"But who has the final say as to whether the planet will be colonized?"

At first, only the planets similar to Earth can be colonized.

Most people believe that all the planets were colonized by a common human stock, a few million years ago.

Life must have been simpler before the planets were colonized!

If the population is low to begin with, the planet will most likely become uninhabited and free to be colonized.

This planet has been colonized for three hundred years.

Other planets had been colonized as well, most with permission from the Hegemony, but some without it.

To some planet colonized but very thinly settled if not.

Suitable planets within practical range were colonized and a federation established.

If a planet is colonized, it is removed from the sector.