[HN Gopher] The first interstellar software update: The hack tha...
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       The first interstellar software update: The hack that saved Voyager
       1 [video]
        
       Author : daemonologist
       Score  : 99 points
       Date   : 2025-10-12 20:31 UTC (11 days ago)
        
 (HTM) web link (www.youtube.com)
 (TXT) w3m dump (www.youtube.com)
        
       | daemonologist wrote:
       | An excellent video from Scott Manley about last year's fix of the
       | Voyager 1 computer. Not related to the recent thruster fix.
       | 
       | Original title "The First Interstellar Software Update - The
       | Insane Hack That Saved Voyager 1"; this combined with the [video]
       | tag was too long, so I removed the "number + adjective" in
       | accordance with the HN guidelines.
        
         | daemonologist wrote:
         | See related:
         | 
         | - from David Cummings at JPL:
         | https://news.ycombinator.com/item?id=43732632
         | 
         | - from Bruce Waggoner at JPL:
         | https://news.ycombinator.com/item?id=42385393
         | 
         | - Ars article from the time of the fix:
         | https://news.ycombinator.com/item?id=40155293
         | 
         | - CNN article from when communication was lost:
         | https://news.ycombinator.com/item?id=38640900
        
           | dang wrote:
           | Thanks! Macroexpanded:
           | 
           |  _We Diagnosed and Fixed the 2023 Voyager 1 Anomaly from 15B
           | Miles Away [video]_ -
           | https://news.ycombinator.com/item?id=43732632 - April 2025
           | (18 comments)
           | 
           |  _Saving Voyager 1 [video]_ -
           | https://news.ycombinator.com/item?id=42385393 - Dec 2024 (13
           | comments)
           | 
           |  _How NASA Repaired Voyager 1 from 15B Miles Away_ -
           | https://news.ycombinator.com/item?id=40155293 - April 2024
           | (56 comments)
           | 
           |  _Voyager 1 stops communicating with Earth_ -
           | https://news.ycombinator.com/item?id=38640900 - Dec 2023 (608
           | comments)
        
       | quotemstr wrote:
       | The earlier Galileo hack was also impressive. The high gain
       | antenna (necessary for its high speed data link) got stuck trying
       | to unfurl and so the whole mission had to rely on the low-gain,
       | low-speed backup antenna --- which topped out at a glorious speed
       | of ~10 bits per second.
       | 
       | "The Galileo mission operations concept is undergoing substantial
       | redesign, necessitated by the deployment failure of the High Gain
       | Antenna, while the spacecraft is on its way to Jupiter. The new
       | design applies state-of-the-art technology and processes to
       | increase the telemetry rate available through the Low Gain
       | Antenna and to increase the information density of the telemetry.
       | This paper describes the mission planning process being developed
       | as part of this redesign. Principal topics include a brief
       | description of the new mission concept and anticipated science
       | return (these have been covered more extensively in earlier
       | papers), identification of key drivers on the mission planning
       | process, a description of the process and its implementation
       | schedule, a discussion of the application of automated mission
       | planning tool to the process, and a status report on mission
       | planning work to date. Galileo enhancements include extensive
       | reprogramming of on-board computers and substantial hard ware and
       | software upgrades for the Deep Space Network (DSN). The principal
       | mode of operation will be onboard recording of science data
       | followed by extended playback periods. A variety of techniques
       | will be used to compress and edit the data both before recording
       | and during playback. A highly-compressed real-time science data
       | stream will also be important. The telemetry rate will be
       | increased using advanced coding techniques and advanced
       | receivers. Galileo mission planning for orbital operations now
       | involves partitioning of several scarce resources. Particularly
       | difficult are division of the telemetry among the many users
       | (eleven instruments, radio science, engineering monitoring, and
       | navigation) and allocation of space on the tape recorder at each
       | of the ten satellite encounters. The planning process is
       | complicated by uncertainty in forecast performance of the DSN
       | modifications and the non-deterministic nature of the new data
       | compression schemes. Key mission planning steps include
       | quantifying resource or capabilities to be allocated,
       | prioritizing science observations and estimating resource needs
       | for each, working inter-and intra-orbit trades of these resources
       | among the Project elements, and planning real-time science
       | activity. The first major mission planning activity, a high
       | level, orbit-by-orbit allocation of resources among science
       | objectives, has already been completed; and results are
       | illustrated in the paper. To make efficient use of limited
       | resources, Galileo mission planning will rely on automated
       | mission planning tools capable of dealing with interactions among
       | time-varying downlink capability, real-time science and
       | engineering data transmission, and playback of recorded data. A
       | new generic mission planning tool is being adapted for this
       | purpose."
       | 
       | https://ui.adsabs.harvard.edu/abs/1994smog.symp..279G/abstra...
        
       | antonvs wrote:
       | It was technically "interstellar", but given its actual position
       | - still inside the Oort Cloud, for example - it's a bit
       | misleading.
       | 
       | It'd still take another 70+ thousand years for it to reach
       | another star, if it was even heading in the optimal direction for
       | that. That makes it less than 0.07% of the way to the nearest
       | star. At interstellar scales, it's basically still on Earth's
       | surface.
        
         | quotemstr wrote:
         | Still impressive to do with those latencies. Plus, the Voyager
         | team got very lucky --- if a different memory bank had failed,
         | recovery might not have been possible.
        
           | antonvs wrote:
           | I agree it was impressive.
           | 
           | My objection to using the word "interstellar" here is that it
           | gives the impression that Voyager is much further away from
           | Earth and the solar system than it really is.
        
             | Insanity wrote:
             | Eh, I agree with you but humans can't really visualize /
             | comprehend these distances regardless. It's just "very far
             | away"
        
               | 8note wrote:
               | id have gone with "extrastellar"
               | 
               | its not so far to be between two stars, but its far
               | enough from our star, at least past the firewall
        
               | locusofself wrote:
               | perhaps "extrasolar" if we want to be extra pedantic
        
               | tonyhart7 wrote:
               | "at least past the firewall"
               | 
               | what do you mean by this???? also where I can study these
               | stuff
        
               | snitch182 wrote:
               | Its past the influence of our sun. At least as measured
               | by the on board tec of the time. Sort of out in the void
               | between the stars but at these distances just barely out.
        
               | vlovich123 wrote:
               | > what do you mean by this????
               | 
               | https://www.wionews.com/photos/why-firewall-protects-our-
               | sol...
               | 
               | It's where incoming charged particles and plasma from the
               | rest of the universe collide with the solar wind - on one
               | side the "wind" (charged particles emitted by the sun)
               | heading away from our sun and pushing everything away and
               | on the other incoming particles where our wind isn't
               | strong enough anymore to overpower them. The firewall is
               | the "boundary". It's not literally a wall of fire, it's
               | not literally wind, it's not literally pushing away all
               | other particles (some have energies that can overcome the
               | solar wind and some aren't charged), and it's not a
               | discrete boundary but more a region of space.
               | 
               | Space is filled with euphemistic language to try to help
               | build mental models of reality that we actually have 0
               | experience with and can't really observe but kind of act
               | like things we do know intuitively.
               | 
               | > also where I can study these stuff
               | 
               | Well I got this link by googling "solar firewall" and
               | it's literally the first link. Improving your self
               | empowerment and willpower to look up trivially accessible
               | information yourself is step #1. There's also a small up
               | and coming website called Wikipedia that I've heard
               | contains information you can go read and contains links
               | to dig deep even further. There's also plenty of YouTube
               | personalities that devote their channel to "these stuff"
               | that can give you intro-level perspectives as they target
               | a lay audience (eg Neil deGrasse Tyson).
        
         | mkl wrote:
         | I think this was extrasolar, not interstellar.
        
       | mrbluecoat wrote:
       | Reminds me of the pen that saved the Apollo 11 astronauts:
       | https://luxurylaunches.com/auctions/apollo-11-broken-switch-...
        
       | kabdib wrote:
       | Henry S F Cooper wrote a wonderful account of debugging OS race
       | condition on the Magellan (Venus) orbiter in _The Evening Star_
        
       | modo__game wrote:
       | Mahmoud
        
       | lisper wrote:
       | Two similar incidents from my career:
       | 
       | https://github.com/rongarret/gll-mag-patch/
       | 
       | https://www.youtube.com/watch?v=_gZK0tW8EhQ&t=2340s
       | 
       | (Also recounted in https://www.corecursive.com/lisp-in-space-
       | with-ron-garret/)
        
         | qingcharles wrote:
         | It's really frustrating when you need to fix old code and the
         | dev environment is gone. Some of that stuff just isn't
         | replaceable, or it's a whole bunch of extra work, as you had to
         | do to get back to square one.
         | 
         | It isn't 100% clear from the Voyager documentaries how much of
         | the dev environments were destroyed/lost between projects being
         | canceled. I tried to get the Voyager source but it isn't
         | classified as a government record that would be subject to
         | FOIA, which is frustrating. (nothing to do with security, just
         | IP)
        
           | jpitz wrote:
           | In my experience, pretty much anything relating to
           | spaceflight is gonna be lumped under ITAR and restricted from
           | general disclosure.
        
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       (page generated 2025-10-23 23:02 UTC)