the-ancient-tech-keeping-space-missions-alive

[ssfc72]

A nice BBC article about very old space mission hardware, running on very old computer software OS's.

https://www.bbc.com/future/article/20230815-the-ancient-tech-keeping-space-missions-alive

One example is using a modern Linux Distro to emulate an old OS. 

[Jason]

Thanks for sharing. It's amazing to me that the missions are still going after almost 5 decades. That's almost as old as me. I remember as a kid looking through astronomy magazines showing the latest pictures of the Voyager probes. They were so amazing.

I tried to find more details about the OS on it but wasn't able to, but obviously, it predates Linux but not Unix. It could be custom written with the tight memory requirements. This article from Wired has even more details. The specs are quite interesting in showing how far computers and electronics have come.

The computers aboard the Voyager probes each have 69.63 kilobytes of memory, total. That's about enough to store one average internet jpeg file. The probes' scientific data is encoded on old-fashioned digital 8-track tape machines rather than whatever solid state drive your high-end laptop is currently using. Once it's been transmitted to Earth, the spacecraft have to write over old data in order to have enough room for new observations.

The Voyager machines are capable of executing about 81,000 instructions per second. The smart phone that is likely sitting in your pocket is probably about 7,500 times faster than that. They transmit their data back to Earth at 160 bits per second. A slow dial-up connection can deliver at least 20,000 bits per second.

The Voyager probes are always sending out a signal. Voyager 1 has a 22.4-Watt transmitter – something equivalent to a refrigerator light bulb – but by the time its beacon reaches us, the power has been reduced to roughly 0.1 billion-billionth of a Watt. NASA has to use its largest antenna, a 70-meter dish, or combine two 34-meter antennas, just to hear Voyager.

https://www.wired.com/2013/09/vintage-voyager-probes/

For more fascinating trivia, look up info about the gold disc on the outside of the probes that have visuals of humans, showing where the probes came from (like a map to our solar system) and music and sounds from Earth. It's impressive in its own way.