Planets: the subjects of moral rights???

The same issue of AEI mentioned in the previous post contains a little blurb on Australian Ph.D. candidate Paul York, who in the October/November issue of the Philosophy Now magazine argues against terraforming (remaking another world -- like Mars, for instance -- to fit human needs) because such a planet ought to have moral rights. He apparently believes that in such a situation, the interests of the planet would have to be weighed against the interests of the humanity.

I'm serious.