Buy Yourself a Moon

I heard of several companies that offer all kind of interesting stuff
such as propery on the Moon, on Mars or names of stars. I wonder
whether these companies has the right to sell such things? Our planets
and stars belong to the whole humanity, and their names should and
fates should be decided by special comitties.
I assume that these gift certificates are void, no respectable body
will ever recognize you as the owner of a planet, or a name of a star.

So what do you think about that?