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claviola | 3 years ago

Do you honestly consider modifying the core idea of the 24 hour day to be a "slight tweak"? I can't even imagine how many different things rely on that assumption.

(and I'm sorry, but what does "naming months and seasons in Mars" have to do with this?)

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wongarsu|3 years ago

You have basically three options for timekeeping on mars: adjust the day, adjust the second, or give up on days syncing with the (apparent) movement of the sun.

The first option breaks mostly assumptions made in software and processes, the second mostly assumptions made in hardware, and the third breaks human's circadian rythm (a 23 or 25 hour rythm isn't a big deal, but it has to sync to light).

Of those three, the things that rely on 24 hour days seem to be the easiest to change. Though there is precedent both to messing with the length of a day (a leap second makes the day one second longer, making 23:59:60 a valid time) and the length of a second (google pretends like seconds are slightly longer as an alternative way to deal with leap seconds)

claviola|3 years ago

I must have missed something. This article is about the Moon.

yrro|3 years ago

The very first entry on the list of falsehoods programmers believe about time[0] is that there are always 24 hours in a day.

[0] https://gist.github.com/timvisee/fcda9bbdff88d45cc9061606b4b...

23:59:60 happens when we add leap seconds to the clock, for instance...

claviola|3 years ago

I wasn't talking about software development by itself, but human behaviour.

cornholio|3 years ago

> and I'm sorry, but what does "naming months and seasons in Mars" have to do with this?

Time of day and calendaring and discussed together because they allow you to ask things like "what was the date and time on Mars prime meridian on Feb 2 2023 6:00 UTC" and get a recognizable date and time back. It's essentially a timezone, albeit a very strange one with a variable offset.

> modifying the core idea of the 24 hour day to be a "slight tweak"?

Ok, maybe an exaggerated hand-wave on my part. It's a slight software tweak on my desk clock. I was contrasting with the alternative of modifying a fundamental SI unit and more or less rebuilding from scratch all hardware sent on Mars. The fuckups alone resulting from confusing Earth seconds with Mars seconds.

skissane|3 years ago

For software that runs on Mars, I think "Mars date/time" has to be a brand new set of APIs and data types. The existing date/time APIs/types are for Earth times only. The "local time zone" on Mars would just be UTC. That way there wouldn't be much possibility of bugs based on confusing Earth and Mars time scales – all pre-existing software would still work with Earth date/times, and anything that needed to deal with Mars date/times specifically would have to be modified to handle them.

RedNifre|3 years ago

No, Mars has less mass than Earth, so if you use Earth UTC, Mars seconds will be longer than SI seconds, which does not seem like a good idea.

manojlds|3 years ago

cough leap second cough

claviola|3 years ago

Sure, the leap second is a thing. We still represent the day as 24 hours for humans. They didn't seem to be talking about an "under the hood" hand waving of a significant part of the day.

jjk166|3 years ago

Way easier than changing the rotation speed of mars.