"Jim Lux" napisal w wiadomosci
...
Brian Howie wrote:

" It was known that different frequencies travel with different speeds
on a
long cable".

Is the same in air and space?

Yes in air , and no in space.

B

Depends what you mean by "space".. perfect vacuum, sure..

But what's between the planets in the Solar System isn't a perfect vacuum,
and so, it shows dispersion due to the presence of small amounts of
ionization.

Granted, it's generally a better vacuum than you are likely to achieve on
Earth by mechanical means.

Speed of waves in a dispersive medium is temperature dependent.
In the Solar System the temperatures are decreasing with the distance from
the Sun.

You have send us: http://ipnpr.jpl.nasa.gov/progress_report/42-65/65I.PDF

It seems to me that the no answer for Maxwell's question:
"Incidentally, Maxwell once suggested that Roemer's method could be used to
test for the isotropy of light speed, i.e., to test whether the speed of
light is the same in all directions. Roemer's method can be regarded as a
means of measuring the speed of light in the direction from Jupiter to the
Earth. Jupiter has an orbital period of about 12 years, so if we use
Roemer's method to evaluate the speed of light several times over a 12 year
period, we will be evaluating the speed in all possible directions (in the
plane of the ecliptic). "

Do you know the answer?
S*