Also as the universe ages the is more and more water in space as time goes on. If light slows down in water does this affect redshift.
It is easily overwhelmed by Earth's air water vapour, which affects the red end of the spectrum very badly. The KH jump looks reliable, so the redshift is OK, but the rest is rubbish. Once the redshift is established, the software just puts labels where it knows the peaks must be, according to the redshift.
Galaxy Color and Redshift Chart » Talk - Zooniverse
Bill, that explanation seems to be counter to the tenants of quantum mechanics, in that an electron in any particular atom is confined to very specific energy levels (orbitals) and cannot absorb just any passing photon to go to a higher energy level that is specific to the photon energy plus the electrons previous quantum energy level. And, there is also an issue with conservation of momentum unless the electron happens to release the photon along exactly the same path as it absorbed it from.In substances, such as air and water, with refractive indices larger than 1.000 the light is delayed by each atom it passes by energizing an electron to a higher orbital, pausing for a moment, and then emerging to continue on at the speed of light to the next atom, where it pauses again. During the period of time it is travelling between atoms it is going at c.
"Somehow"???Yes, absorption and reemission is definitely there. Scattering preserves the momentum vector of the photon somehow.
Scattering does include scattering forward. For Mie Scattering, forward scattering dominates the distribution. Graph here"Somehow"???
Scattering, by definition, means that the direction of the photons is changed.
To conserve momentum, something else must move away from the original path direction of the light after interacting with the photon. See https://www.coursehero.com/study-guides/physics/29-4-photon-momentum/ .
What Bill is suggesting for electrons absorbing and re-emitting light in the exact same direction at the exact same wavelength is not "scattering".