Although radio waves are still the primary means of communication in outer space, NASA’s Psyche spacecraft has made significant progress by employing lasers to transfer data over enormous interplanetary distances at previously unheard-of rates.
Radio has proven to be a useful tool for connecting Earth to orbiters, rovers, and even the Voyager probes that are exploring space. However, when transferring big databases, its shortcomings become clear. For example, it took 15 months for New Horizons to return with the 50 GB of data from its flyby with Pluto.
Enter lasers, offering a potential solution. Data encoded in light waves packs more densely than radio waves, enabling faster transmission. While successful tests between satellites and Earth have been conducted, scaling this technology for deeper space has been a challenge.
The recent success of Psyche by NASA modifies the rules. The spacecraft, which is presently traveling to the asteroid belt, returned data back from an astounding 140 million miles (225 million km) away, which is 14 times farther than the Sun and farther than previous laser experiments. The test, which was aiming for 1 Mbps, obtained an astounding 25 Mbps, which is equivalent to the internet bandwidth required for 4K video streaming.
This milestone paves the way for faster communication in the future, crucial for sending high-resolution images and data when humans finally set foot on Mars. The Deep Space Optical Communications (DSOC) instrument onboard Psyche successfully transmitted data to both Palomar Observatory and NASA’s Deep Space Network, demonstrating compatibility with existing radio systems.
Additional attempts have included using numerous receivers to reduce weather disruptions and delivering data to and from Psyche over a round trip distance of 280 million kilometers.
With its enormous potential, laser technology could completely transform deep-space communication and enable faster, more effective data transfer throughout our solar system and beyond.
