Initial Verification
A number of experimenters initially claimed to have identified the effect using astronomical measurements, and the effect was eventually considered to have been finally identified in the spectral lines of the star Sirius B by W.S. Adams in 1925. However, measurements of the effect before the 1960s have been critiqued by (e.g., by C.M. Will), and the effect is now considered to have been definitively verified by the experiments of Pound, Rebka and Snider between 1959 and 1965.
The Pound–Rebka experiment of 1959 measured the gravitational redshift in spectral lines using a terrestrial 57Fe gamma source. This was documented by scientists of the Lyman Laboratory of Physics at Harvard University. A commonly cited experimental verification is the Pound–Snider experiment of 1965.
More information can be seen at Tests of general relativity.
Read more about this topic: Gravitational Redshift
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