Explanation of Planet Order

[clocker]

I'll do better next time, promise.

[manker]

Now I'm thinking that the rod was deliberately poor such that my commenting on it entangled my lip in clocker's feisty barb.

[clocker]

Wheels within wheels, manks.

[ktasera]

Actually, since planetary orbits are elliptical, when pluto was a planet it used to switch places (I mean, be closer to the sun) with neptune once in a while.

[clocker]

So, since we decided Pluto isn't a planet it's changed it's orbit in spite?

[Snee]

Anyways, the solar system in fast forward: Cloud of gas, collapsing cloud of gas, gas compressed to rotating accretion disc, accretion disc breaking up into chucks, chunks banging into each other, planetoids, planets, sun in the middle, and in the far future: sun going out, sun swelling up out to mars or so, stuff further out floating off, sun collapsing again dragging the innermost planets in, into a brown dwarf or something.

Gravity working against centrifugal force holds them in place around the sun, I think. Most were part of the disc, so they rotate in the same orbit, pluto (I think it's pluto anyways) rotates differently cos it came from elsewhere and got caught by gravitation, hence it has a slightly different orbit compared to the others, sometimes going inside the orbit of neptune (I think) changing the order now and then.

[SAM]

they placed where they are because of the gravity forces between them that what keep them stable in their orbits

[Squeamous]

I think I read somewhere once that the planets are the composition they are because of their position around the sun. That the elements that compose them tend to congregate at certain distances from the sun inside the spinning disc of matter as they form, so that when scientists look for signs of life in other solar systems they always look for a planet the same distance as Earth from the foreign sun...so it has just the right amount of temperature and the most likely composition. Is this complete bollocks or have I remembered it right?

[Snee]

Dunno what fake sam said, but it's probably fucking stupid or adds nothing useful. Disregard everything he says.

[Snee]

I think I read somewhere once that the planets are the composition they are because of their position around the sun. That the elements that compose them tend to congregate at certain distances from the sun inside the spinning disc of matter as they form, so that when scientists look for signs of life in other solar systems they always look for a planet the same distance as Earth from the foreign sun...so it has just the right amount of temperature and the most likely composition. Is this complete bollocks or have I remembered it right?

Different elements have different composition, so it sounds sensible that they'd be distributed somewhat unevenly, what with the forces pulling on them. The sun is mostly hydrogen and helium (the pressure inside the sun creates a fusion reaction kind of thing turning hydrogen into helium), pretty light stuff.

I suppose we might have just the right mix, and it might be that heavier elements or something are more common further out.

Can't really count on everything laying about all orderly though, element-wise, there are fairly chaotic matters to factor in, like stuff coming from the outside, like asteroids and so forth.