On Wed 2018-03-21T08:51:37-0700 Steve Allen hath writ: > Our robotic telescope with small FOV on the guider does better if it > is given UT1 to 0.1 second. That telescope grabs the USNO predictions > of EOP every week to update the pointing.
I'll add that I do not see any place where I would want to use UT1 via NTP for astronomical observations. The real-time operation of the telescopes does not want to be dependent on a very small number of external real-time sources over telecomm links that can fail. That is why we rely on the USNO predictions, for they give us several months of lookahead. Thus also we have several months of warning if the USNO decides to stop publishing EOP, and that is enough time to engineer a replacement source of information. It was not happy when DoD was doing theater-level jamming near Hawaii and the Keck telescope GPS time servers had dates that were completely insane. In that case the local system clocks retained sanity for the duration of the jamming. In extension of all this I argue again that what is really wanted is a source of Atomic Time that is completely robust plus a widely disseminated source of tabular or polynomial predictions of Atomic Time minus Universal Time. -- Steve Allen <[email protected]> WGS-84 (GPS) UCO/Lick Observatory--ISB 260 Natural Sciences II, Room 165 Lat +36.99855 1156 High Street Voice: +1 831 459 3046 Lng -122.06015 Santa Cruz, CA 95064 http://www.ucolick.org/~sla/ Hgt +250 m _______________________________________________ LEAPSECS mailing list [email protected] https://pairlist6.pair.net/mailman/listinfo/leapsecs
