[LEAPSECS] drawing the battle lines

[Warner Losh]

On Mar 20, 2013, at 10:45 PM, Harlan Stenn wrote:


> So I gotta ask.

> 

> What's the problem with doing radar and other similar things in GPS time

> and keeping "human" time in UTC, with leap seconds?

> 

> I mean, sure, years ago timestamps were YYMMDDHHMMSS and those

> eventually got bigger, and eventually folks started noticing that things

> really got interesting twice a year jumping in and out of daylight

> savings time.

> 

> But doesn't that mean that we can solve the problem even better by

> making sure folks use timestamps that contain the timescale when that

> level of effort is useful?


Three things: (1) Leap seconds are rarely done correctly, and even when done correctly come at a cost that is disproportionate to their value. (2) You can know GPS time without knowing UTC, but not vice versa, since you have to know the GPS UTC offset, which isn't knowable until after the first almanac download, especially for a cold GPS receiver. (3) There will be much confusion as the two type of time are mixed.

Note that there is no daylight savings time in UTC, so that part of the argument can be  ignored.

Warner