- From: Chris Lilley <chris@w3.org>
- Date: Wed, 9 Feb 2011 13:11:27 +0100
- To: John Cowan <cowan@mercury.ccil.org>
- CC: "Phillips, Addison" <addison@lab126.com>, Richard Ishida <ishida@w3.org>, www International <www-international@w3.org>
On Tuesday, February 8, 2011, 5:49:22 PM, John wrote: JC> Phillips, Addison scripsit: >> > It's essential that this be rewritten to take leap seconds into >> > account, as they say, early and often. >> Well, once or sometimes twice a year in certain years :-). JC> Current provisions allow for a leap second at the end of any month, JC> actually, and by the year 158421, we'll have to have a whole hour worth JC> of leap seconds every day. To put this in context; how many leap seconds have there been since the Jan 1970 epoch? In other words, if two date-times are subtracted, one from now and one right at the epoch, without accounting for leapseconds, what is the total error currently? OK, answering my own question http://en.wikipedia.org/wiki/Leap_second 24 seconds. And the time from atomic clocks differs from UTC by an additional 10 seconds, apparently. So the total error from ignoring this is half a minute and counting. -- Chris Lilley Technical Director, Interaction Domain W3C Graphics Activity Lead, Fonts Activity Lead Co-Chair, W3C Hypertext CG Member, CSS, WebFonts, SVG Working Groups
Received on Wednesday, 9 February 2011 12:11:31 UTC