Accession Number:

ADA052334

Title:

The Altitude Dependence of the Local Time Variation of Thermospheric Density.

Descriptive Note:

Interim rept.,

Corporate Author:

AEROSPACE CORP EL SEGUNDO CALIF IVAN A GETTING LABS

Report Date:

1978-03-10

Pagination or Media Count:

20.0

Abstract:

Analysis of density measurements from the AE-E satellite have demonstrated that the local time variation in the thermosphere at low latitudes 20 changes from predominantly diurnal at thigh altitudes about 300 km to predominantly semidiurnal at low altitudes about 140 km. This behavior is significant because it both affects the accuracy of density predictions at low satellite altitudes and confirms that the mesospheric semidiurnal tide is important to the dynamics of the lower thermosphere. Comparison of the results with the local time dependence found in the thermospheric model of Jacchia 1971 and the MSIS model of Hedin et al. 1977 a and b indicate that only the latter correctly models the transition to dominantly semidiurnal behavior at lower thermospheric altitudes near the equator. Author

Subject Categories:

  • Atmospheric Physics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE