AFAIK The time of the Earth's rotation is not a constant, but is subject to the variable position of its inner iron-core relative to the Earth's geometric center. The closer this inner iron-core is to the Earth's center, the faster too is the Earth's rotation - else, the further it is from the Earth's center, the slower too is the Earth's rotation (as per the conservation of angular momentum).
On 02/11/2021 19:46, Mike Schwab wrote: > And I think adding a second inside a minute is a mistake. Seconds > 00-59, Minutes 00-59, Length of day dependends on the planet. An > Earth Day is usually 24:00.00 but can vary to 23:59:59 or 24:00:01, > used to be about 11 hours 4 Billion years ago. Earth days seem to be > longer by 1/3 of a second after 50 years of precise measuring, so > estimating a leap second every year after 150 years and 1 second every > day in 54,000 years. > > A Mars day is 24:37:00. People working with various Mars probes > arrive 37 minutes later each day since their work arrives from Mars at > that time. At least they don't get the jet lag when you have to > change shifts by 8 hours over a weekend. > > On Tue, Nov 2, 2021 at 4:33 PM Alan Altmark <[email protected]> wrote: >> On Tue, 2 Nov 2021 07:51:00 -0500, Paul Gilmartin <[email protected]> >> wrote: >> >>> On Tue, 2 Nov 2021 11:46:56 +0100, Stefan Skoglund wrote: >>>> ... UTC never changes, it increases monotonically ... >>>> >>> Those two statements contradict each other. And both are >>> incorrect. UTC falls back at a leap second. >> Nope. There is no fall back for leap seconds. They are *inserted* into the >> time stream (Temporal Mechanics 101). When that happens, UTC goes from >> 11:59:59 to 11:59:60 to 00:00:00. It doesn't pause, repeat, or go >> backwards. How an OS translates that concept into its local clock is left an >> exercise to the vendor.bbbbbbbbbbbb >> >> Alan Altmark >> IBM >> >> ---------------------------------------------------------------------- >> For IBM-MAIN subscribe / signoff / archive access instructions, >> send email to [email protected] with the message: INFO IBM-MAIN > > ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
