On Fri, Nov 20, 2015 at 12:16 AM, Random832 <random832@fastmail.com> wrote:
On 2015-11-20, Paul Ganssle <paul@ganssle.io> wrote:
At least they seem to be deferring decision rather than actively deciding in favor of leap seconds. Still, is anyone actually advocating in favor of leap seconds? Who is being helped by keeping mean solar time at noon UTC or whatever the point of leap seconds is?
I got into an argument about this with ESR (in an NTPsec announcement thread on his blog) a few months ago and he said:
You think a timescale which is an integer number of seconds offset from TAI and which is within a second or so of London’s Mean Solar Time is wholly unnecessary. This demonstrates that you aren’t a marine navigator, an astronomer, or (where it bites especially hard) an aviator. It’s from these people that the real-world pushback against decoupling international standard time from mean solar is coming, and they have good reasons.
So, those people, I guess. It's still not entirely clear to me why they need civil time coupled to it, but there you go.
The only reason (at least, until UT1-TAI builds up to 2 or 3 hours) is celestial navigation using civil time, which should be good to half a km or so just using UTC clock time. Note, by the way, that the Navy is worried about hacks to the navigation infrastructure sufficiently to make celestial mechanics a required course once again at the Naval Academy. http://www.latimes.com/nation/la-na-celestial-navigation-20151025-story.html Regards Marshall Eubanks