Am just wondering what the currently accepted measurement standard is for the Lyman series spectral lines. At NIST I find the following set of measured wavelengths (nano meters): 91.9342 92.0947 92.3148 92.6249 93.0751 93.7814 94.9742 97.2517 102.5728 121.56701 At http://www.trinitas.ru/rus/doc/0016/001b/00161313.htm I find another set of measured wavelengths: 91.93514 92.09631 92.31504 92.62257 93.07483 93.78035 94.97431 97.25368 102.57223 121.56701 1. Which set of data is the currently accepted measurement standard ? 2. Also the Russian site is using the value 1.0967878E+07 for the Rydberg constant and I would like to know where that comes from since it is neither the same as Codata 1.0973731569E+07 nor reduced mass corrected value of 1.0967758341E+07. The value they are using seems to calculate the second set of values to a very high level of precision without recourse to anything other than the standard Rydberg formula. 3. Finally are the measured values from sun spectra or from some or other terrestrial light source ? Because at some level of accuracy one would presumably have to start accounting for gravitational redshift of solar spectra.