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Crowdfunded, Solar-powered Spacecraft Goes Silent

Last week saw the successful launch of the Planetary Society's LightSail spacecraft, the solar-powered satellite that runs Linux and was crowdfunded on Kickstarter. The spacecraft worked flawlessly for two days, but then fell silent, and the engineering team has been working hard on a fix ever since. They've pinpointed the problem: a software glitch. "Every 15 seconds, LightSail transmits a telemetry beacon packet. The software controlling the main system board writes corresponding information to a file called beacon.csv. If you're not familiar with CSV files, you can think of them as simplified spreadsheets—in fact, most can be opened with Microsoft Excel. As more beacons are transmitted, the file grows in size. When it reaches 32 megabytes—roughly the size of ten compressed music files—it can crash the flight system." Unfortunately, the only way to clear that CSV file is to reboot LightSail. It can be done remotely, but as anyone who deals with crashing computers understands, remote commands don't always work. The command has been sent a few dozen times already, but LightSail remains silent. The best hope may now be that the system spontaneously reboots on its own.

12 of 366 comments (clear)

  1. Seriously? by Anonymous Coward · · Score: 5, Insightful

    I’m usually the first to defend others when some bug like this makes it through testing. Hindsight always being 20/20, only takes one bug amongst a million good bits of code, etc. But this just seems like something that even basic testing should have caught.

    Did they not run this thing on the ground for a few weeks? That’s just basic testing, especially for something that is going to be inaccessible for a while. Also that some critical bit of processing relies on stuff being written (and then presumably read back from) a csv file is very worrying.

    This sounds like some very shoddy work.

    1. Re:Seriously? by Mr+D+from+63 · · Score: 5, Insightful

      Testing might have found it, but I'd say that regardless of testing they should assume something bad will happen with the software and have a mechanism in place to force reboot & update on a locked up system. Maybe they thought they did. Its a shame if they can't get it fixed.

    2. Re:Seriously? by harperska · · Score: 5, Informative

      One report I read made it sound like they were aware of the bug for a while. It's possible that they had to launch with an old version of the software because the patch wasn't ready yet, and being a secondary payload on a launch you have no say whatsoever as to the launch date. They probably expected to be able to upload the patch after launch, but the log filled up faster than expected.

      That being said, it is shoddy programming to blindly write to a log on a resource-constrained embedded platform (or any platform, really. Just especially so on something like this), so somebody definitely goofed. All I am saying is that it probably was caught by testing, but couldn't be fixed in time due to various constraints. It was a dumb move on the developer's part to not do enough diligence and to rely too heavily on QA in the first place.

    3. Re:Seriously? by itzly · · Score: 5, Funny

      Their current plan is to wait charged particles to affect electronics so that it forces a reboot.

      Watchdogs are for wimps. Real designers use supernovas in a distant galaxy to reset their boards.

    4. Re:Seriously? by mnooning · · Score: 5, Insightful

      As a retired QA guy, I can tell you that checking that no files can grow without bound is standard fare. Same with exercising all code for long periods of time, as you pointed out. That means there was not a single experienced QA guy on the team.

      By the way, CSV was the golden standard for many years. Given the tight compactness/memory budget that space projects have, CVS with it's small foot print might well be the logical choice.

    5. Re:Seriously? by gstoddart · · Score: 5, Informative

      No, csv sure as hell is NOT a Microsoft format.

      Comma-separated values is a data format that pre-dates personal computers by more than a decade: the IBM Fortran (level G) compiler under OS/360 supported them in 1967.

      This has nothing whatsoever to do with Microsoft, as much as you seem to want to blame them.

      --
      Lost at C:>. Found at C.
    6. Re:Seriously? by RavenLrD20k · · Score: 5, Funny

      Oh...you mean the 'C-x M-c M-supernova' command shortcut in Emacs, right?

  2. CSV by Anonymous Coward · · Score: 5, Insightful

    I know the average IQ at /. has gone down over the years, but I think the explanation of what a CSV file is is slightly too much dumbing down.

    1. Re:CSV by ArcadeMan · · Score: 5, Insightful

      I think the "32 megabytes—roughly the size of ten compressed music files" part is even more insulting.

    2. Re:CSV by ArhcAngel · · Score: 5, Funny

      Extended testing was one of the stretch goals. Sadly they never reached that tier.

      --
      "A person is smart. People are dumb, panicky dangerous animals and you know it." - K
  3. Re:What the computer needs is ... by plopez · · Score: 5, Insightful

    No. They need programmers and sysadmins that knew that they were doing. E.g. roll log files and/or put logs on a non-critical partition. Systems Administration 101 for systems where memory and disk space are at a premium. It was a rookie mistake.

    --
    putting the 'B' in LGBTQ+
  4. Updated Summary W/ Tech Terms Explained by cve · · Score: 5, Funny

    Last week a week is approximately the amount of time between new 'Keeping up with the Kardashians' episodes saw the successful launch of the Planetary Society's LightSail spacecraft, the solar-powered satellite that runs Linux Linux is like Windows for smart people and was crowdfunded on Kickstarter Kickstarter is a place to buy digital watches . The spacecraft worked flawlessly for two days, but then fell silent, and the engineering team has been working hard on a fix ever since. They've pinpointed the problem: a software software is like what you download from the app store glitch. "Every 15 seconds, LightSail transmits a telemetry beacon packet a telemetry beacon packet is like a tweet . The software controlling the main system board writes corresponding information to a file called beacon.csv. If you're not familiar with CSV files, you can think of them as simplified spreadsheets—in fact, most can be opened with Microsoft Excel. As more beacons are transmitted, the file grows in size. When it reaches 32 megabytes—roughly the size of ten compressed music files 32 MB is also approximately the size of 13 iPhone 6 selfies —it can crash the flight system The satellite's twitter feed blows-up ." Unfortunately, the only way to clear that CSV file is to reboot LightSail Like holding down the power and home buttons on your iPhone at once -- don't try this unless instructed by someone at the Genius Bar . It can be done remotely, but as anyone who deals with crashing computers understands, remote commands don't always work Like when Siri plays Billy Ray instead of Miley . The command has been sent a few dozen times already, but LightSail remains silent. The best hope may now be that the system spontaneously reboots on its own Like when drop your phone in the pool and it still works .