This summer, the National Aeronautics and Space Administration will launch a rover designed to collect samples of the Martian surface and store them until they can eventually be brought back to Earth. When they arrive, according to a former NASA scientist, they’ll be "quarantined and treated as though they are the Ebola virus until proven safe."
His statement caused a minor media sensation, and understandably so. In the midst of one pandemic, Americans aren't ready for another imported from outer space. But ready or not, the United States and other spacefaring nations need to start updating planetary-protection measures for a new era of spaceflight.
In the years ahead, NASA's Mars initiatives will likely be emulated by other countries. Ambitious private space companies are eager to follow with their own robots (and perhaps, eventually, humans). Clearer safety guidelines are essential both for protecting Earth and for ensuring that a wary public is comfortable with humanity's next steps into the solar system.