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Is it possible to use redshift of photons from the sun? Say if you know the hydrogen transition line frequency, then measure very precisely the observed frequen
by seiferteric 3y ago
Is it possible to use redshift of photons from the sun? Say if you know the hydrogen transition line frequency, then measure very precisely the observed frequency from solar photons, you could calculate the redshift. I suppose this would rely on knowing the mass of the sun already as well.
- Someone 3y agoI think redshift correlates with relative velocity and expansion of the universe, not with distance. https://en.wikipedia.org/wiki/Redshift https://en.wikipedia.org/wiki/Redshift: “The main causes of electromagnetic redshift in astronomy and cosmology are the relative motions of radiation sources, which give rise to the relativistic Doppler effect, and gravitational potentials, which gravitationally redshift escaping radiation. All sufficiently distant light sources show cosmological redshift corresponding to recession speeds proportional to their distances from Earth, a fact known as Hubble's law that implies the universe is expanding.”
- seiferteric 3y agoI thought so as well but recently discovered: https://en.wikipedia.org/wiki/Gravitational_redshift https://en.wikipedia.org/wiki/Gravitational_redshift "gravitational redshift (known as Einstein shift in older literature)[1][2] is the phenomenon that electromagnetic waves or photons travelling out of a gravitational well (seem to) lose energy. This loss of energy corresponds to a decrease in the wave frequency and increase in the wavelength, known more generally as a redshift. "