ATMOSPHERIC STRUCTURE OF MARS AT 120-220-km ALTITUDES.

Altitude dependences were found for left bracket CO//2 right bracket and left bracket CO//2** plus right bracket . The two CO//2 profiles are in good agreement at 130 km, but at greater altitudes there is increasing disagreement, and at 200-220 km the left bracket CO//2 right bracket is only one third of that which corresponds to the model. The temperature profile has a gradient of similar 2 deg/km at 150-200 km with T equals 370 degree K at 220 km. For its explanation it is necessary to include the effect of gravitational and acoustic waves as an essential source of atmospheric warming at these altitudes: their energy flux must be similar 4. 10** minus **2 erg/cm**2. sec at an altitude of 180 km. The ratio of left bracket CO//2 right bracket /n//e equals 0. 15-0. 2 and corresponds to left bracket O right bracket / left bracket CO//2 right bracket equals 3% at 135 km. A model is constructed for the atmosphere and ionosphere at altitudes of 120-220 km.