Accession Number:

ADA067237

Title:

Determination and Geophysical Interpretation of the Orbit of China 2 Rocket (1971-18B).

Descriptive Note:

Technical rept.,

Corporate Author:

ROYAL AIRCRAFT ESTABLISHMENT FARNBOROUGH (ENGLAND)

Personal Author(s):

• Hiller,H.

Report Date:

1978-08-01

Pagination or Media Count:

50.0

Abstract:

The orbit of China 2 rocket, 1971-18B, has been determined at 114 epochs throughout its 5-year life, using the RAE orbit refinement program PROP 6, with more than 7000 radar and optical observations from 83 stations. The rocket passed slowly enough through the resonances 141, 292, 151 and 312 to allow lumped geopotential harmonic coefficients to be calculated for each resonance, by least-squares fittings of theoretical curves to the perturbation-free values of inclination and eccentricity. The rotation rate of the upper atmosphere, at heights near 300 km, was estimated from the decrease in orbital inclination, and values of 1.15, 1.05, 1.10 and 1.05 revday were obtained between April 1971 and January 1976. From the variation in perigee height, 25 values of density scale height were calculated, from April 1971 to decay. A further 1400 observations, made during the final 15 days before decay, were used to determine 15 daily orbits. Analysis of these orbits reveals a very strong west-to-east wind, of 240 or - 40 ms, at a mean height of 195 km under winter evening conditions. Author

Descriptors:

• *SATELLITE TRACKING SYSTEMS
• EARTH ORBITS
• HARMONICS
• RESONANCE
• UPPER ATMOSPHERE
• SCIENTIFIC SATELLITES
• APOGEE
• PERIGEE
• UNITED KINGDOM

Subject Categories:

• Unmanned Spacecraft
• Spacecraft Trajectories and Reentry

Distribution Statement:

APPROVED FOR PUBLIC RELEASE