Only one individual holds the cool job title of planetary protection officer. Dr. Catharine "Cassie" Conley's job is to keep space safe from contamination and to keep Earth safe from potentially hazardous alien life.

The role of planetary protection officer is important because space travel could be harmful to our solar system. If precautions are not taken, astronauts and equipment could contaminate extraplanetary objects and jeopardize our understanding of alien environments. Not only could microbes from Earth cause harm to life on other worlds, but life and alien substances brought back to Earth could be dangerous and would need to be treated with extreme caution. No one wants an alien invasion — even of the teeny-tiny alien variety. Fortunately, there are international rules in place to prevent such calamities.

Protecting space has been a subject of concern at the international level since the beginning of the space race, and as such, the Outer Space Treaty was created in 1967. It was based on the previous Declaration of Legal Principles Governing the Activities of States in the Exploration and Use of Outer Space, according to the United Nation’s Office for Outer Space Affairs. The Planetary Protection Office was created in 1976 after the Viking missions to Mars raised concerns about contaminating the Red Planet.

As we set our sights on manned missions to Mars, these policies become even more important. In addition to making sure that international guidelines for exploring extraplanetary objects are upheld, Conley and the rest of NASA's Office of Planetary Protection also coordinate the efforts of space explorers — from NASA missions to the endeavors of private companies — to keep space (and Earth) clean.

Conley, who holds degrees from MIT and Cornell, has been involved with NASA since 1999 when she worked at the space agency's Ames Research Center. Conley's involvement in planetary protection began with the Space Shuttle Columbia disaster in 2003. One of her experiments which contained live nematodes was on board the shuttle, and the nematodes survived. Conley was appointed as planetary protection officer in 2006 and has been protecting places like Mars even since.

In a video provided by NASA, Conley explains that before we could do something like terraform Mars, we would first need to understand how life on Mars functions.

"You can't do a do-over on releasing organisms in the Mars environment. Once they're there, they will be there. So, we have to do all of our search for life activities. We have to look for the Mars organisms without the noise of having released Earth organisms into the Mars environment."

In fact, this concern came up recently when NASA forbade the Mars rovers from investigating newly discovered water on the planet. The current rovers are deemed too "dirty" to be allowed near the areas that contain evidence of Martian water.

Other concerns involve what to do with spacecraft after their mission ends. It's dangerous to have a defunct craft wandering amok in the solar system, potentially causing harm to extraplanetary objects, so there are plans in place for responsible self-destruction. For example, the Cassini orbiter, which is studying Saturn and its moons, already has a planned disposal. The New York Times reports, "Cassini will be sent on a death dive into Saturn, where heat and pressure will obliterate it and any remaining microbes."

So, we can thank Conley and the Office of Planetary Protection for keeping our solar system safe and clean. It would seem that the motto "tread only lightly, take only pictures" is good advice, even in outer space.