It takes a special kind of person to join the military, but it takes a much different sort to volunteer for a mission to Mars.

For a few select soldiers, life after service won't be about transitioning back to civilian life but adjusting to the harsh terrain and low oxygen on the surface of the Red Planet. The Department of Defense spoke to two members of the military who have made it to the final round of candidates for Mars One, a one-way mission that hopes to colonize the planet for long-term human habitation.

Out of 200,000 applicants, Mars One selected 1,058 finalists. That number includes MC2 Brooks Slaughter and 1st Lt. Heidi Beemer. As finalists, they will begin a ten-year training period that includes lessons in self-sustaining farming, component repair for the modules they'll be living in and basic medical procedures, according to the Mars One website.

Still, many might see a one-way ticket to Mars as an odd choice for a soldier's life after military service. Not for Slaughter and Beemer, though, who couldn't be more thrilled with the opportunity.

"I believe that when it does happen," Beemer told the DoD's Science blog, "it's going to be the biggest thing that ever happens to us as humans."