[geocentrism] Re: Two spin axes of Earth?
- From: Regner Trampedach <art@xxxxxxxxxx>
- To: geocentrism@xxxxxxxxxxxxx
- Date: Mon, 12 Nov 2007 10:26:14 +1100
The instantaneous distance to the Sun can be measured, and the orbit is found
to be an ellipse with the Sun at the Focal point (well, very slightly offset
from the focal point). The changing apparent diameter of the Sun is also a
direct observation of the orbit being elliptic.
The offset of the Sun-Earth centre of mass is insignificant compared to the
distance between the two focal points. In Fig. 2 you can see the distance
between the focal points (twice the offset between the ellipse and the circle,
whereas, the offset of the Sun-Earth centre of mass is 0.06% of the Solar
radius
which you cannot see on the scale of that plot. It can, of course still be
measured).
The orbit could of course be the same if the Sun orbited the Earth in an
elliptical orbit. But there are other "details" that are hard to explain.
Kind regards,
Regner Trampedach
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Quoting Jack Lewis <jack.lewis@xxxxxxxxxxxx>:
> Dear Regner,
> Thank you for your unexpected speedy reply!
> In essence the elliptical orbit of the Earth is determined not by direct
> observation but by indirect calculations of the centre of mass between the
> Sun and the Earth. It is also by measuring the Sun's changing diameter. Is
> there any reason why this phenomena would not also be the same for an
> orbiting Sun about the Earth? Dynamic equivalence perhaps?
>
> Jack
>
>
> ----- Original Message -----
> From: "Regner Trampedach" <art@xxxxxxxxxx>
> To: <geocentrism@xxxxxxxxxxxxx>
> Sent: Sunday, November 11, 2007 1:38 PM
> Subject: [geocentrism] Re: Two spin axes of Earth?
>
>
> > The Earth's orbit is an ellipse with a small eccentricity (deviation from
> > circle) of 0.0167 (circle is 0.0).
> > First of all; an ellipse has two focal points ("centres")
> > and a circle of course only has one. An ellipse can be drawn with two pins
> > stuck into the paper, and a loop of thread around both, pulling the loop
> > out to a triangle with your pen. Draw around the two pins with the loop
> > taught and the result will be an ellipse. For close pins and a long loop
> > you will get small eccentricity and close to an ellipse (small
> > eccentricity).
> > Second; the Sun-Earth centre-of-mass (about 450 km from the Sun's centre
> > only 0.06% of the Sun's radius) will be at one focal point (one of the
> > pins
> > in your drawing) of the ellipse described by the Earth's orbit. The two
> > focal points are symmetric about the actual centre of the ellipse. The
> > main
> > elliptical effect of a small eccentricity will be the offset by the focal
> > point. And I can assure you that the Earth orbit I plotted is not a
> > circle,
> > although it is close.
> > The Sun-Earth distance (the instantaneous radius of the Earth orbit) can
> > be measured directly by the parallax method from opposite sides of the
> > Earth.
> > Variation in the Sun-Earth distance can also be measured by observing the
> > change in apparent size of the Solar disk. The diameter of the orbit, on
> > the
> > other hand, cannot be measured, and also makes little sense when dealing
> > with
> > ellipses.
> >
> > Kind Regards,
> >
> > Regner Trampedach
>
>
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