Light velocity includes relative velocity proven by Io's Eclipses.

[LaurenceClarkCrossen]

"Light Speed and Special Relativity"
António Saraiva – 2009-09-13
https://www.gsjournal.net/Science-Journals/Research%20Papers-Relativity%20Theory/Download/2812

[LaurenceClarkCrossen]

Post by LaurenceClarkCrossen
"Light Speed and Special Relativity"
António Saraiva – 2009-09-13
https://www.gsjournal.net/Science-Journals/Research%20Papers-Relativity%20Theory/Download/2812

Just look at his graphs at the end.
"Approximately 100 years have passed since the theory of Special
Relativity (SR) appeared in
1905. The SR postulate that the velocity of light is constant in all
inertial systems implied the
necessity to revise the ideas of length, time and simultaneity. The data
provided here indicates
that this postulate is not compatible with the actual characteristics of
light. This empirical data
demonstrates that the speed of emitted light is isotropic and at c in
relation to the source, and
the observed light speed will be modified depending on the relative
motion of the observer and
the source. Newton's, Faraday's and Maxwell's concepts of physical
systems, length, time,
simultaneity, radiation and energy remain unchanged when the system of
light (EM)
transportation is recognized to function as the above data
demonstrates."

[Paul.B.Andersen]

Post by LaurenceClarkCrossen
"Light Speed and Special Relativity"
António Saraiva – 2009-09-13
https://www.gsjournal.net/Science-Journals/Research%20Papers-
Relativity%20Theory/Download/2812

In the following are the statements in quotation marks
quotations from the the paper above:

"The given facts in this analysis are:"

"The light from Jupiter takes 1003 seconds to cross from
the near point of Earth's orbit to the far point at the speed
of 300,000 km/sec, (c) in relation to Jupiter."

My comment:
The light from Jupiter will cross Earth's orbit twice.
The light will use the time 2AU/c = 998 seconds.

"It is known that Earth takes about 200 days to make this same trip.
The Earth's average retreating speed in relation to Jupiter is
17.361 km/sec."

My comment:
The orbital speed of Jupiter is 13.1 km/s, and the orbital
speed of the Earth is 29.8 km/s.
Since the orbits are two concentric circles the retreating
speed varies from 0, to 29.8 km/s, back to 0, to -29.8 km/s,
and back to 0.
The average is ~0. Which is utterly irrelevant.

"When two things race between two points at the same time at differing
speeds,... they have a relative speed that is equal to the difference
between the highest and lowest speed. Therefore the average relative
speed is approximately 300,000 minus 17.361 km/sec."

This is an awkward way of stating:
If the speed of light relative to Jupiter is c, then the speed of light
will vary between c + 29.8 km/s and c - 29.8 km/s relative to the Earth.

Let us express it correctly:

In the inertial rest frame of Jupiter the speed of light is c,
and the speed of the Earth is -29.8 km/s.
The speed difference is c-29.8 km/s. (sometimes called "closing speed")

In the inertial rest frame of the Earth the speed of light is c,
and the speed of Jupiter is -29.8 km/s.
The speed difference is c-29.8 km/s.

That the speed of light is invariant means that it is c in all
inertial frames of reference.

If you express it as "the speed of light is c relative to all
objects", it may be right, but is prone to be misunderstood,
as Saraiva did.

But what Savira really did, was to claim: The speed of light
is not invariant, because the speed of light isn't invariant.

[LaurenceClarkCrossen]

Post by Paul.B.Andersen

Post by LaurenceClarkCrossen
"Light Speed and Special Relativity"
António Saraiva – 2009-09-13
https://www.gsjournal.net/Science-Journals/Research%20Papers-
Relativity%20Theory/Download/2812

In the following are the statements in quotation marks
"The given facts in this analysis are:"
"The light from Jupiter takes 1003 seconds to cross from
the near point of Earth's orbit to the far point at the speed
of 300,000 km/sec, (c) in relation to Jupiter."
The light from Jupiter will cross Earth's orbit twice.
The light will use the time 2AU/c = 998 seconds.
"It is known that Earth takes about 200 days to make this same trip.
The Earth's average retreating speed in relation to Jupiter is
17.361 km/sec."
The orbital speed of Jupiter is 13.1 km/s, and the orbital
speed of the Earth is 29.8 km/s.
Since the orbits are two concentric circles the retreating
speed varies from 0, to 29.8 km/s, back to 0, to -29.8 km/s,
and back to 0.
The average is ~0. Which is utterly irrelevant.
"When two things race between two points at the same time at differing
speeds,... they have a relative speed that is equal to the difference
between the highest and lowest speed. Therefore the average relative
speed is approximately 300,000 minus 17.361 km/sec."
If the speed of light relative to Jupiter is c, then the speed of light
will vary between c + 29.8 km/s and c - 29.8 km/s relative to the Earth.
In the inertial rest frame of Jupiter the speed of light is c,
and the speed of the Earth is -29.8 km/s.
The speed difference is c-29.8 km/s. (sometimes called "closing speed")
In the inertial rest frame of the Earth the speed of light is c,
and the speed of Jupiter is -29.8 km/s.
The speed difference is c-29.8 km/s.
That the speed of light is invariant means that it is c in all
inertial frames of reference.
If you express it as "the speed of light is c relative to all
objects", it may be right, but is prone to be misunderstood,
as Saraiva did.
But what Savira really did, was to claim: The speed of light
is not invariant, because the speed of light isn't invariant.

Saraiva showed by the two graphs that the time between the eclipses of
Io varies in trends. When Earth and Jupiter move apart, the eclipses are
increasingly further apart in time, and vice versa. This would require
that the relative speeds of Jupiter and Earth affect the relative speed
of light.

[Mikko]

Post by LaurenceClarkCrossen

Post by Paul.B.Andersen

Post by LaurenceClarkCrossen
"Light Speed and Special Relativity"
António Saraiva – 2009-09-13
https://www.gsjournal.net/Science-Journals/Research%20Papers-
Relativity%20Theory/Download/2812

In the following are the statements in quotation marks
"The given facts in this analysis are:"
"The light from Jupiter takes 1003 seconds to cross from
the near point of Earth's orbit to the far point at the speed
of 300,000 km/sec, (c) in relation to Jupiter."
The light from Jupiter will cross Earth's orbit twice.
The light will use the time 2AU/c = 998 seconds.
"It is known that Earth takes about 200 days to make this same trip.
The Earth's average retreating speed in relation to Jupiter is
17.361 km/sec."
The orbital speed of Jupiter is 13.1 km/s, and the orbital
speed of the Earth is 29.8 km/s.
Since the orbits are two concentric circles the retreating
speed varies from 0, to 29.8 km/s, back to 0, to -29.8 km/s,
and back to 0.
The average is ~0. Which is utterly irrelevant.
"When two things race between two points at the same time at differing
speeds,... they have a relative speed that is equal to the difference
between the highest and lowest speed. Therefore the average relative
speed is approximately 300,000 minus 17.361 km/sec."
If the speed of light relative to Jupiter is c, then the speed of light
will vary between c + 29.8 km/s and c - 29.8 km/s relative to the Earth.
In the inertial rest frame of Jupiter the speed of light is c,
and the speed of the Earth is -29.8 km/s.
The speed difference is c-29.8 km/s. (sometimes called "closing speed")
In the inertial rest frame of the Earth the speed of light is c,
and the speed of Jupiter is -29.8 km/s.
The speed difference is c-29.8 km/s.
That the speed of light is invariant means that it is c in all
inertial frames of reference.
If you express it as "the speed of light is c relative to all
objects", it may be right, but is prone to be misunderstood,
as Saraiva did.
But what Savira really did, was to claim: The speed of light
is not invariant, because the speed of light isn't invariant.

Saraiva showed by the two graphs that the time between the eclipses of
Io varies in trends. When Earth and Jupiter move apart, the eclipses are
increasingly further apart in time, and vice versa. This would require
that the relative speeds of Jupiter and Earth affect the relative speed
of light.

No, it does not. It is sufficient that light travels at some finite speed.
You need more numbers if you want to show that that speed is or is not
always the same.

[Paul.B.Andersen]

Post by LaurenceClarkCrossen

Post by LaurenceClarkCrossen
"Light Speed and Special Relativity"
António Saraiva – 2009-09-13
https://www.gsjournal.net/Science-Journals/Research%20Papers-
Relativity%20Theory/Download/2812

Saraiva showed by the two graphs that the time between the eclipses of
Io varies in trends. When Earth and Jupiter move apart, the eclipses are
increasingly further apart in time, and vice versa. This would require
that the relative speeds of Jupiter and Earth affect the relative speed
of light.

The two graphs are real measurements, not made by Saraiva.

If you don't understand that the visually measured
(through a telescope) orbital frequency of Io will increase
when Jupiter is retreating from Earth _because_ the speed of
light relative to the Earth is constant, then you are as stupid
as Saraiva.

I won't bother to explain.

Look up Rõmer's experiment.