[LEAPSECS] Get off my lawn!

Tom Van Baak tvb at LeapSecond.com
Sat Jun 18 12:31:36 EDT 2011

> This hasn't even been fully correct during the times when UT1 was

> observed with zenith telescopes (before about 1980). It is incorrect

> today -- all the seven parameters of Earth orientation are of course

> determined together, and UT0 is no longer needed nor used by anybody.

Are the details about UT1 correct in this link?

I ask because a number of posters claim UT1 is a measure of
earth angle. At one level this is true, of course, but if I read that
document correctly it says that certain periodic terms have been
removed from UT1. I think that's where the confusion arises -- it
makes UT1 seem more like it's trying to be a clock and less like
a precise measure of angle.

Perhaps you can clear up the mystery.


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