Precise orbit determination of the low altitude spacecraft trmm, GFZ-1, and EP/EUVE using improved drag models

摘要

The launch of the Tropical Rainfall Measurement Mission (TRMM) on November 27, 1997 provided a unique opportunity to improve geopotential models, which laked tracking data from satellites at such low altitude (351 km), and inclination (35.0 degrees). Tracking is provided by NASA's Tracking and Data Relay Satellite System, which provides excellent tracking coverage over the Western Pacific and Mid Atlantic regions. A long standing obstacle to low-altitude orbit determination has been limitations in drag modeling, particularly for large complicated spacecraft such as TRMM. Application of thermospheric wind, free molecular flow, and "box-wing" models, to account for temporal variations in the coefficients of lift and drag, improved the orbit determination for this satellite. these models are also shown to have application to spherical satellites at low altitude, such as the German GeoForschungsZentrum-1 (GFZ-1) geodetic satellite at 350 km and 51.7 degree inclination, and other large spacecraft such as the Explorer Platform/extreme Ultraviolet Explorer (EP/EUVE) at 517 km and 28.5 degrees inclination.