Re: [LEAPSECS] 24:00 versus 00:00

From: Rob Seaman <seaman_at_noao.edu>
Date: Fri, 17 Feb 2006 09:56:23 -0700

Clive Feather wrote:

> London Underground does print 24:00 on a ticket issued at midnight,
> and in fact continues up to 27:30

An even better example. We cannot expect to dissuade such usage.
Deploying systems that require it be avoided is folly. Wouldn't
think the modulus operator would be controversial.

John Cowan wrote:

> Airlines in the U.S. [...] avoid arrival or departure times of
> midnight so that there is no ambiguity

Again - an even better example. The easiest way to conform to a
standard is to avoid challenging situations. It is trivial for
airline schedules to avoid a brief window around midnight - say,
23:59-00:01, or 2 out of 1440 minutes per day. It should be even
easier for NTP and other UTC transport mechanisms to avoid 2 minutes
out of 365+ days.

This isn't the solution to every challenge facing civil time - but it
sure simplifies the search space.

Rob Seaman
NOAO
Received on Fri Feb 17 2006 - 08:56:50 PST