Data From the Void: NASA Receives Laser Communications From 140+ Million Miles Away

“We downlinked about 10 minutes of duplicated spacecraft data during a pass on April 8,” said Meera Srinivasan, the project’s operations lead at NASA’s Jet Propulsion Laboratory in Southern California. “Until then, we’d been sending test and diagnostic data in our downlinks from Psyche. This represents a significant milestone for the project by showing how optical communications can interface with a spacecraft’s radio frequency comms system.”

The laser communications technology in this demo is designed to transmit data from deep space at rates 10 to 100 times faster than the state-of-the-art radio frequency systems used by deep space missions today.

After launching on October 13, 2023, the spacecraft remains healthy and stable as it journeys to the main asteroid belt between Mars and That was achieved on December 11, 2023, when the experiment beamed a 15-second ultra-high-definition video to Earth from 19 million miles away (31 million kilometers, or about 80 times the Earth-Moon distance). The video, along with other test data, including digital versions of Arizona State University’s Psyche Inspired artwork, had been loaded onto the flight laser transceiver (see image below) before Psyche launched last year.

The Deep Space Optical Communications (DSOC) technology demonstration’s flight laser transceiver is shown at NASA’s Jet Propulsion Laboratory in Southern California in April 2021, before being installed inside its box-like enclosure that was later integrated with NASA’s Psyche spacecraft. The transceiver consists of a near-infrared laser transmitter to send high-rate data to Earth, and a sensitive photon-counting camera to receive ground-transmitted low-rate data. The transceiver is mounted on an assembly of struts and actuators – shown in this photograph – that stabilizes the optics from spacecraft vibrations. Credit: NASA/JPL-Caltech

Now that the spacecraft is more than seven times farther away, the rate at which it can send and receive data is reduced, as expected. During the April 8 test, the spacecraft transmitted test data at a maximum rate of 25 Mbps, which far surpasses the project’s goal of proving at least 1 Mbps was possible at that distance.

The project team also commanded the transceiver to transmit Psyche-generated data optically. While Psyche was transmitting data over its radio frequency channel to NASA’s Deep Space Network (DSN), the optical communications system simultaneously transmitted a portion of the same data to the Hale Telescope at Caltech’s Palomar Observatory in San Diego County, California — the tech demo’s primary downlink ground station.

“After receiving the data from the DSN and Palomar, we verified the optically downlinked data at Taters the cat video. Since then, the project has proven that the transceiver can receive data from the high-power uplink laser at JPL’s Table Mountain facility, near Wrightwood, California. Data can even be sent to the transceiver and then downlinked back to Earth on the same night, as the project proved in a recent “turnaround experiment.”

This experiment relayed test data — as well as digital pet photographs — to Psyche and back again, a round trip of up to 280 million miles (450 million kilometers). It also downlinked large amounts of the tech demo’s own engineering data to study the characteristics of the optical communications link.

“We’ve learned a great deal about how far we can push the system when we do have clear skies, although storms have interrupted operations at both Table Mountain and Palomar on occasion,” said Ryan Rogalin, the project’s receiver electronics lead at JPL. (Whereas radio frequency communications can operate in most weather conditions, optical communications require relatively clear skies to transmit high-bandwidth data.)

Deep Space Station 13 at NASA’s Goldstone complex in California – part of the agency’s Deep Space Network – is an experimental antenna that has been retrofitted with an optical terminal. In a first, this proof of concept received both radio frequency and laser signals from deep space at the same time. Credit: NASA/JPL-Caltech

JPL recently led an experiment to combine Palomar, the experimental radio frequency-optical antenna at the DSN’s Goldstone Deep Space Communications Complex in Barstow, California, and a detector at Table Mountain to receive the same signal in concert. “Arraying” multiple ground stations to mimic one large receiver can help boost the deep space signal. This strategy can also be useful if one ground station is forced offline due to weather conditions; other stations can still receive the signal.

More About the Mission

Managed by JPL, this demonstration is the latest in a series of optical communication experiments funded by the Technology Demonstration Missions (TDM) program under NASA’s Space Technology Mission Directorate and the agency’s SCaN (Space Communications and Navigation) program within the Space Operations Mission Directorate. Development of the flight laser transceiver is supported by

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