[time-nuts] Positional accuracy of the M12+T

[Rex]

On Thu, 04 Jan 2007 10:42:13 +0000, "Poul-Henning Kamp"
<phk at phk.freebsd.dk> wrote:

>In message <tclpp21ov2sg7gt15qu13gi8lugb4sm60b at 4ax.com>, Rex writes:
>>On Thu, 04 Jan 2007 10:07:11 +0000, "Poul-Henning Kamp"
>><phk at phk.freebsd.dk> wrote:
>>
>>>>You say, "the ellipsoide actually isn't one".  I don't understand what
>>>>that might mean. Care to elaborate?
>>>
>>>It is not an ellipsoide, it is some other weird ballon-animal shape.
>>>
>>
>>So, I think the ellipsoid is our best way of describing the rotational
>>approximation of the world vs a simple sphere. I guess you are saying
>>that the real shape of the world differs more in your area than in most
>>of the rest of the world from the ellipsoide model. Is that a correct
>>interpretation?
>
>Not the world, the envelope of uncertainty on the GPS position fix.

Ahh, that's to be expected and different from what I would have expected
relative to discussion of the ellipsoid. You mentioned ballon animals. I
assumed you must have meant the actual shape of the earth.

I am in no way smart enough to understand the actual math involved in
all the magic that gives us both incredible positions and times from
these satellites.

Technology keeps evolving, but this whole GPS satellite constellation
has to be the most amazing technology that can think of in my lifetime
AND that I have access to.

So many levels of finesse required in so many disiplines to be
coordinated to make it happen. Wow.