There are many thought-provoking moments in the new movie The Martian.
From the nature of human endurance to questions of science and politics, it's a film that deserves the success it has gained (how many films can throw around terms like hexadecimal and Hohmann Transfer like you already know them).
But unspoken, behind the film, is a truly profound question about humanity's next steps into the solar system.
At one point in the film, the stranded astronaut Mark Watney (played by Matt Damon) must figure out how to heat his rover for long trips without draining the battery. He solves the problem by digging up the radioactive generator the crew used on their way to Mars, which they had buried for safety reasons. It was at this moment that I remembered the long, simmering debate about the ethics of colonizing Mars (or any of the other worlds in the solar system).
Even if NASA never thought to include a radioactive generator on a Mars mission, the question of us, our stuff, and untouched planets would still remain. We can discuss this issue at three levels:
1) Is it OK for us to disturb these worlds with our machines (rovers, etc.)?
2) Is it OK to disturb them with human explorers?
3) Is it OK to develop full scale human "colonies" on these worlds?
It's important to note that no matter what we do in terms of sterilization, it's possible that some of Earth's microbes may survive the journey across space and land with our rovers. NASA spends a lot of time worrying about this. They even have an Office of Planetary Protection that develops protocols for cleaning up the machines we send to Mars.
The main reason for planetary protection is not ethics but, rather, science. If we are looking for life on other worlds, we need to be careful we don't become contaminated with bacteria we brought with us — or contaminate Earth with something from another world via "sample return" missions.
While these scientific questions are important in their own right, the question we are asking about today is much broader and much deeper.
It is possible that Mars still has microbes scraping out a living in its nooks and crannies (underground would be the best bet). So, what are our responsibilities to that life if it exists?
Must we be sure that human exploration poses no planetary risk to potential Martian life before we set up shop and begin exploration? Consider the fact that once human beings are on Mars, we'll be trailing some parts of our (or Earth's) microbiome wherever we go. What if our activity introduced new life on the planet even at the lowest levels? What if our activity causes the death of some life already there even at the bacterial level?
Is that OK?
Looking further into the future, we hit the really big question. What if we reach the point where large-scale human habitation of Mars becomes possible? Do we have a right to change a planet where we did not evolve? On the other hand, aren't we citizens of the solar system just as much as the microbes on Mars? If we bring the possibility of turning Mars from a dead world (or a world with a very thin biosphere) into one where life thrives, isn't that a kind of moral imperative, too?
What do you think?
Adam Frank is a co-founder of the 13.7 blog, an astrophysics professor at the University of Rochester, a book author and a self-described "evangelist of science." You can keep up with more of what Adam is thinking on Facebook and Twitter: @adamfrank4