Planets which were once settled by humanity, but are now no longer part of civilized space. Despite the connotations of the word abandoned, these planets may still have human beings living on them. However, these people will be grossly underdeveloped in intellect, society and technology. Old Earth is a famous abandoned planet, and a typical example of one. Despite being abandon for several hundred years, crude communities still exist on its surface, ekking out a miserable existance. Except for a few isolated radios and other interplanetary communication devices, these humans are cut off from the outside universe.