The World Wide Web will eventually need to be expanded throughout the cosmos, and NASA has showcased a crucial technological advancement that could make this possible by beaming laser communications over a distance of over 16 million kilometers (10 million miles).
The achievement, made in November 2023, marked the first time that optical communications have been delivered beyond a distance that is roughly 40 times farther than the Moon is from Earth.
While radio waves have historically been used to communicate with far-off spacecraft, higher light frequencies, such as near infrared, provide a significant increase in bandwidth and consequently faster data transfer rates.
‘First light’ refers to the successful establishing of the communication link during the test, which was a component of NASA’s Deep Space Optical Communications (DSOC) experiment.
“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,” stated at the time NASA Headquarters’ director of technology demonstrations, Trudy Kortes.
Similar technology that is integrated into optical fibers is used by all of us for high-speed, ground-based communications; but, in this case, it was modified for usage via outer space to enhance currently used techniques for returning data to Earth.
Engineers can readily transfer infrared light in the form of laser beams. The light will not move much faster as a result of this, but it will be more organized and limited to a small channel. This is more difficult to intercept and uses a lot less power than a dispersion of radio waves.
That does not imply that the task is easy. A superconducting high-efficiency detector array is one of the heavy-duty instruments needed to prepare the data for transmission and translate it at the other end because the data bits are embedded in the photons that the laser emits.
Having the system adjust its placement configuration in real time presents another difficulty. In the most recent test, it took the laser photons fifty seconds to go from the spacecraft to the telescope, and throughout that time, both were traveling at high speed through space.
The Psyche spacecraft is currently on a multi-year journey to explore the asteroid belt between Mars and Jupiter. The laser transceiver responsible for the successful connection is located on board. It established communication with the Californian Palomar Observatory’s Hale Telescope.
Tests will continue to be conducted to ensure that this cutting-edge near-infrared laser communication technology is as trustworthy and quick as it needs to be in preparation for Psyche’s planned flyby of Mars.
“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,” according to Meera Srinivasan, the NASA Jet Propulsion Laboratory’s DSOC operations head.