Perhaps the 84 second burn overflowed the integer (2^6) and was caught by a 2^7s check (127s)

  • fiah@discuss.tchncs.de
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    1 year ago

    there’s no way engine burn time is graduated in seconds on a spacecraft in 2023, that’s way too coarse

    • 14th_cylon@lemm.ee
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      1 year ago

      i can see doing one burn that is kind of rough, then evaluating the situation and applying some correction?

    • Millie@lemm.ee
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      1 year ago

      Why do you expect the Russian space program to be using new equipment after the antique show of an invasion in Ukraine?

      • leviosa@programming.dev
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        1 year ago

        Every country uses a combination of older and newer equipment in any war. The war propaganda wizards just try to make things like that look unique to Russia.

        • Millie@lemm.ee
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          1 year ago

          I don’t think most countries are using first aid kits from the 70s.

          • leviosa@programming.dev
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            1 year ago

            I would take what our jingoistic media and talking heads say with a very large pinch of salt. It’s quite disrespectful to Ukrainian soldiers to say they’ve been facing an “antique show of an invasion”, not to mention Russian engineers. Propaganda aside, both sides have fought hard in what has been a very modern war.

            • Millie@lemm.ee
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              1 year ago

              I’ve more paid attention to Ukranians’ accounts of events than major media coverage. Lots of pictures of really old tanks being dragged away by farm equipment and other extremely dated supplies being found. If this is anyone’s propaganda it’s Ukraine’s, in which case I’m happy to participate.

              Nobody said it hasn’t been hellish for Ukraine, or that it hasn’t been a hard fight. Even if they were equipped with entirely WW2-era supplies, an invasion is an invasion, and by all accounts this has been a particularly cruel and brutal invasion.

              I really don’t care at all about being fair to Russian engineers at the moment.

              • leviosa@programming.dev
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                1 year ago

                If this is anyone’s propaganda it’s Ukraine’s, in which case I’m happy to participate.

                Why is that? It’s a blood bath and we shouldn’t support any propaganda that perpetuates wars.

                • Millie@lemm.ee
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                  1 year ago

                  Uhh, don’t think it’s the propaganda that’s perpetuating the war. That’d be the invasion.

                  Found the Russian sympathizer though.

  • colonial@lemmy.world
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    1 year ago

    Why in God’s name would you use a 6-bit signed integer for anything on a spacecraft? I know space-certified chips are pretty barebones, but surely not that bare bones…

  • IWriteDaCode@programming.dev
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    1 year ago

    The tweet you link didn’t indicate that. It said that an engine failure likely caused the overrun, running for 127 seconds instead of the planned 84. Why would something have a 2^7 int size check?

    Edit: Quoted

    The head of Roscosmos Yuri Borisov said that the main cause of the #Luna25 crash was an engine failure. Instead of the planned 84 seconds, he worked 127 seconds.

    Am I missing something?

  • Lil' Bobby Tables@programming.dev
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    1 year ago

    You know what this reminds me of? The processing failure that killed Phobos 2 right before it reached Mars.

    As I recall, the craft lost attitude control and didn’t have a safe mood to orient it toward the sun; so it burned through its batteries making adjustments in a few hours. It had two landing probes on board that never got to be used. So, no emergency backup systems. Never heard from it again.

    Of course this was 1989, and most people only had a vague idea what programmers did; but it still feels like a serious and kind of nebulous oversight.

  • Lil' Bobby Tables@programming.dev
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    1 year ago

    If Russia can humbly learn anything from this… it’s that they need to beat their programmers harder. Maybe deny them some rations.

    • athos77@kbin.social
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      1 year ago

      Mistakes happen. For example, may I introduce you to NASA’s 125 million dollar Mars Climate Orbiter, which spent most of a year traveling to the Red Planet before ignominiously burning up because a Lockheed Martin programmer decided to write the thruster-firing calculations in Imperial units (feet and pounds) instead of following the specifications to use metric units (meters and kilograms).