Plans for long-term space missions to and the colonization of Mars are already underway. On December 5, NASA launched the Orion spacecraft and NASA Administrator Charles Bolden declared it "Day One of the Mars era." The company Mars One (along with Lockheed Martin and Surrey Satellite Technology) is planning to launch a robotic mission to Mars in 2018, with humans following in 2025. 418 men and 287 women from around the world are currently vying for four spots on the first one-way human settlement mission.

But as we watch with interest as this unfolds, we might ask ourselves the following:

• Is it ethical to expose people to unknown levels of human isolation and physical danger (including exposure to radiation) for such a purpose?
• Will these pioneers lack privacy for the rest of their lives so that we might watch what happens?
• Is it ethical to conceive or birth a child in space or on Mars? And, if so, who protects the rights of a child not born on Earth and who did not consent to the risks? If we say no to children in space, does that mean we sterilize all astronauts who volunteer for the mission?
• Given the potential dangers of setting up a new colony severely lacking in resources, how would sick colonists be cared for? And beyond bioethics, we might ask how an off-Earth colony would be governed.