When is it okay to kill an alien life form?
In the movies, the answer is usually pretty simple: self-defense is fine, especially if it inspires an impassioned speech about human exceptionalism. But in the real world, the choice is neither simple nor abstract. Many missions to neighboring planets have the potential to disrupt extraterrestrial life, whether by accident or design. Under what circumstances would the loss of a few alien (admittedly, perhaps microbial) beings be acceptable?
The views on this issue are diverse and intriguing, and important to be aware of in the pursuit of finding life on other planets. Current missions to Mars and upcoming missions to exo-moons, including Jupiter’s moon Europa and Saturn’s moon Titan, could potentially encounter extraterrestrial life. “It’s a question of what our priorities are, whether we’re astrobiologists or the general public,” says philosopher Jamie Johnson-Schwartz. Wrote extensively On the ethics of space exploration.
NASA’s Viking missions, which landed the first robots on Mars in 1976, had a clear answer: It’s okay to kill a few aliens, as long as there’s scientific justification. The Viking landers ran experiments on samples of Martian soil; some were soaked in nutrients, some were sterilized at searing high temperatures. The logic was that hypothetical microbes that received the spa treatment would become active and might show detectable activity, while those roasted by flame would go quiet and serve as a control.
Aside from the fact that the Viking experiments detected signs of life, That is debatable (The general consensus is that the experiment uncovered some interesting chemistry that can be explained without introducing life.) Imagine extraterrestrials coming to Earth, gathering a group of people, treating one group to a fancy meal, and vaporizing another to confirm that the first group were in fact alive. It would be a strange introduction to a new species.
Of course, this thought experiment is incomplete because microbes are generally thought of as disposable at the individual level, unlike complex life forms like humans. But it’s an interesting reflection of our values about first contact: while killing a few microbes here and there is inevitable, whether on Earth or in space, entire ecosystems are a different story.
The Space Research Council, an international non-governmental organization dedicated to space exploration cooperation, Prohibit any activity That would be a threat to the extraterrestrial biosphere, or even to life on Earth. This principle of “planetary protection” aims to avoid the transfer of life on Earth to other worlds (forward contamination) or the return of extraterrestrial life to Earth (backward contamination).
“Viking was extremely careful to avoid introducing any terrestrial organisms that could disturb the existing Martian biosphere,” David Grinspon, senior scientist for astrobiology strategies at NASA Headquarters, said in an emailed response that also included input from Nick Benardini, NASA’s planetary protection officer.
