describe the spacing of the planets in the solar system?

Answer 1

The spaces are big.

Could you be a bit more specific? Do you need exact distances? Take a look at wikpedia: http://en.wikipedia.org/wiki/Planets

Answer 2

There are lots of tables and lists out there to find the actual distances.

However, when you only need an approximation, you can use Titius-Bode's Law:
M 4
V 4+3
E 4+3*2
M 4+3*(2^2)
? 4+3*(2^3)
J 4+3*(2^4)
S 4+3*(2^5)
and so on

Then divide by ten to find relative distances (in astronomical units). For example, 4 + 3*(2^5)= 4 + 3*32 = 4 + 96 = 100
Divided by ten = 10 (approximate distance to Saturn)

Compare with actual values:
0.4 (Mercury; real mean distance is 0.387)
0.7 (Venus; real = 0.723)
1.0 (Earth; by definition, at 1.0 A.U.)
1.6 (Mars; 1.524)
2.8 (no planet)
5.2 (Jupiter; 5.202)
10 (Saturn; 9.56)
19.6 (Uranus; 19.19)
38.8 (Neptune is only at 30.1)

This was published in 1768, before the discovery of Uranus.
Uranus was discovered in 1781 and gave condidence that the list had some merit. The gap at 2.8 caused many astronomers to search for the missing planet. In 1801, found Ceres, the first of millions of asteroids, most of which orbit in the main asteroid belt located at roughly the correct distance to fit the list.

However Neptune did not fit. And attempts to find a physical reason why the list works have... not worked. So the list is considered more a mathematical fluke than anything else.

Still, it is useful when you try to remember approximate distances.

Answer 3

This is a very complex subject you will need to do some research yourself.

The planets and their speed and position all obey Kepler's Laws of planetary motion which basically states that all planets sweep the same elliptical area in the same time as they rotate around the Sun. Here is a link for you and if you search under Kepler's Law, you will find dozens more.

http://home.cvc.org/science/kepler.htm

Jules, Australia.

Answer 4

Mercury, Venus and Earth are (relatively speaking) quite close to each other.

Jupiter, Saturn, Uranus and Neptune, however have much, much bigger distances between then. When Pluto was a planet, it was even more ridiculously far away.