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    Current / future state of UT1 access?
    From: Paul Hirose
    Date: 2018 Mar 16, 11:24 -0700

    Another recent contribution of interest from the LEAPSECS list:
    -------- Forwarded Message --------
    Subject: 	[LEAPSECS] current / future state of UT1 access?
    Date: 	Fri, 16 Mar 2018 10:18:11 -0700
    From: 	Rob Seaman 
    Reply-To: 	Leap Second Discussion List 
    To: 	leapsecs{at}leapsecond.com
    Regarding Demetrios's response to Steve: did astronomers give advice
    divergent to what CCIR decided?It isn't obvious how the history of this
    rather typical, if somewhat esoteric, technical debate amounts to
    "strong emotional bias". I reject the implication that technical
    disagreements, at that time or in the current day, are nothing more than
    It is perhaps telling that Demetrios doesn't address Steve's central
    assertion that it was recognized early on that two kinds of time were
    needed. Two kinds of time are still needed.
    Meanwhile, over the past week or two I have not been able to connect to
    NIST's UT1 server:
    Judah Levine has been very helpful in looking at things on the NIST
    side, and Harlan Stenn and Martin Burnicki have been insightful
    regarding NTP. Needless to say, this level of expert customer support is
    atypical! There is no reason to believe that NIST cannot serve UT1, and
    certainly such a brain trust (absent my fumble-fingers) could oil the
    gears and get the NTP clock spinning like a top. However, that is not
    currently the case from my campus. (We do see two other NTP servers in
    the same rack as that NIST UT1 server.)
    I'm preparing a paper on pragmatic timekeeping for an upcoming
    observatory operations conference and would welcome comments from
    anybody who has been using the NIST's UT1 service or any other UT1
    service or related internet tables. And those who maintain NTP instances
    might try connecting to at the University of Colorado in
    Boulder and report on their results.
    For many purposes (even in astronomy) UTC currently serves as a proxy
    for UT1 and for mean solar time in general. If leap seconds cease that
    approximation will no longer be functional and the engineering
    requirements and infrastructure for delivering UT1 will be stressed
    manyfold. How well does it work now? What investment would be needed to
    make it reliably scalable? Absent emotion, what are the proposed best
    practices for providing access to the multiple timescales needed?
    Many thanks!
    Rob Seaman
    Lunar and Planetary Laboratory
    University of Arizona

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