NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Time Zone Designations
From: Lu Abel
Date: 2017 Jan 3, 02:06 +0000
Better an imaginary zone -13 and UTC +13.
From: Lu Abel
Date: 2017 Jan 3, 02:06 +0000
Part of the +13 vs -13 issue could be what DATE. If you're just west of the date line your local time is UTC +12 (or zone -12)
But then what happens if you want to advance your clock an hour to observe daylight time? Would that put you in zone +11, the time zone 15 degrees east of you? That would mean you'd advance your clock by one hour and retard your calendar by one day!!
Better an imaginary zone -13 and UTC +13.
In a slightly different vein, one of the local TV stations in the San Francisco area noted that there was a flight that left Shanghai on Jan 1st but landed in SF on Dec 31st. Departed in 2017 and arrived in 2016!
From: David C <NoReply_DavidC@fer3.com>
To: luabel@ymail.com
Sent: Monday, January 2, 2017 5:43 PM
Subject: [NavList] Time Zone Designations
The subject of time just keeps growing and growing..........NZ is in time zone -12 ( Admiralty Manual of Navigation).When NZST is in use zone time is UTC + 12. When NZDT is in use zone time is UTC + 13. Currently NZDT is in use.When I have given details of an observation I have given my time as, for example, 13:43:56 (zone -13). Clearly that is incorrect as there is no zone -13. Should I give my time as:13:43:56 (zone -12, NZDT)13:43:56 (UTC + 13)13:43:56 (zone -13) because -13 is added to zone time to get UTC. This is the time zone sign convention.or some other format?
