A method is described for deriving atmospheric O and H atom density profiles in the mesopause region using ozone &ngr;3 emissions. The 10--12 &mgr;m hot band intensity determines the O+O2+M recombination rate; the nighttime hot band/cold band ratio determines the chemical destruction rate and hence the H atom density. Calibration of the hot band intensity versus O atom density has been accomplished using hot and cold band emissions observed under sunlit conditions. Derived density profiles are presented for the high-latitude SPIRIT 1 and SPIRE rocket experiments and compared with mass spectrometer/incoherent scatter model predictions. ¿American Geophysical Union 1992