Re: precession of mercury

On Dec 18, 3:09 pm, hw@..(Dr. Henri Wilson) wrote:

What the hell are you talking about? Stellar aberration has little or nothing
to do with Hipparpcos distance measurements. The angular change over six months
is obviously not light speed dependent. You are proving to be as moronic as the
rest of the EPG. I am very disappointed in you Paul...

I'm wondering what the hell YOU are talking about!

Variable stellar aberration due to variable speed of light would
have made Hipparcos's mission goals impossible.

Hipparcos's primary mission was to obtain positions, parallaxes,
and proper motions of all stars magnitude 13 or brighter.

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Consider nearby star x and distant star y at the North Ecliptic
Pole:

a a'
| |
| |
| |
| |
| |
-x- y
| |
| |
| |
| |
| |
b b'

-----
/ \
| |
B O A
| |
\ /
-----

With Earth at position A in its orbit, star x has a maximum
parallax shift to the left and a maximum aberration shift upwards,
so its apparent position in the sky is at point a. Star y has a
negligible parallax shift but the same aberration shift upwards,
so its apparent position in the sky is at point a'.

With Earth at position B in its orbit, star x has a maximum
parallax shift to the right and a maximum aberrational shift
downwards, so its apparent position in the sky is at point b.
Star y has a negligible parallax shift but the same aberration
shift downwards, so its apparent position in the sky is at point
b'.

With x and y in the same narrow field of view, and using y as a
reference, the parallax displacement of x appears as follows:

a-x-b y

The situation is more complex with stars away from the north
pole of the Ecliptic, but you get the idea. For all stars, the
apparent displacement of the star due to aberration is vastly
greater than the apparent displacement due to parallax. The
maximum angle of displacement due to aberration is about 20.626",
while the parallax of Proxima Centauri is 768.7+/-0.3 mas.

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Stars x and y have the same aberration shift provided that the
speed of light is constant c. But suppose the speed of light is
not constant. Suppose the speed of light from the star is c+v,
where v is the radial velocity component of the star's motion
towards Earth?

The radial velocity of the stars near to Earth (within 100 ly)
ranges about +/- 300 km/s, and the range of radial velocities
increases the further way you consider the stars.

Suppose nearby star x is 50 parsec away, so its parallax shift is
20 mas. Assume that distant star y is moving away from the Sun at
500 km/s, so that the speed of light towards the Sun is, by BaTh
theory, 299500 km/s. The maximum displacement due to aberration
would, in this case, be 20.661".

With x and y in the same narrow field of view, and using y as a
reference, the "parallax" displacement of x would appear as
follows, with the vertical displacement being about twice the
parallax displacement:

b
/
x y
/
a

The more distant stars one chooses as reference, the more
confusing and nonsensical the measurements get, because the
distant stars all have different radial velocities and would
display different amounts of aberration.

Since Hipparcos did not experience any such difficulties in
measuring stellar parallax, BaTh is disproven.

Jerry
.

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