Source: clep.org.cn
10-20-2007 10:44
Chief Commander for Chang'e Program, Luan Enjie
The U.S. is the leader in deep space exploration. Apart from Pluto for which no touching exploration has been made, all the planets in the solar system have been preliminarily probed by mankind. Generally speaking, lunar exploration can be divided into three major stages, i.e. automatic exploring, human landing and, finally, staying (living). The U.S. has succeeded in the first two stages, and its current lunar program is primarily focused on the third stage, or the “staying (living)” stage, i.e. developing and launching automatic or man-tended lunar staying devices, or creating conditions for crews to live, to work and to conduct experiments, so as to perform scientific activities on the lunar surface.
Based on the current conditions, we think that a realistic approach should be taken in selecting our goals. The guiding principle should be to focus on “automatic exploring” at first, in doing so to gradually accumulate knowledge and experience step by step, and to timely improve our launch vehicle capacity to meet the requirements of future deep space exploration efforts. By this way we have formed China’s lunar exploration program that features three milestones, i.e. “orbiting”, “landing” and “returning”.
Orbiting – Chang’e-1, a lunar orbiting spacecraft, will be launched.
Landing – A spacecraft will be launched to deploy a lunar lander for surface exploration in a limited area on the moon.
Returning – On the basis of the lander mission, a lunar sample return mission will be implemented.
Phase 1 of the program, or the Chang’e-1 lunar orbiter project, was initiated in 2004. With key technical problems solved and a prototype model developed, the project moved into flight model production in 2006. If everything goes well, the Chang’e-1 orbiter is expected to be launched in 2007.
The Five Major Systems of the Chang’e-1 Project
Spacecraft Platform: The platform is based on the one used for the DFH-3 communications satellite. Mature technologies and experiences from related satellite missions have been fully inherited and utilized. In terms of technical configuration, Chang’e-1 is actually a new spacecraft. And we have had a stronger sense of this along with the progress of the development work.
Launch Vehicle: The LM-3A launch vehicle, which is primarily designed to launch satellites based on the DFH-3 platform, has been selected to launch Chang’e-1. LM-3A has succeeded in all of its nine flights, seven of which have been made for satellites based on the DFH-3 platform. For the Chang’e-1 mission, the launch vehicle has been adapted in many areas. Particularly, major efforts have been made to improve its reliability, with redundant designs used on a number of critical links.
Launch Site System: Chang’e-1 will be launched at Xichang Satellite Launch Center, a launch site for China’s geosynchronous satellites. The launch center has been modified in many areas to adapt it to the requirements of a lunar mission, especially in safety and reliability.
TT&C System: The TT&C System has been formed based on China’s existing TT&C bases and instrumentation ships for space missions. To improve orbital measurement accuracy and provide redundant means for TT&C, astronomical Very Long Baseline Interferometry (VLBI) will be used for the first time in China to provide right ascension and declination needed for orbital measurement and determination of Chang’e-1.
Ground Application System: The so-called Ground Application System refers to the system responsible for Chang’e-1 downlink data reception, science data processing and study and in-orbit operation of the spacecraft.
Editor:Liu Fang