No. The standards of time interval are atomic, not linked to the Earth's rotation. Hence Leap Seconds.
-John ============== > Jim, > > It is my understanding that the government standard offices around the > globe, like NIST, calculates time by the earths rotation, I guess you > could > say, the old way, or using astronomy, but with this, they use things like > the decay factors of atomic materials to keep this time. If I recall, > things had to be recallibrated after the earthquake at Japan, as it > changed > the earths rotational speed a very minute amount. Its kind of like, which > came first, the chicken or the egg on the standards. > > Best, > > Will > > *********** REPLY SEPARATOR *********** > > On 7/14/2011 at 12:26 PM Jim Palfreyman wrote: > >>Hi All, >> >>I've just realised I don't understand something. Something quite basic. >> >>Primary Standards are ones which don't have to be calibrated against > others. >>My understanding is that Caesium and Hydrogen masers are Primary >> Standards >>(in our field). >> >>Secondary Standards are calibrated against the Primary Standards. My >>understanding is that Rubidium is an example of a Secondary Standard. >> >>So I can calibrate my Rubidium clocks by adjusting the C Field. All good. >> >>But why is it that Caesium Clocks and Hydrogen Masers have an adjustment >>facility? >> >>And what about the clocks used to determine UTC around the world? Do they >>have an adjustment facility? What are they adjusted to? Wouldn't that >> make >>them Secondary Standards? >> >>Now I'm aware that the "average" of those clocks is UTC, so are those > clocks >>adjusted regularly to get closer to that average? >> >>I'm sure someone can clear this up for me. >> >>Regards, >> >>Jim >>_______________________________________________ >>time-nuts mailing list -- [email protected] >>To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >>and follow the instructions there. >> >>__________ Information from ESET Smart Security, version of virus > signature database 5851 (20110206) __________ >> >>The message was checked by ESET Smart Security. >> >>http://www.eset.com > > > > > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
