On Apr 3, 5:07 pm, HW@....(Henri Wilson) wrote:
On Tue, 3 Apr 2007 01:23:35 +0100, "OG" wrote:

4 However, we do not see broad spectral lines from cepheid
variables - hence at any one time the light that we are
receiving was all emitted at the same speed relative to us.

You WOULD EXPECT to see broadened lines from huff-puff cepheids
for the above reason.
If they are narrow, then it backs up the BaTh and the theory
that they are really just ordinary stars in orbit..

If you accept 3 and propose 1 to be true, and imply that 2
is a consequenceof 1, then observation 4 is a problem for you.

Thankyou Og for backing up the BaTh and shooting yourself
in the foot.

Actually, Henri, you've just shot YOURSELF in the foot.

Periodic broadening and narrowing of the spectral lines of Cepheids
is a well documented phenomenon. This periodic Doppler broadening
results from three phenomena operating concurrently:

1) Projection effect. The parts of the photosphere pulsating in
our line of sight show greater Doppler shift than the parts of
the photosphere which are pulsating tangentially with respect
to us.
2) Thermal effect. Doppler broadening due to kinetic effects
varies as the Cepheid heats and cools through its cycle.
3) Turbulence effect. Spectral lines show periodic Doppler
broadening as the Cepheid "boils up" and relaxes.

Here is a good reference for you to read.
http://www.obs-hp.fr/www/preprints/pp119/pp119.html

BaTh fails yet again!!!!!

Jerry