Requiem for Relativity

On the topic brought up by Michiel: "speed of light is the same for all observers (and in all directions)".

This statement goes back to the interpretation of the Michelson-Morley experiment:
en.wikipedia.org/wiki/Michelson%E2%80%93Morley_experiment

The picture on this Wikipedia page: "A depiction of the concept of the "aether wind"" is fundamentally different from the model used to explain the planetary aberration which starts from a depiction whereby the light carrying medium rotates around the Solar System and whereby the planets move along with this light carrying medium with exactly the same speed (so without the planets dragging the medium or vica-versa).

Using this 'alternative depiction', it is logical that speed of light is the same for all observers (and in all directions).

At the same time, it is logical that it is possible to measure the Earth rotation through the Michelson Gale experiment:
en.wikipedia.org/wiki/Michelson%E2%80%93...93Pearson_experiment

Bart, Is the bending of light in the Einstein gravity model adding to your curved light beam model? If you added your curve to the data we have from bent light from stars how much of the total would be caused by the curve? I'm assuming both effects are operating.

<b>[Bart] "The Moon (O) and observer (A) move with largely the same ..."</b>

I constructed my example so that observer A is stationary with respect to the incoming beam. It is observer B (on Earth, or in the rocket moving like Earth moves) that is moving almost as fast as Luna (or the rocket O). Observer C is moving just as fast as observer B, but in a retrograde orbit. This is why B and C see S out in front of where it actually is, with the same magnitude of angular displacement, but the opposite sign (from our third party perspective - from their first party perspectives, B anc C just see S "out in front" of where it ought to be).

And why A sees S with zero angular displacement. Right where it ought to be. Right where it actually is.

<b>[Michiel] "[aberration] depends solely upon the transverse component of the velocity of the observer ..."</b>

They are being a little lazy with their explanation, and as a result their claim is misleading. If it were literally true, aberration would be expressed in meters per second rather than in degrees or radians. Aberration is a function of two velocities, not one.

I suppose they phrase it as they do because the speed of light (the speed of the incoming wave) is the same for all observers.
This approximate formula works for just about anything, as long as the calculated angle is less than about 4 or 5 degrees. Bullets, arrows, water waves, protons, light waves, and so on.

<b>[Jim] "Does this effect generate a red shift in the spectrum of stars??"</b>

If you look in the direction of your motion, the stars will have a slight blue shift. If you then turn 180, those stars behind you will have a slight red shift. But if you look perpendicular to your line of travel (where we have been looking to measure angular displacement of the star S and other stars near-by) you will see no doppler effect.

BTW, when you do see the doppler shift of stars in front of you or behind you, you will see no angular displacement of those stars.

One or the other, but not both.


<b>[Bart] "Suppose the Earth would not be rotating ..."</b>

To keep Sol directly overhead all the time, Earth must rotate once per year. From Luna, Earth appears to always be in the same place in the sky, because Luna rotates once per month.

(S)

| |
| |
| | Medium static to S
.................................................................................
S_b | Medium static to B or A
\ S_a O
\ S_a O
\ | OOO S_c
\ |OOOOO /
\&lt;---OOOOOOO/
\ OOOOO/
\ OOO/
\ O/
&lt;-- B /
A /
C --&gt;

FIG 2 The left edge of O has just crossed the straight line between S and A

Assuming that B (simulating Earth) is static relative to the light carrying medium:
At the instant when the leading edge of O just crossed the straight line between S and A/B/C:
- Light for all three observers follows the path S_b -&gt; A/B/C and is therefore visible to all three observers
- B observes light coming from S_b and B observes the left edge of O from the direction of S_a
- A observes light as if coming from S_a and observes the left edge of O as coming from S_c
- C observes light as if coming from S_c and observes the left edge of O as coming from a position to the right of S_c

Assuming that A is static relative to the light carrying medium.
At the instant when the leading edge of O just crossed the straight line between S and A/B/C:
- Light hits O as a result of which none of the observers can see star S
- A observes the edge of O coming from S_a (behind which S is obscured)
- B observes the edge of O as coming from S_b (behind which S is obscured)
- C observes the edge of O as coming from S_c (behind which S is obscured)

So, independent of the direction of the light carrying medium:
- all observers A/B/C will either see S or not see S
- every of the observers A/B/C see light S coming from a direction that depends on their own motion

In other words: it does not help to move faster in an attempt to observe more stars behind the edge of moon ...
The reason being that the edge of the moon will be subject to the same amount of additional aberration as for the stars behind it.

"Reverse Occultation" of Venus

Previously I cited observations of Lunar occultation anomalies of Jupiter, the Galilean moons, and Uranus. These included what I called "reverse occultation", where Jupiter's disk showed in front of Luna. This is not the "oil drop effect". The overlap is typically about half the planet's disk: many arcseconds, much more than, say, two or three arcsecond "seeing" due to atmospheric scatter.

Rechecking the Astronomical Journal tonight (the indexes of all the issues on the shelf at Iowa State Univ., from the first issue, in 1849, through 1890) I find three reports of "reverse occultation" of Venus, involving two different observatories and two different occultations. The first is by J. Ferguson at the U. S. Naval Observatory, for the April 18, 1855, Lunar occultation of Venus, observed with the "large equatorial" (AJ 4:95, 1855). Ferguson reports: "8h39m10s (M. T. Washington) The planet was seen half its diameter within the limb of the moon, exhibiting no diminution of light or of magnitude, but showing as if it were on this, and not on the other side of the moon. 8h39m38s The first diminution of magnitude was apparent; the inside or cut edge being straight and well defined; the planet still showing as if projected on the surface of the moon."

Again for the April 24, 1860 Lunar occultation of Venus, Ferguson (AJ 6:107, 1860) says, "The planet was distinctly seen projected on the moon's dark surface, and, when it began to be eclipsed, the diminution of light was made by a circular line, inside the moon's limb and parallel to it. I had witnessed the same appearance at an occultation of Venus, 1855...".

A similar report for this 1860 occultation comes from Gloucester, Massachusetts by Tuttle (AJ 6:119): "At the immersion the planet appeared to advance nearly its whole diameter upon the dark limb of the moon." (Tuttle was using a famous telescope that formerly had been used by Hind in England for asteroid discovery at Bishop's Observatory, reported in the Monthly Notices of the Royal Astronomical Society, 1851.)

Addendum Dec. 5: For the 1855 occultation, Venus was 1.38 AU distant; the dark part of Luna was covering the lit part of Venus. For the 1860 occultation, the configuration was roughly the same, but Venus was only 0.83 AU distant.

If it was naked-eye visible in the mid 1800s, a CCD ought to give even better results. Recordable results, too.

What percentage of astronomical observations are routinely recorded these days?

How many reports like this have you seen? Is there a pattern of any sort that would allow us to predict when an occultation will turn "reverse"?

It might be an illusion, caused by the mind's ability to fill in (create) missing detail. Especially in low light conditions. Any evidence for or against this idea?

Have stars ever been observed 'behaving' like this?

===

Hmm. I wonder if there is a way to create a laboratory version of this?

LB