Communicating in space presents significant challenges, accentuated by large distances, such as those that separate Earth from Mars. In anticipation of missions to Mars in the coming decades, NASA, along with other space agencies, has begun testing new methods to improve transmissions. One example is the optical system aboard NASA’s Psyche probe, which is headed for asteroid 16 Psyche and expects to reach it in 2029.
This system uses the near-infrared laser to overcome the limitations of traditional radio communications, allowing a greater amount of data to be transferred to Earth. One of the first tests carried out included the transmission of a video of a cat playing with a laser pointer, demonstrating the potential of the Deep Space Optical Communications (DSOC) communication system.
New successes in long-distance data transmission
Recently, JPL and the space agency confirmed that the Psyche probe successfully used the DSOC system to send data from a distance of 226 million kilometers. This represents a notable improvement over the distances covered previously. JPL’s Meera Srinivasan highlighted the significant technological advancement, explaining that a lot of duplicate data was transmitted in about 10 minutes on April 8, marking a milestone for the project.
Despite the seven times greater distance, the transmission speed was lower than in the December 2023 test, with a peak of 25 Mbps and a minimum of 1 Mbps. During the test, NASA Psyche simultaneously transmitted both radio frequency, to Deep Space Network, both via laser at Caltech’s Palomar observatory in California.
One of the biggest obstacles for optical transmissions remains interference from terrestrial weather conditions, which can interrupt signal reception in the presence of dense clouds. However, under clear skies, the performance of the laser system is optimal. Although DSOC is not yet the main system, further tests are needed to confirm its effectiveness, including by other probes and satellites. This approach could gradually replace traditional radio wave technologies, marking an era of more efficient and capacious space communications.
