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In this paper the precision of the VLBI tracking delays and the positioning reduction results during the real-time stage of the Chang'E-2 project is statistically analyzed, the application of the positioning reduction to the real-time monitoring of the pivotal arcs of the Chang'E-2 satellite is discussed, the related technical specifications of the experiment of X-band monitoring and control system are estimated and evaluated via the positioning reduction method. Useful methodology and software are prepared as well as practical experience in engineering and technology is accumulated for the follow-on lunar exploration projects of China.

From March 31 to April 4 and from April 13 to 17, the 1667 MHz OH line of comet Halley was observed in Shaanxi province of China with the 25B radio telescope of Shanghai Observatory and a 128-channel autocorrelation spectrometer of Peking University. The bandwidth of the spectrometer was 625 KHz and the resolution was 4.92 KHz (0.89 km/s). The receiver was frequency-switched with a frequency shift of 197 KHz. In order to improve the signal-to-noise ratio, we accumulated the 1667 MHz profiles of April 13 to 17. According to the synthetic profile, we can summarize the results as follows: 1. (1) The intensity of the absorbed OH flux was calibrated by means of measurements of the 1667 MHz OH line of W12. The observed mean OH flux of 4 days is −2.4 Jy. 2. (2) The measured OH expansion velocity VOh = 0.92 km/s, when the heliocentric distance rh = 1.39 AU. 3. (3) The profile asymmetry may be characterized by the first order moment Δv= 0.20 km/s. 4. (4) The mean OH parent production rate Qp = 1.7 × 1029 mol/s, assuming Hasser's model with the parameters defined in Despois et al.