A detailed comparison and assessment of the accuracy of semi-empirical atmospheric density models (JR-71, MSIS-86/90, TD-88) were carried out by analyzing the orbital decay of nine spherical satellites in the 150–1500 km altitude range. The orbital decay data used were distributed over a full solar activity cycle (1987–1999). The drag coefficients which were estimated by fitting the observed semimajor axis evolution with a high accuracy orbit propagator were compared with those computed by theoretical analysis.
While MSIS-86/90 proved to be the best model to compute the air density below 400 km, in low solar activity conditions, JR-71 was more accurate at greater altitudes and/or solar fluxes. TD-88, defined below 700 km, was quite accurate (10%) only during periods of moderate solar activity. Between 350 and 800 km, the average accuracy of JR-71 and MSIS-86/90 was generally better than 15% and, sometimes, even better than 10%. However, at 1500 km and during low solar activity conditions, both models underestimated the air density by 60%, while below 350 km, still during low solar activity conditions, they overestimated the air density by 20–25% and 10–20%, respectively.
Comparison and Accuracy Assessment of Semi-Empirical Atmosphere Models through the Orbital Decay of Spherical Satellites
J of Astronaut Sci
The Journal of the Astronautical Sciences ; 49 , 2 ; 255-268
2001-06-01
14 pages
Article (Journal)
Electronic Resource
English
British Library Conference Proceedings | 2000
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