where n₁ = 1.8675(at +20°C and λ=532nm) is the group refraction index of the inner flint glass ball having a radius of R₁=53.52mm, and n₂=1.4986(at +20°C and λ=532nm) is the group refraction index of the outer crown glass layer having an external radius of R₂=85.16mm.

The geometrical path length of the laser light from the incidence point to the ball center is equal to the radius R₂. Thus, the correction value is:

L₀-R₂ = 2R₁n₁ +2R₂n₂ -2R₁n₂ -R= 199.90 + 255.24 – 160.41 - 85.16 = 209.6 mm

Thus to correct the measured one-way laser range to the center of mass of the satellite, 209.6 mm should be SUBTRACTED from that measured one-way range.

The calculated correction value variation caused by the glass refraction indexes temperature dependence is less than 0.1 mm with in a temperature range of ± 35°C (relative to +20°C).