Other Solar Systems (cont)
Radial velocity searches have only found planets about ~5% of stars.
They would not have found our solar system.
Jupiter's orbital period is too long.
Copernican Cosmological Principle:
we are not at a special place.
at a special place.
we have no idea what a typical solar system looks like!
Build solar systems on the computer and try to find out!
So, how do planets form?
Disk of gas and dust forms.
Gas evaporates before all the planets form.
1-10km objects form by two-body accretion.
Local accretion (good analytic models).
Global accretion (no good analytic models).
Inner solar system is warm
Outer solar system is cold
Ice giants and cores of gas giants.
If objects get large enough (
) before gas disk goes away