How Did Planets Enter Their Orbits?

[ajassat]

This is something I thought about while drifting off to bed last night.

Immediately after the period between the big bang and the formation of planets, how did these newly created planets enter their respective orbits.

I'm assuming the planets had different masses and that this was a major factor in deciding the location of the orbit in relation to the sun and other planets

Can somebody shed more light on this?

 

[DaveC426913]

No. The dust and gas that settled out of the BB coalesced into spinning, contracting disks. These disks shrank under gravity, causing their rotation to speed up. Eventually the centre formed a star with a disk. The disk started clumping and these clumps became planets. The planets swept up the remaining dust and gas until there was just a star and a bunch of planets in various orbits.

 

[D H]

In a nutshell, gravity.

For a longer explanation, Google is your friend. Some key phrases to help your search: Planet formation, nebular hypothesis, protoplanetary disk.

This is a good article: http://www.scientificamerican.com/article.cfm?id=the-genesis-of-planets.

 

[ajassat]

Thank you for pointing me in the right direction.