Example of observed NH₃ (1, 1) hyperfine structure lines, the outer satellite lines are denoted by O1 and O2, the inner hyperfine lines by I1 and I2, and the main line by H. The NH₃ hyperfine structure fit assuming LTE conditions is overlaid in green, which displays equal intensities of O1 and O2 as well as of I1 and I2. The outer satellite lines of the observed spectrum deviate from this prediction.