[image] 12 noon So, a decade has ten years, counted as 1, 2, 3, 4, 5, 6, 7, 8, 9, 10. Seems to end with a zero, eh. Unless the CE started with a year zero instead of a year one, then decades, centuries and millenniums end with the end of the tenth year in that sequence. There are/have been va…

Here’s a good answer: [image] Start of a New Decade - Zero-based numbering and the Fence Post Problem The first decade, century or millennium started January 1, 0001 AD and ended on December 31, 0010 AD, 0100 AD or 1000 AD. Hence, our decade should start on January 1, 2021. However, what should…

on paper yes but when you digitze it, time gets made up with bits that need to fit the computer hence the fudge when you convert it back for humans to read it. Days months years decades and centuries make sense to us but its a all the same for a computer except when its programmed in 2 digit years… …

Not to mention the GPS system where the date (week number) rolls back to 0 every 1024 weeks (and much mayhem ensues!)

and the earth doesnt quite have a 24hr day so that has to be edited every few years. God should have been metric and all this would go away…lol

Hold on, what were we talking about? When a decade starts? First someone has to say what year system we’re talking about. GPS is based on the Julian year, which is based on the metric second, which is based on cesium. The display on all GPS units currently subtracts 18 seconds to align with siderea…

February 4, 2022 is day of year 35 in GPS Week 2195. If you want to be accurate the clocks in GPS satellites gets updated all the time as they are moving in space and trying to orbit the earth so they speed up and slow down effecting the time. Thats one of the corrections you pay for with subscrip…

[image] DeckApe: Hold on, what were we talking about? When a decade starts? First someone has to say what year system we’re talking about. I agree with this (in context) but if we want to get pedantic about this (and we do of course) than in practice people can usually determine what system…

[image] powerabout: Then you have zero longitude which is not at the line in Greenwich any more… I just learned that the other day. [image] Here's why the Greenwich Prime Meridian is actually in the wrong place Modern GPS has revealed the line used to calculate map coordinates an…

Only slightly off-topic … no matter what time system you prefer, MOL has opened an online shop to sell clocks and goodies removed by breakers. [image] MOL SHOP MOL, MOLSHOP, SCRAPPING, SHIP, SHIPSCRAPPING,SHIPACCESSORY, GIFT

Bowditch has an entire chapter named “ Time ” which I’m familiar with and I’ve been reading some historical stuff, for example a book about Copernicus but I couldn’t wrap my head around how the ancient astronomers could have figured out the things they did. So I built a big sundial from wood sticker…

Date and Time Systems

Scuttlebutt

Kennebec_Captain March 30, 2022, 1:20pm 2

Here’s a good answer:

Topic		Replies	Views
Start of a New Decade - Zero-based numbering and the Fence Post Problem Scuttlebutt	12	2698	January 7, 2020
12 noon Scuttlebutt	56	3096	March 30, 2022
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Date and Time Systems

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