Another thought confuses the issue, but I think it is relevant to the discussion.

Some time ago, if I remember correctly, when we were discussing the speed of light through water, and other media, we established that light travels at “c” through any medium, and that the apparent slowing results from the absorption and re-emission of the photons by atoms in the medium.

If this is the case, why are astronomers able to see the emission/absorption spectra of distant stars? Why are these spectra not converted into the emission spectra of the atoms in the lenses of their telescopes?

There never was nothing.