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Planet X: SLOWING Rotation 1

In Article  <%OWR6.4337$> David Tholen wrote:
> By the way, the decision of when to insert a leap second
> is made by the International Earth Rotation Service, not
> the U.S. Navy.

The Navy seems to be very much in charge, and wanting to get rid of this
issue lately, too. This way, when the dawn starts coming later and
later, they can shoo people away from their door. Not my problem, etc.

   Dear Colleague,

   It has been proposed to change the definition of
   Coordinated Universal Time (UTC) regarding the
   insertion of leap-seconds, possibly even eliminating
   their use. Leap seconds are introduced so as to keep
   UTC synchronized (within 0.9s) to the time scale
   determined from the Earth's rotation.

   Should no new leap seconds be inserted, solar time
   will diverge from atomic time at the rate of about
   2 seconds every 3 years, and after about a century
   |UT1-UTC| would exceed 1 minute. Although no
   fundamental problems are anticipated, it is very
   likely that Y2K-like problems may result in
   software that assumes UT1=UTC, or |UT1-UTC|
   some value, or whose input/output records use a
   field size that can only accommodate |UT1-UTC|
   values up to one second.

   To gather information, an URSI Commission J
   Working Group was formed, consisting of Don
   Backer, Wim. N. Brouw, Barry Clark, Irwin
   Shapiro, Ir. E. Van Lil, and myself.

   We would like to ask you to consult with the
   members of your institute who currently deal
   with UT1-UTC, and give us a considered response
   to the following two questions:

    A. If the appropriate international bodies decide
       to eliminate the insertion of new leap seconds,
       would you foresee any practical problems for
       your institution/instrument/observations?

    B. Would you be in favor of such a proposal?

    C. Is there anyone else you would recommend
       we contact? (feel free to forward this eamil

    I would appreciate your assistance, and a response
    by January 15 [2,000] to

    I am attaching a list of institutions and persons
    contacted, except for 931 institutions whose
    emails were obtained from the AAS. I would like
    to apologize to anyone contacted twice, but also
    appreciate it if you would forward this email to
    anyone we have missed. Also, if you are an
    URSI Commission J national chair, we would
    appreciate your forwarding this email to your
    complete membership and in particular to the
    directors of observatories.

        Demetrios Matsakis,
        Director, Time Service Department,
        U. S. Naval Observatory
            Nov 16, 1999