Middle atmosphere models and comparison with shuttle reentry density data

Several middle atmosphere models will be reviewed, including a new set of models produced by Groves in 1985. The latter models are based on rocket and rawinsonde in situ measurements and satellite remote sounding temperature data. The models are compared with measurements made with instruments on board U. S. Shuttles during their reentry. Very useful atmospheric density data have been obtained in the altitude region from 50 to 80 km. The measurements are unique in that they are made by a vehicle travelling almost horizontally through the atmosphere at a velocity of 6 to 7 km/sec. This results in measurements along a path of approximately 8,000 km in a time interval of about 20 minutes. The results show some unique features.