!!Con
4 HN recommenders · recommended in 4 months, 2024–2026
35:25 · 8K views · Sep 9, 2024
Bruce Waggoner of the Voyager team describes how engineers diagnosed Voyager 1's 2023 loss of telemetry and patched its flight software from 15 billion miles away. The talk covers the spacecraft's architecture and the scarcity of old documentation.
Recommended as an amazing blind-debugging story with deep detail on 1970s spacecraft computing.
6 comments from Hacker News
When Voyager failed last year with a CMOS memory error, one of the big problems was that a bunch of low level information was gone or conflicting. For example, they sometimes had to guess assembler instructions because the code printouts were low quality photocopied pages. Or because there were handwritten comments or comments scratched out with pencil without any clue about why it was done. One saving grace was the fact that the architecture and the code space was simple enough so that they could reason through the symptoms and actions to take, something that would have been much harder with modern spacecraft. Check out this amazing talk: this video
2 weeks ago, Bruce Wagoner from the Voyager program gave a talk at !!Con about how they recovered from the CMOS memory issue that they had a year ago. It’s basically blind debugging with a latency of 45 hours. The talk is amazing and goes through the computer architecture of the spacecraft as well as the challenges of dealing with something that is so old, with so documentation that has conflicting information or unreadable etc. this video
Check out this talk: this video The source code isn't hiding in a repo somewhere for security reasons — it's spread around on various pieces of paper and computers over the last 50 years. There isn't a single source of truth. Adds a whole other level of wizardry to keeping the thing running.
I had the extreme pleasure of seeing Bruce Waggoner of the Voyager team give a keynote at !!Con just last month. The recording landed on YouTube just a couple days ago, so this is great timing: this video
You might like this and or find it inspiring, in case you haven't seen it already: Saving Voyager 1! - Bruce Waggoner at !!Con 2024 - this video Edit: Also, please do share when it's playable :)