DSOC Gives the First Light to a New Era of Space Communication

On November 14, 2023, NASA’s Deep Space Optical Communications (DSOC) experiment received and successfully sent the first laser beam from behind the Moon orbit. After a week, the device mounted on the Psyche spacecraft reached a transmission rate of 63 Mbps at 19 million kilometers of distance, demonstrating a much higher performance than standard radio transmissions.

It's been a good week for DSOC.

After achieving "first light," the tech demo has also now…
✨Sent data from nearly 12 million miles / 19 million km away.
📈Demonstrated a data rate of nearly 63 megabits per second – as quick as broadband internet. (That's fast for space!) https://t.co/fTeUHFPAlx
— NASA JPL (@NASAJPL) November 22, 2023

A giant leap in space communication

Optical communication was a revolution in wired communication, enabling improved data transfer by orders of magnitude. NASA is demonstrating that it could be applied even for space communication, increasing data rates with 10 to 100 times the capacity of current radio systems used by spacecraft.

The Lunar Laser Communications Demonstration was the first record-breaking experiment run by NASA in space, with a downlink of 622 Mbps of data from the Moon. Last year, the TeraByte InfraRed Delivery system downlinked over 200 Gbps from Low Earth Orbit, during a six-minute pass high above its corresponding ground station.

Illustration of TBIRD downlinking data over lasers links to Optical Ground Station 1 in California. Credits: NASA / Dave Ryan. — *Illustration of TBIRD downlinking data over lasers links to Optical Ground Station 1 in California. Credits: NASA / Dave Ryan*

To test this technology for deep space missions, NASA integrated the DSOC experiment on the Psyche spacecraft, launched this year and en route to reach its final destination, asteroid 16-Psyche.

*Deep Space Optical Communications (DSOC) integrated into the Psyche spacecraft. Credits: NASA/JPL-Caltech*

DSOC, high-speed deep space communication

The DSOC system consists of a flight laser transceiver, a ground laser transmitter, and a ground laser receiver. The high-power laser signal of the ground transmitter also acts as a beacon for the spacecraft, allowing it to align the transceiver to the ground station and begin the communication session. The first “light” exchanged by the DSOC system on November 14, was a crucial achievement for the pointing system since the positions of Earth and the spacecraft change as the photons travel.

This first phase of the demonstration will continue for more than six months until Psyche will be around 1 AU (150 million kilometers) from Earth.

Psyche's Mission Timeline. Credits: NASA/JPL-Caltech. — *Psyche’s Mission Timeline. Credits: NASA/JPL-Caltech*

DSOC will resume operations for a second and final test when the Psyche spacecraft will approach Mars in 2025 to receive a gravity assist. This experiment will provide valuable data for future missions to the Red Planet, proving (or not) that optical communication could work from a distance of up to 390 million kilometers.