In the beginning of the 17th century, Johannes Kepler (1571 -1630), using observations made by Tycho Brahe (1546-1601), waged his war on Mars. He won his war with the discovery of the three laws of planetary motion, bringing about a revolutionary change in astronomy, harbingering celestial mechanics of Isaac Newton.

More than five centuries earlier, in the 11th century China, in the Northern Song dynasty, there was a polymath elite official Shen Kua (1031-1095) who, realizing the serious discrepancies in the prediction of planetary movements, proposed a project to tackle the problem. Shen Kua’s project, however, ended in abortion. He could not achieve anything remarkable on the computation of planetary motion. The eleven century Northern Song China, so to speak, did not produce a Kepler.

I deliberately ask this unhistorical question to raise to awareness the fact that, in terms of accuracy of the calculation of planetary motion, China in the eleventh century had already reached the similar level of the West in the sixteenth century. The Chinese had also realized problems in the prediction of planetary motion, and set to work on it. This failure to make any recognizable progress as similar to that of Kepler is something worth to be studied. We will find out many factors, technical and social, that had inhibited the development of planetary astronomy in China, thus gain fuller insight into ancient Chinese astronomy.