[time-nuts] Determination of the placement of the first pps

[Poul-Henning Kamp]

In message <CABbxVHtyRBAQY8tLVDxxsVKjMLVF8LzgCn1q266yBMY9f13Bsw at mail.gmail.com>
, Chris Albertson writes:

>The Earth's rotation is always refferenced to a larger reference frame
>of distant stars, not the sun.

It's actually distant quarsars, and the point being that they are so
far away that any cross-field motion they might or might not have
would not represent a parallax error in our measurements of their
posisiton.

The measurements are done with VLBI, which is a good google search
to learn more about this.


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