[LEAPSECS] Schedule for success

Rob Seaman seaman at noao.edu
Mon Dec 22 20:56:37 EST 2008

Poul-Henning Kamp wrote:

> Rob Seaman writes:


>> Right. And human time is synchronized with mean solar time [...]


> What do you really mean by "Synchronized ?"

The sun rises, the sun sets. We care about this in innumerable ways.

Other than that, this is the precise issue we have been debating for 9

> The civil (and therefore human) time at any spot on the planet, is

> offset up to several hours from, and steps up to one hour, due to

> DST, relative to any kind of physically based solar time you might

> care to name.

Again see:


> You claim seems to be that this "synchronization" has to be nailed

> at the sub-second level ?

Over long periods of time, it has to average to near zero. Over short
periods of time it is better to manage the issue than to ignore it.

Uncontrolled secular trends (as proposed by ITU) are untenable. The
amplitude of periodic effects needs to be bounded. The duration
between "resets" (of whatever sort) should be short enough for
continuity of oversight. The mean of the waveform is mean solar time.

> Again, I have yet to see any sort of data backing up this tacit

> claim of yours ?

See above and included messages. The alternative is to believe that
humanity would put up with some bizarre civilization where day and
night don't matter.

1) understood without being openly expressed
2) silent; saying nothing
3) unvoiced or unspoken

Clearly this word has nothing to do with me :-)


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