Question is 8 planets (no need info on the number of moons) only.
Question is creating a model (I assume a physical model).
The relevant information to the question (from Encylopedia reference book) :-
All scales using Earth = 1 as the relative scaling
Planet.........Mass.......Diameter...........Volume ........ Distance from Sun
=======================================================
Mercury........ 0.06 ...... 0.383 .......... 0.056 .............. 0.39
Venus.......... 0.82 ...... 0.949 .......... 0.854 .............. 0.72
Earth.......... 1.00 ...... 1.000 .......... 1.000 .............. 1.00
Mars........... 0.11 ...... 0.533 .......... 0.151 .............. 1.52
Jupiter........ 318 ....... 11.209 ......... 1408.377 ............ 5.20
Saturn......... 95.2 ...... 9.449 .......... 843.736 ............ 9.54
Uranus......... 14.5 ...... 4.007 .......... 64.354 ............. 19.19
Neptune........ 17.2 ...... 3.883 .......... 58.548 ............. 30.1
Reference : Space Encyclopedia (never direct copy from websites)
Apart from using the above figures, you need to make the Sun in the middle surrounded by the 8 Planets. However, you cannot use the absolute scale of Sun because the Sun is ultra (very very very) big [everyone knows]. Therefore, making a Sun big enough is acceptable.
One point to note, you need to color them well to make it looks as real as possible. Check out the NASA 美國太空總署 website (
http://solarsystem.nasa.gov/planets/index.cfm) for details. One more point, remember to make the 'ring' for Saturn.
參考: NASA 美國太空總署, Space Encyclopedia by Heather Couper & Nigel Henbest 1999