NASA's deep-space laser comms demo has left the chat

NASA's Deep Space Optical Communications (DSOC) demonstration has completed its final pass, although there is a chance the system might be reactivated in the second half of 2026. Carried aboard NASA's Psyche mission, DSOC demonstrated how data encoded in lasers could be reliably transmitted, received, and decoded. On …

[tip pc]

Downlink?

The technology worked as advertised or better. At 19 million miles (30 million km) from Earth, DSOC achieved 267 Mbps. At 386 million kilometers (240 million miles), it achieved a sustained downlink data rate of 6.25 Mbps, peaking at 8.3 Mbps.

Is the downlink on earth or the probe?

i appreciate the article mentioned an earth downlink being a telescope but sometimes 'downlink' is used interchangeably. i will assume the earth receiving end for all mentions in the article.

would be good to know the receive & transmit rates of the probe & separately the earth receiving station.

I'd expect the probe to be able to send at a higher rate than the probe due to more power available here.

for the earth station to receive at 6.25mbps from the probe at 240 million miles away is extremely impressive.

& yes i appreciate that the probes send rate is likely more important than the receive rate as its the data it has recorded that we want.

I also wonder how the rate is windowed down given the latency peaks at 22 mins to mars type distances. i guess spending at least 66 mins to max bandwidth & link quality is worth the higher bandwidth

[Annihilator]

Re: Downlink?

It's technically two-way laser communications, but the uplink to the probe is at what Nasa calls a "low rate" one, also used as a beacon for Psyche to aim at. The transmitter is actually about 100 miles away from the receiving telescope, but yeah, there's still a need for a hefty one (5m) to receive the signal at the higher rates.

It's a demonstrator though, it's main goal is for proving data links between human missions to Mars, rather than probes.

https://www.jpl.nasa.gov/missions/deep-space-optical-communications-dsoc/

[ComputerSays_noAbsolutelyNo]

Twinkle twinke little star

What are you saying?

-> where's my high-speed laser ultra morse code book

[Christoph]

The primary downlink station is a 200-inch (5.1-meter) telescope at Caltech's Palomar Observatory in San Diego County.

I can remember when the Palomar 200 inch was the biggest telescope in existence. Now it's useful as a comms receiver, and El Reg has to explain what it is for readers who haven't heard of it.

[Annihilator]

Ah don't feel bad, El Reg would explain what MS Clippy was too.