Interest in Timezone Information at JPL

Dave Skinner dave at
Wed Feb 26 18:24:51 UTC 1997

I guess I should be added to at least the tz-requests mailing
list and possibly the tz mailing list as well if it does NOT
include the former email addresses by default.  I represent
the only person at the Jet Propulsion Laboratory who has both
an abiding interest in these matters as well as an immediate
and on-going need for this information.

For the record, I am coding a web-based capability to look up
the latitude and longitude of any any geographic name that is
being maintained in the

web site, which is the National Imagery and Mapping Agency
(NIMA) GEOnet Names Server for non-US geographic names, and
at the

web site of the US Census Bureau, which is the name server for
US geographic names.  Once, I have the laititude and longitude
I am currently planning to find out which of your timezones
is the timezone associated with either the country or territory
involved or, if the country in question has multiple timezones,
to ascertain which of these timezones is the correct one based
on the associated latitude and longitude.

Finally, I plan to maintain and use your timezone information
to find the best estimate of time-of-day at that location for
a specified julian date.  I say "best estimate" because many of
our lookups will necessarily be for future events, and the
timezone boundaries, their associated offsets from GMT, and
especially their associated daylight savings time rules are
obviously only as good as we know them today.

The only problem that remains to be solved is the polygon
information that is currently burried in the

file.  To automatically lookup which timezone is associated with
a given latitude and longitude requires having those polygons.
So, I plan to see if the CIA Publications types would be willing
to post such a file.  If not, I may be forced to beat on the
gif file.

Anyway, it is really great to see that such a thorough effort to
identify and maintain timezone information is occurring.

Dave Skinner
dave at

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