Measured altitude profiles of atomic oxygen, 557.7-nm emissions, and Herzberg I emission between 80 and 120 km were used to test the proposed mechanisms leading to these emissions. As generally assumed, the O2(A3Sm+) that emits the Herzberg I bands is excited by three-body recombination of atomic oxygen. The quenching of this state is by N2 or O2; for N2 the lifetime times the rate is 2.75¿10-13 cm3; other quenchers are insignificant. We find the atomic oxygen O(1S) emitting the green line is excited by the Barth mechanism.