DALI 1.1 comments

[Steve Allen]

On Tue 2016-05-10T10:37:28 -0400, Arnold Rots hath writ:
> In astronomy we have no use for timezones, but use time stamps
> tied to specific time scales, one of which is UTC.
> Therefore we do not need the 'Z'.
> We do need to be explicit in our specification of time scale and
> should attach that label to all our time stamps, implicitly or
> explicitly.
> Clearly, writing "2016-05-10T14:33:03Z (TDB)" would be insane.
> If, therefore, the 'Z' would either be allowed or required for all
> UTC time stamps, we would end up with two independent
> time scale designations, which is unwise, silly, and dangerous.

Yes, ISO 8601 is only a subset of what happens in astronomy, and
a subset of what is needed for time stamps in general.
Although there will be tremendous inertia, there is an effort underway
to produce a technical specification for machine readable time stamps
that also encode the particulars of the time scale being used
http://nwtime.org/projects/timestamp-api/
I agree with Arnold that despite the defaults built into current
date/time parsers it is not a good idea to add a Z.

--
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