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sqljunkey
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How can someone tell the difference between a super massive galaxy's redshift and a galaxy that is accelerating away?
If you detect light you have one parameter: the measured wavelength. Any "redshift" is inferred from other factors, such as that you are observing a shifted hydrogen spectrum. There is, therefore, nothing inherent in the measured wavelength that tells you anything other than the measured wavelength.sqljunkey said:How can someone tell the difference between a super massive galaxy's redshift and a galaxy that is accelerating away?
The redshift of a galaxy is a measure of how much its light has been stretched to longer wavelengths due to the expansion of the universe. Massive galaxies have a higher redshift because they are farther away and therefore have been affected by the expansion of the universe for a longer period of time. Accelerating galaxies, on the other hand, have a higher redshift because they are moving away from us at a faster rate due to the acceleration of the expansion of the universe.
The redshift of a galaxy can be measured using spectroscopy, which involves splitting the light from the galaxy into its component wavelengths and analyzing the patterns of absorption and emission lines. The redshift is then calculated by comparing the observed wavelengths to the known wavelengths of these lines.
The difference in redshifts between massive and accelerating galaxies is primarily due to their different distances from us and their relative velocities. The expansion of the universe causes distant galaxies to have a higher redshift, while the acceleration of the expansion causes galaxies to have a higher redshift if they are moving away from us at a faster rate.
The redshift of a galaxy provides important information about the distance and velocity of the galaxy, which can be used to study the expansion of the universe and the distribution of matter within it. By studying the redshifts of galaxies, scientists can gain a better understanding of the history and evolution of the universe.
Yes, the redshift of a galaxy can change over time. This is due to the continued expansion of the universe and the changing distances and velocities of galaxies. However, the change in redshift is usually very small and can only be detected over long periods of time.