Debugging at a Distance
Curated by Claude · 12 videos · 8 hr 7 min
Hacker News loves a war story about software you can't touch, and spacecraft are the most extreme case. This playlist runs roughly in order of history: two ways into the Apollo Guidance Computer, the restoration of a real one, then Voyager's 1970s computers, a Lisp REPL on Deep Space 1, a visit to the antenna that still talks to Voyager, and the 2023 rescue of Voyager 1. It ends with the photo Voyager took on its way out.
Play all on YouTube- 11:21:22
Light Years Ahead | The 1969 Apollo Guidance Computer
2.8M views • 6 years agoTNMoCRobert Wills of TNMoC explains the Apollo Guidance Computer hardware and software, then walks through the Apollo 11 landing procedure step by step, including the 1202 alarms.The way in: Robert Wills explains the AGC and then walks through the Apollo 11 landing step by step, 1202 alarms included, and HN keeps calling it mandatory viewing.
- 21:01:42
34C3 - The Ultimate Apollo Guidance Computer Talk
324K views • 8 years agomedia.ccc.deMichael Steil and Christian Hessmann's 34C3 talk explaining the Apollo Guidance Computer end to end: hardware design, operating system, and mission software.Once the landing story makes sense, Steil and Hessmann go through the whole machine layer by layer, from hardware to OS to mission software, which commenters call the most complete AGC talk there is.
- 321:04
Apollo Guidance Computer Part 1: Restoring the computer that put man on the Moon
588K views • 7 years agoCuriousMarcThe first episode of CuriousMarc's series restoring a real Apollo Guidance Computer, led by AGC expert Mike Stewart. They set up a makeshift lab in a Houston hotel room to open up a rare machine owned by a private collector.Now you see the real thing: CuriousMarc and Mike Stewart open a privately owned AGC in a Houston hotel-room lab, the first episode of a series HN recommends whole.
- 449:03
Apollo Core Rope Memory (Apollo Guidance Computer Part 30)
759K views • 3 years agoCuriousMarcCuriousMarc's Apollo Guidance Computer restoration series looks at core rope memory, the ROM that held the Moon landing programs. Mike Stewart builds a custom reader to recover lost AGC programs.Thirty episodes later, the team builds a reader to recover lost programs from core rope memory, which a commenter calls the deepest dive on rope ROM anywhere.
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27:58Build an electroluminescent glass panel display -- an Apollo DSKY
522K views • 7 years agoApplied ScienceApplied Science builds a replica Apollo DSKY using an electroluminescent driver circuit and screen-printed conductive ink, with source and PCB files published.A maker interlude before Voyager: Applied Science rebuilds the astronauts' electroluminescent display panel from scratch, so you see the other end of the AGC too.
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40:05"Uptime 15,364 days - The Computers of Voyager" by Aaron Cummings
349K views • 7 years agoStrange Loop ConferenceA Strange Loop 2019 talk by Aaron Cummings on the computing systems aboard Voyager 1 and 2, which control the spacecraft and record and return data decades after launch in 1977.Moves from 1969 to 1977: a Strange Loop tour of the three computer systems that still fly Voyager, and why they have lasted so long.
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1:10:43The Remote Agent Experiment: Debugging Code from 60 Million Miles Away
23K views • 14 years agoGoogle TechTalksRon Garret tells the story of the Remote Agent Experiment on NASA's Deep Space 1, where autonomous software controlled a spacecraft in 1999. He describes debugging Lisp code remotely from millions of miles away.Ron Garret's first-hand account of finding a race condition in Lisp on Deep Space 1 through a live REPL in 1999, which HN cites in nearly every thread about remote REPLs.
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20:16How To Contact The Voyager 2 Probe (PART 1)
93K views • 9 years agoEEVdiscoverDave Jones of EEVblog and Richard Stephenson tour the 70m DSS43 dish at the Canberra Deep Space Communication Complex and explain how NASA talks to Voyager 2. It covers the transmitters, receivers and tracking involved.Before the rescue story, see the other end of the link: EEVblog's Dave Jones tours the 70m DSS-43 dish in Canberra with its operations supervisor.
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13:01Pinging The Voyager 2 Probe (PART 2)
75K views • 9 years agoEEVdiscoverPart two of EEVblog's visit to the NASA/CSIRO Canberra Deep Space Communication Complex, showing the control room and how operators contact Voyager 2. It includes live data and spectrum displays.Inside the control room, with live spectrum displays of a signal that left the spacecraft about a day earlier.
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35:25Saving Voyager 1! - Bruce Waggoner at !!Con 2024
8K views • 2 years ago!!ConBruce 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.A short, lively version of the 2023 telemetry failure from someone on the team, covering 1970s architecture and documentation that had gone missing.
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1:03:45How We Diagnosed and Fixed the 2023 Voyager 1 Anomaly from 15 Billion Miles Away
17K views • 1 year agoFlight Software WorkshopJPL's David Cummings presents at the 2025 Flight Software Workshop how the team diagnosed and fixed the 2023 Voyager 1 anomaly from billions of miles away. It walks through the flight computer and the memory fix.The full engineering version for flight-software people: no simulator, a failed memory chip, and code relocated around it, which one commenter called mind-blowing reverse engineering.
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3:31Carl Sagan - Pale Blue Dot
8.7M views • 17 years agocarlsagandotcomCarl Sagan's narration of the Pale Blue Dot passage, reflecting on the Voyager photograph of Earth as a tiny speck in space. It is a short meditation on humanity's smallness and shared home.The closer: Voyager 1 took this photo of Earth in 1990 on its way out, and HN commenters say they rewatch Sagan's three minutes about it every so often.