 The hydrogen emission lines at 656.3 nm (the strong H-alpha line) and at 486.1 nm (H-beta) are characteristic for lightnings.Rydberg atoms, generated by low-frequency lightnings, emit at red to orange color and can give the lightning a yellowish to greenish tint.Generally, the radiant species present in atmospheric plasma are N2, N2+, O2, NO (in dry air) and OH (in humid air).