Re: questions about UTC time, definitions, leap seconds, and measurement.

In article <BEBD4018.7B49%rbj@xxxxxxxxxxxxxxxxxxxx>, robert
bristow-johnson <rbj@xxxxxxxxxxxxxxxxxxxx> writes:

> by 1983, they must have expected about 1 leap second each mean year (1 part
> per 31556952) why didn't they define the second to be that much longer (say
> 9,192,632,060 cycles instead of 9,192,631,770 cycles of this cesium
> radiation? they would still have to add or subtract leap seconds
> occasionally, but much less often than they did in the late 20th century.
> why not, when you're *defining* the standard of time (with a much better
> standard), make that initial definition agree as much as possible with the
> known astronomical unit, and then stick to it?

Backwards compatibility. For a time, the second was defined as a
certain fraction of the year 1900; the atomic-time definition probably
was set up to ba as close as possible to this.

.

Relevant Pages

  • Re: Rule against Circular Dependencies?
    ... The subject of circular dependencies between classes has ... Why are you writing a OO design standard, if you are unsure of what ... Who's going to give a waiver if nobody knows if the rule should be ... Cycles are generally bad. ...
    (comp.object)
  • Re: 66MIPS 8bit microcontroller
    ... with hardware IEEE floating point support runs almost 3x faster than ... a standard 8051 computing a mandelbrot pattern. ... cycles for one floating point operation. ...
    (comp.arch.embedded)
  • Re: Unlucky and Imperial...
    ... Metric threads have a 60 degree included angle, whereas BSP has a 55 degree Whitworth form one ... the British Standard Cycle thread was used worldwide for cycles and motor cycles. ...
    (uk.rec.walking)
  • questions about UTC time, definitions, leap seconds, and measurement.
    ... i've been looking into the NIST site on their standard expression of the ... 9,192,632,060 cycles instead of 9,192,631,770 cycles of this cesium ... they would still have to add or subtract leap seconds ... when you're *defining* the standard of time (with a much better ...
    (sci.physics.research)
  • Re: 66MIPS 8bit microcontroller
    ... a standard 8051 computing a mandelbrot pattern. ... Given that they also say "up to 100 MFlops", I suspect they're comparing with/without the hardware IEEE on the same ... A quick look at the datasheet shows that a floating point operation takes ... cycles for one floating point operation. ...
    (comp.arch.embedded)