On Thu 2010-11-04T20:23:12 +0000, Michael Deckers hath writ: > Yes, you are of course right. My point is that even UT1 > does not try. Sidereal time is no longer an affine > function of UT1.
All forms of UT1 have been direct measures of earth rotation. One can argue about zero points and drifts, but the underlying purpose of UT1 is to monitor rotation with a value that tracks where the sun is over the earth. In that sense UT1 tries to be a form of mean solar time, so it merits a name consistent with the 1884 IMC "universal day" and the 1928 IAU "universal time". This is not the case with a purely atomic time scale uncorrected for the rotation of earth. To name that "universal time" is abuse. -- Steve Allen <s...@ucolick.org> WGS-84 (GPS) UCO/Lick Observatory Natural Sciences II, Room 165 Lat +36.99855 University of California Voice: +1 831 459 3046 Lng -122.06015 Santa Cruz, CA 95064 http://www.ucolick.org/~sla/ Hgt +250 m _______________________________________________ LEAPSECS mailing list LEAPSECS@leapsecond.com http://six.pairlist.net/mailman/listinfo/leapsecs
