BTW, this excellent question came to time-nuts yesterday; does anyone here have a definitive answer for Mike?
Thanks, /tvb ----- Original Message ----- From: <mflaws...@cox.net> To: <time-n...@febo.com> Sent: Tuesday, April 28, 2015 8:06 PM Subject: [time-nuts] Question about UT1 and the IERS Reference Meridian > Okay, I've tried to research this for a few days, and seem to be running > into conflicting data. > > Some articles say that UT1 is based on the IERS Reference Meridian (IRM). > Other articles say that UT1 is based on mean solar time at the Prime > Meridian (Greenwich). It can't be both! Which one is it? In other words, > which meridian would I need to stand on to indicate Solar Noon as > 12:00:00.000 (UT1) on a day of the year where the equation of time is 0 > seconds offset? > > From what I can reckon, a 200-400 millisecond difference exists between the > two longitudes, which are separated by about ~102 meters at Greenwich. So, > if UT1 (and hence UTC) is based on the IRM and not the Prime Meridian, then > at some point did clocks have to be adjusted ~200 milliseconds "away from" > the Prime Meridian when the IRM was defined? Or was it sloppy and they > treated the two as one and the same? > > Anyone know? _______________________________________________ LEAPSECS mailing list LEAPSECS@leapsecond.com https://pairlist6.pair.net/mailman/listinfo/leapsecs
