But Also Consider Exoplanetary Systems

Some exoplanets orbit pulsars.

Some exoplanet systems are non-coplanar (eccentric orbits).

Some exoplanets orbit in the opposite direction with regard to its star’s rotation (retrograde orbits).

Then there are “hot” Jupiters that no one expected to find.

These systems are exceptions to the rule, but theory must be able to explain them too.