Vacancy in Mars Planet ?

In USA posters have been pasted calling applications for vacancies in the field of Agriculture , Geology, and research. These posters were displayed under the name of NASA . Whether this posters have been displaced by NASA or others are yet to be determined. However, NASA has not disclaimed these  posters . Posters stated that selected candidates should be prepared to be away from his / her family for a long time. The question arise is whether they will be able to return to earth live?