[Bug 27253] New: Confusions involving Universal Time and old time stamps

https://www.w3.org/Bugs/Public/show_bug.cgi?id=27253

            Bug ID: 27253
           Summary: Confusions involving Universal Time and old time
                    stamps
           Product: HTML WG
           Version: unspecified
          Hardware: All
                OS: All
            Status: NEW
          Severity: normal
          Priority: P3
         Component: HTML5 spec
          Assignee: dave.null@w3.org
          Reporter: eggert@cs.ucla.edu
        QA Contact: public-html-bugzilla@w3.org
                CC: mike@w3.org, public-html-admin@w3.org,
                    public-html-wg-issue-tracking@w3.org

Created attachment 1534
  --> https://www.w3.org/Bugs/Public/attachment.cgi?id=1534&action=edit
Fix some confusions involving Universal Time and old time stamps.

The HTML5 spec requires UT1 for pre-UTC time stamps, but in practice
UT2 was the basis of civil timekeeping just before UTC was inaugurated,
and UT0 is a better choice than UT1 if you go back far enough.  But the
main point is that the HTML standard shouldn't try to impose a "must"
time standard here (UT1 vs UT2 vs whatever) when this doesn't correspond
to common practice.  Instead, the standard should simply call out
Universal Time as a general term.

A proposed patch is attached.

Some other minor changes for this edit:

* Change a couple of "must"s to "should"s when "must" is too strong.

* Mention that UT is mean solar time, not solar time.

* Don't require actual observations at Greenwich for old time stamps --
if you go back far enough, nobody was at Greenwich to observe anything.

My source for UT2 being the basis of civil timekeeping just before UTC is
the following email from Steve Allen of UCO/Lick Observatory:

http://mm.icann.org/pipermail/tz/2014-November/021867.html

He cites the Bulletin Horaire of the Bureau International de l'Heure,
March-April 1960, which is archived here:

https://plus.google.com/photos/112320138481375234766/albums/6078225731350227361

-- 
You are receiving this mail because:
You are on the CC list for the bug.

Received on Wednesday, 5 November 2014 21:22:51 UTC