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Zhang, Jing-Chang

Publications and source records attributed to Zhang, Jing-Chang.

NASA/JSC orbital debris models

The orbital debris models developed within the framework of the NASA Johnson Space Center's (JSC's) orbital debris program, are categorized as environment definition and risk assessment models. The EVOLVE, CHAIN and the orbital debris engineering model 1996 (ORDEM96) computer programs determine the past, present and future orbital particulate environment, while the BUMPER and debris assessment software (DAS) computer programs provide a means for evaluating the risks of specific space missions. These models are presented. To support these models and to conduct specialized analyses, NASA/JSC employs a range of auxiliary models, including explosion and collision satellite breakup models, hypervelocity impact ballistic limit models, orbit propagation and decay models, space traffic models and solid rocket motor effluent models.

Johnson, Nicholas↗

Modeling fluxes resulting from new or Molniya-class objects

The behavior of objects in Molniya-type orbits and debris objects produced in new breakups are considered. As the majority of breakups in highly eccentric orbits occur in Molniya-type orbits, it is of interest whether, and how, debris objects can interfere with the geosynchronous earth orbit and low earth orbit regions. The behavior of such objects are determined principally by the initial argument of perigee and the initial inclination. The closer the initial orbit's argument of perigee is to 270 deg, and the inclination is to the critical inclination of 63.4 deg, the longer the perigee appears to be locked in the southern hemisphere. The impact on the low earth orbit region is illustrated as the interference of debris objects with the International Space Station's orbit. The possible interactions of Molniya-type debris and with the geostationary ring is demonstrated.

Siebold, Karl H.↗