How easy is it to create a natural moon?
The current speculation is that our moon was formed in a collision between another space object (probably the size of Mars) and the Earth throwing matter up and into orbit around the Earth.
It was pointed out (in http://www.thenakedscientists.com/forum/index.php?topic=1333.msg11750#msg11750) that matter ejected from the surface of the planet will generally either fall back to that planet, or keep going for ever, but is not easy to get into orbit.
The other way of obtaining a moon is to capture an existing space object into orbit around the planet.
We (the Earth) have one moon, that was created very early on in the history of the Earth. As far as I know, we have neither thrown up, nor captured, any other satellites (aside from man made ones) in all of the history of this planet.
Clearly, creating natural moons is a rare event – how likely is it that we will ever get another natural moon (however small) at some time in the future? Is it at all feasible, whether probable or improbable or impossible?