On May 24, 2006, at 6:27 AM, Zefram wrote:
> I've written a Perl module that handles the conversion between TAI and
> UTC. It's Time::UTC, available at <http://search.cpan.org/~zefram/>.
> When asked about future times where it doesn't yet know the
> leap second schedule, it automatically downloads and parses
> <http://maia.usno.navy.mil/ser7/tai-utc.dat>. This works well if
> there's
> a future leap second already scheduled, but otherwise there is a
> problem
> in working out how far ahead the last TAI-UTC offset applies.
Note that in a leap-secondless alternate reality, exactly the same
issues
would be encountered when trying to predict UT1 given TAI (or its
evil kirk
twin, "new-UTC").
> Amusingly, in the long run this will become a non-problem on its own.
> In perhaps a century or so it will become unavoidable to schedule
> more than one leap second ahead. That way the final time mentioned in
> tai-utc.dat will always be in the future.
Non-amusingly, in the alternate no-time-of-day universe, this never
becomes a non-issue for recovering the orientation of Earth-2.
Rob Seaman
National Optical Astronomy Observatory
Received on Tue May 30 2006 - 16:12:20 PDT