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The global lunar image of the first phase of Chinese Lunar Exploration Program is the first image that covered all over the surface of the Moon. It will serve as a critical foundation for succeeding exploration and scientific research. In this paper, the acquisition, characteristics, and data quality of Chang'E-1 CCD image data are described in detail. Also described are the methodology and procedure of data processing. According to rule of planetary cartography, the image data have been processed, geometrically corrected, and then mosaicked and merged in a scale of 1:2.5 million. The results of data processing and charting show that the image data of Chang'E-1 CCD and their geometric precision meet the demand of charting a map in the scale of 1:2.5 million. The relative geometric positioning precision of the global image is better than 240 m, and the absolute geometric positioning precision is slightly better than that of the ULCN2005 and Clementine lunar basemap (V2.0). The plane positioning precision is approximately 100-1500 m. This global image proves to be the best global image of the Moon so far in terms of space coverage, image quality, and positioning precision.Chang'E-1, lunar CCD data processing, lunar image position, lunar global image Citation:Li C L, Liu J J, Ren X, et al. The global image of the Moon obtained by the Chang'E-1: Data processing and lunar cartography.

The Laser AltiMeter (LAM), as one of the main payloads of Chang'E-1 probe, is used to measure the topography of the lunar surface. It performed the first measurement at 02:22 on November 28th, 2007. Up to December 4th 2008, the total number of measurements was approximately 9.12 million, covering the whole surface of the Moon. Using the LAM data, we constructed a global lunar Digtal Elevation Model (DEM) with 3 km spatial resolution. The model shows pronounced morphological characteristics, legible and vivid details of the lunar surface. The plane positioning accuracy of the DEM is 445 m (1σ), and the vertical accuracy is 60 m (1σ). From this DEM model, we measured the full range of the altitude difference on the lunar surface, which is about 19.807 km. The highest point is 10.629 km high, on a peak between crater Korolev and crater Dirichlet-Jackson at (158.656°W, 5.441°N) and the lowest point is −9.178 km in height, inside crater Antoniadi (172.413°W, 70.368°S) in the South Pole-Aitken Basin. By comparison, the DEM model of Chang'E-1 is better than the USA ULCN2005 in accuracy and resolution and is probably identical to the DEM of Japan SELENE, but the DEM of Chang'E-1 reveals a new lowest point, clearly lower than that of SELENE.Chang'E-1, laser altimetry, lunar DEM, topographic tops of the Moon Citation:Li C L, Ren X, Liu J J, et al. Laser altimetry data of Chang'E-1 and the global lunar DEM model.

China’s first Mars exploration mission (HuoXing-1) has been named as ‘Tianwen-1’ meaning Heaven Inquiry. Tianwen-1 was launched on July 23, 2020. In this paper, the scientific objectives of earlier and current Mars exploration missions worldwide are reviewed, and the scientific objectives, payloads and preliminary scientific investigation plan of China’s first Mars exploration mission are introduced, and expected scientific achievements are analyzed.

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Observations of ten Compact Symmetric Objects (CSO) candidates have been made with the Very Long Baseline Array at 8.4 GHz in 2005 and with a combined Chinese and European VLBI array at 8.4 GHz in 2009. The 2009 observations incorporate for the first time the two new Chinese telescopes at Miyun and Kunming for international astrophysical observations. The observational data, in combination with archival VLBA data from previous epochs, have been used to derive the proper motions of the VLBI components. Because of the long time baseline of ∼16 years of the VLBI data sets, the expansion velocities of the hot spots can be measured at an accuracy as high as ∼1.3 µas yr −1 . Six of the ten sources are identified as CSOs with a typical double or triple morphology on the basis of both spectral index maps and their mirror-symmetry of proper motions of the terminal hot spots. The compact double source J1324+4048 is also identified as a CSO candidate. Among the three remaining sources, J1756+5748 and J2312+3847 are identified as core-jet sources with proper motions of their jet components relating to systemic source expansion. The third source J0017+5312

Measurement results of some properties of the Miyun 50 m radio telescope (MRT50) of the National Astronomical Observatories, such as pointing calibration, antenna beams, system noise temperature, gain and gain variations with elevation are introduced. By using a new de-convolution technique developed by our group, the broadening effect on measured beams caused by the width of an extended radio source has been removed so that we obtained higher accuracy on the measurements of MRT50 beams.