In
general, LGS don’t help at all with the problem of precisely measuring
the magnitudes of astronomical sources. Moreover, the problem of
precisely measuring magnitudes — unlike the problem of
eliminating atmospheric distortion — is unfortunately not“simply solved” by moving one’s telescope above the Earth’s atmosphere
into space [12]. However, by exciting certain alternative resonances
(i.e., instead of the D2 resonance) of the
upper-atmospheric sodium atoms, one can create a mandatory “cascade”
of sodium de-excitations, that will then create a two-color artificial
star with a precisely 1:1 ratio of yellow (589 nm) to near-infrared (820
nm) photons that are produced in the upper atmosphere. Since the
precision of that 1:1 photon production ratio will be known to better
than a part in 104 (i.e., better than 0.01%), such a
“laser photometric ratio star” (LPRS) would allow the calibration of
astronomical magnitudes