningful information.
Optical communications have been used to send messages from space before – in fact, this is the 65th and final test of the technology.
Farflung spacecrafts are typically communicated with via radio waves. This is how we still receive information from Voyager 1 & 2, the iconic twin probes from the 1970s that have literally left our Solar System. However, optical communications, like lasers, are potentially a much better option as they can transmit far more data at much higher speeds.
In December 2023, their scientists were able to use laser beams to stream an ultra-high-definition video to Earth from 31 million kilometers (19 million miles) away. Aptly, the video is a 15-second clip of an adorable cat chasing a laser dot.
“NASA Technology tests hardware in the harsh environment of space to understand its limits and prove its capabilities,” Clayton Turner, associate administrator, Space Technology Mission Directorate at NASA Headquarters in Washington, said in a statement. “Over two years, this technology surpassed our expectations, demonstrating data rates comparable to those of household broadband internet and sending engineering and test data to Earth from record-breaking distances.”
In the latest feat of the Psyche mission, the distance traveled by the laser – 350 million kilometers (218 million miles) – is further than the distance between Earth and Mars – 225 million kilometers (140 million miles) on average.
This means the technology, with further tweaking, could be used to communicate signals between Earth and Mars, where NASA (and other countries) hope to send human astronauts soon. It’s exactly this kind of tech that could eventually allow us to see a livestream of a human astronaut walking and playing golf on the Martian surface.
“NASA is setting America on the path to Mars, and advancing laser communications technologies brings us one step closer to streaming high-definition video and delivering valuable data from the Martian surface faster than ever before. Technology unlocks discovery, and we are committed to testing and proving the capabilities needed to enable the Golden Age of exploration,” commented Sean Duffy, acting NASA Administrator.