[LEAPSECS] Common Calendar Time (CCT) -Brooks Harris
Brooks Harris
brooks at edlmax.com
Fri Jan 17 19:43:32 EST 2014
On 2014-01-17 04:06 AM, Zefram wrote:
>> C) By declaring the anchor-point to existing TAI and UTC definitions
>> as 1972-01-01T00:00:00Z we have imposed an *uncompensated* Gregorian
>> calendar counting scheme on the proleptic part of the new timescale,
>> making 0000-01-01T00:00:00Z the origin of the new timescale.
> The proleptic Gregorian calendar is not limited in year range.
> Negative CE year numbers are valid, commonly used in astronomy, and ISO
> 8601 provides syntax for them. 0000-01-01 was preceded by -0001-12-31.
> There's no real origin here; the closest thing is the synchronisation
> point nominated by ISO 8601 at 1875-05-20 (the signing of the Convention
> of the Metre).
>
Yes, I understand that. Perhaps using the word "origin" was careless.
Maybe you can suggest a better term.
The point was to make it clear there is a "0000-01-01T00:00:00Z" "date"
on the new timescale, that dates earlier are negative, as you indicate,
and dates later are positive.
Of course the idea is that dates after 1972-01-01T00:00:00Z are "earth
corrected" (Leap Seconds). Application of "earth corrections" prior to
1972 as they are applied to the NTP "prime epoch" for example, will need
careful explanation.
-Brooks
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