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    Re: NavList zone decriptions
    From: Frank Reed
    Date: 2011 Mar 18, 04:35 -0700

    That's Internet time zone styling. The specific number and the particular way that's composed comes from the computer that generated the email message or the message board post. You can convert any email time stamp to UT by flipping the sign on the zone offset and adding it to the nominal time. The date and time on this post (the one I'm replying to) is "Mar 18, 03:11 -0700" so you posted it as 03:11+07:00 or 10:11 UT which appears to be correct, though it's possible there's a "Daylight Saving Time" correction missing. You asked why your messages show -0700 or -0800. That's because you're posting from the message boards which means that the message is actually being distributed from a computer located somewhere else. I actually have no idea where that is physically but it's probably in California. I think you'll find that it switched from -0700 to -0800 last week when the US switched to DST.

    I considered converting all of our posting times to GMT/UT at one point but it's a bit more complicated than it sounds. The Internet, and email even more so, have grown up organically so many systems exist in parallel. Some email servers continue to use zone names, like "EDT", instead of the offset in hours. It doesn't seem worth the trouble to handle all the special cases.

    A general thought: the US definitely, and other countries presumably, are now on Daylight Time more than half of the year. We're all east of where we should be. This is part of a longstanding tendency for countries to move their time keeping further east. The boundary between Eastern and Central time zones in the US used to be in Pittsburgh, Pennsylvania. It gets quite extreme. Indiana and Michigan, for example are presently setting their clocks for most of the year to a time zone that would make sense at the eastern tip of Nova Scotia in Canada. That is, when the Sun is on the meridian in eastern NewFoundland, the clocks in Indianapolis and Detroit read "12:00" (on average). For most of the year, the Sun doesn't actually cross the meridian in these western parts of this area for another hour and three-quarters.


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