# FW: Longitude/Latitude to TIME zone

Alan Pritchard apritchard at cix.co.uk
Fri Jun 2 12:20:00 UTC 2000

```I'm sorry, but this just not true, and is very misleading.

Longitude is, at best, only a /very/ broad indicator of the time zone. If your message was true, then you (in Australia) would not have the
Broken Hill situation, and SA & NT would be on +9 (and not +8:30).

The actual pattern of time zones is fundamentally based on countries and provinces. In fact, in real-life time zone terms, I think that I
would go so far as to say that the 15 degree boundaries serve no useful purpose whatsoever.

Best wishes
Alan Pritchard
The GLOBAL GAZETTEER: the world on file
http://www.allm-geodata.com
Tel: +44 (0) 1202 417 477

> > -----Original Message-----
> > From:	Muhammad Safeer [SMTP:msafeer at khi.compol.com]
> > Sent:	Thursday, June 01, 2000 7:47 AM
> > To:	tz at elsie.nci.nih.gov
> > Subject:	Longitute/Latitute to TIME zone
> >
> > Is there any formula to convert Longitute/Heading to time zone.
> >
> > Regards.
> >
>
>
> I'm not sure what "heading" has to do with it. Is that the direction in
> which travel is proceeding? If so, it doesn't affect your "time zone".
> Only
> longitude affects that. You can calculate your actual mean-solar-time
> offset from Greenwich in hours simply by dividing your longtude in
> degrees
> by 15. For longitudes east the answer is in hours ahead of Greenwich and
> for longitudes west the answer is in hours behind Greenwich. If you
> want to
> calculate the nearest whole-hour time zone offset, you can simply round
> the
> answer from the previous calculation to the nearest hour. For example, I
> live and work at longitude 151 degrees and about 15 minutes east. That
> means the time by the sun here is 10 hours and about 5 minutes ahead of
> Greenwich. The nearest whole-hour time zone offset is thus 10 hours
> of Greenwich.
>
> --Alex
>
> _______________
> Alex LIVINGSTON
> Macintosh and Lotus Notes Support / Information Technology (IT)
> Australian Graduate School of Management (AGSM)
> UNSW SYDNEY NSW 2052 / Australia
>
> Facsimile: +61 2 9931-9349 / Telephone: +61 2 9931-9264
> Time     : UTC+11---[last Mar. Sun.---UTC+10---[last Aug.
> Sun.---UTC+11---
>
> At midday today, Friday, June 2,
>   time since epoch (1-1-1 at 00:00:00) is
>     730272.5 days = 1999.41819476 average Gregorian years
>   time until 3rd millennium, 21st century, 201st decade, 2001st year is
>     212.5 days = .58180524 average Gregorian years
>
>

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