this post was submitted on 21 Aug 2023
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Perhaps the 84 second burn overflowed the integer (2^6) and was caught by a 2^7s check (127s)

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[–] fiah@discuss.tchncs.de 31 points 1 year ago (2 children)

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 6 points 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 3 points 1 year ago (2 children)

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 3 points 1 year ago (1 children)

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 3 points 1 year ago (1 children)

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

[–] leviosa@programming.dev 0 points 1 year ago (1 children)

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 1 points 1 year ago (1 children)

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 -2 points 1 year ago (1 children)

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 1 points 1 year ago (1 children)

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

Found the Russian sympathizer though.

[–] leviosa@programming.dev 0 points 1 year ago* (last edited 1 year ago)

Even the phrase "Russian sympathizer" is propaganda. Simple messaging sinks in.

I just have an interest in the wars around the world that the West (the UK, USA, Israel, France) are magically omnipresent in and around. With of course completely coincidental geopolitical prizes to win, as 'we' play Team NATO World Police around the world after the first rounds of our Confessions of an Economic Hitman tactics fail. The same old players pop up in every new episode of their perpetual war plan.

This is another episode. All wrapped up in a completely independent narrative with a different cartoon mad man to fight and a nice humanitarian angle so that people get all emotionally attached and don't join the dots.

[–] ChrisLicht@lemm.ee 3 points 1 year ago (1 children)

Looking forward to T-18 sightings by this time next year . . .

[–] Millie@lemm.ee 1 points 1 year ago

Is that like a robot infant Arnold?

[–] colonial@lemmy.world 19 points 1 year ago (1 children)

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...

[–] intelati@programming.dev 4 points 1 year ago (1 children)

This is Roscosmos we're talking about here. First lunar mission in 25 years??

So it was, like, sitting in a garage collecting dust since 1997?

[–] IWriteDaCode@programming.dev 12 points 1 year ago* (last edited 1 year ago) (1 children)

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?

[–] intelati@programming.dev 2 points 1 year ago (1 children)

There's further discussion of possible explanations in the replies

[–] IWriteDaCode@programming.dev 5 points 1 year ago (1 children)

Ah I think it's Twitter's new thing where you can't see replies of your not logged in.

[–] TehPers@beehaw.org 3 points 1 year ago

Nitter link. This shows replies.

[–] 14th_cylon@lemm.ee 11 points 1 year ago* (last edited 1 year ago) (1 children)

what do we say to the god of software bugs ruining our space exploration? not today!

one of these days we will finally say it, but... not today 😆

https://en.wikipedia.org/wiki/List_of_software_bugs#Space

[–] wahming@monyet.cc 9 points 1 year ago (1 children)

Not today, because the date overflowed a counter somewhere.

[–] tiredofsametab@kbin.social 19 points 1 year ago (1 children)

Days since last timezone incident: -1

[–] ellenor2000@mastodon.top 3 points 1 year ago (1 children)
[–] TehPers@beehaw.org 1 points 1 year ago

When your timezone handling doesn't handle time dilation...

[–] ImpossibleRubiksCube@programming.dev 3 points 1 year ago (1 children)

On the bright side, India just did this, so we've got data coming from the poles after all!

[–] intelati@programming.dev 1 points 1 year ago

Yes! I was hopeful after the close failure a few years 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.

[–] ImpossibleRubiksCube@programming.dev -2 points 1 year ago* (last edited 1 year ago) (1 children)

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 1 points 1 year ago (1 children)

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).

Ah yes, I remember that one clearly. We were all pretty pissed off about it.