Abstract:

 The concepts of motion，force，momentum，energy of objects are basic and very important in the

teaching of College Physics. In Newton mechanics，the future motion state can be predicted for an orderly system if

the initial condition is given. Newton mechanics makes a great success in astronomy. In this paper，by using universal

law of gravity，the theorem of momentum and combining the VPython software，the motion of the celestial body

　　is studied. The special examples discussed in detail are the satellite and the moon orbiting with the earth，the Mars

　　rotating about the sun，and the satellite moving around the binary star，etc. The path and the moving process could

　　be visualized intuitively in real time. The teaching experience indicated that simulating and visualizing the orbital

　　motion of celestial body based on VPython is a very powerful method to improve student's ability of understanding

　　and applying Newton's law of motion and theorem of momentum.

Key words: VPython, visualization, theorem of momentum, orbital motion of celestial body