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A comment on Europe pushing for lunar time zone. Parent comment

Re:Europe pushing for lunar time zone by jxf on Thursday March 02, 2023 @12:21PM (#34998683)
> Wait, what? TAI is the one time standard that doesn't change. It's just a bunch of atomic clocks averaged together. As monotonic as human kind is able to manufacture, at this time.

That is not the complete story. The calculation used to average the clocks has changed over time, thus amending TAI. The "perfect monotonic" time you're talking about is TT (terrestrial time), not TAI.

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Re:Europe pushing for lunar time zone by yencabulator on Thursday March 02, 2023 @12:42PM (#34999019)
Wikipedia about TT: "It is a theoretical ideal, and real clocks can only approximate it. [...] TT is indirectly the basis of UTC, via International Atomic Time (TAI)."

So, TAI is what we are able to measure. TT is a theoretical construct. Can't run computers on TT, can run them on TAI.

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Re:Europe pushing for lunar time zone by jxf on Thursday March 02, 2023 @12:54PM (#34999199)
Yes, I'm just saying that it's not accurate that "TAI doesn't change". It has notably and significantly changed a number of times.
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