Re: Fixing POSIX time

2006-01-20 Thread Clive D.W. Feather
Neal McBurnett said: UT1:Flamsteads birthday ? Cute. 1646-08-19 O.S. or N.S.? At least it wasn't January, which would have added a third option. -- Clive D.W. Feather | Work: [EMAIL PROTECTED] | Tel:+44 20 8495 6138 Internet Expert | Home: [EMAIL PROTECTED]

Re: Risks of change to UTC

2006-01-20 Thread John Cowan
Rob Seaman scripsit: Only a minority (small minority, one would think) of systems currently include any DUT1 correction at all - although these will perhaps tend to be the most safety-critical applications. [...] That is, of course, one of the major issues for astronomers - we rely on UTC

Re: Risks of change to UTC

2006-01-20 Thread Neal McBurnett
On Fri, Jan 20, 2006 at 03:12:15PM -0500, John Cowan wrote: Rob Seaman scripsit: Only a minority (small minority, one would think) of systems currently include any DUT1 correction at all - although these will perhaps tend to be the most safety-critical applications. [...] That is, of

Re: Risks of change to UTC

2006-01-20 Thread James Maynard
In reply to Rob Seaman, John Cowan wrote: Seaman: [A]s clock time diverges further and further from solar time, more systems in more communities (transportation, GIS, innumerable scientific disciplines, what have you) would be revealed to need remediation. Cowan: Can you spell out some of

Re: Risks of change to UTC

2006-01-20 Thread M. Warner Losh
In message: [EMAIL PROTECTED] James Maynard [EMAIL PROTECTED] writes: : ones position using sight reduction tables. Today a mechanical watch or : chronometer, or a battery-powered wristwatch, can be set to UTC using : radio time signals. Then when power fails, the sailor still has a :

Re: Risks of change to UTC

2006-01-20 Thread John Cowan
Neal McBurnett scripsit: To sum it up, PLEASE don't fundamentally change the DEFINITION of UTC, or you risk whole new kinds of confusion. Hopefully by now the folks on this list that don't like leap seconds at least have agreed that any change should be to a new time scale like TI, and

Re: Risks of change to UTC

2006-01-20 Thread John Cowan
James Maynard scripsit: Small boats, sea water, and electrical systems don't mix very well. The damp, salty environment all too often leads to failures of a boat's electrical system. A prudent sailor should not rely for navigation only on electrically powered systems like GPS or loran. Your

Re: Risks of change to UTC

2006-01-20 Thread James Maynard
M. Warner Losh wrote: In message: [EMAIL PROTECTED] James Maynard [EMAIL PROTECTED] writes: : M. Warner Losh wrote: : In message: [EMAIL PROTECTED] : James Maynard [EMAIL PROTECTED] writes: : : ones position using sight reduction tables. Today a mechanical watch or :

Re: Risks of change to UTC

2006-01-20 Thread James Maynard
M. Warner Losh wrote: : If DUT1 is broadcast, then one can set the time keeping device to UT1 : by a means similar to setting it to UTC, even if DUT1 exceeds 0.9s : with a similar accuacy (or better). There's nothing that says a watch : has to display UTC to be set correctly. You seem to

Re: Risks of change to UTC

2006-01-20 Thread Brian Garrett
- Original Message - From: James Maynard [EMAIL PROTECTED] To: LEAPSECS@ROM.USNO.NAVY.MIL Sent: Friday, January 20, 2006 9:33 PM Subject: Re: [LEAPSECS] Risks of change to UTC M. Warner Losh wrote: In message: [EMAIL PROTECTED] James Maynard [EMAIL PROTECTED] writes: :

Re: Risks of change to UTC

2006-01-20 Thread M. Warner Losh
In message: [EMAIL PROTECTED] James Maynard [EMAIL PROTECTED] writes: : M. Warner Losh wrote: : : : If DUT1 is broadcast, then one can set the time keeping device to UT1 : : by a means similar to setting it to UTC, even if DUT1 exceeds 0.9s : : with a similar accuacy (or better).