Much of the challenge of communicating scientific concepts to the public at-large comes in attempting to find ways to make ideas easily digestible.
When talking about human space exploration, the possibility of finding extraterrestrial life, or the recovery of cultural artifacts from non-terrestrial sources, the concept of planetary protection is key. Basically, planetary protection stresses the importance of working to prevent the spread of biological contamination between worlds.
However, for those who are unfamiliar or who would prefer a succinct example to a rehash of the technical definition, allow me to take a stab at an explanation less esoteric: Planetary Protection in terms of Michael Crichton and H. G. Wells.
As arguably two of the most well-known science fiction authors of the 20th Century, it seems only fitting that each penned a story that together provide planetary protection’s two worst-case scenarios. [[PLOT SPOILER ALERT]]
In Crichton’s “The Andromeda Strain,” a returning military satellite inadvertently carries with it an extraterrestrial pathogen, with fatal consequences for a retrieval team as well as a small Arizona town. This is a prime example of the dangers of returning to Earth from an extraterrestrial environment, and why planetary protection measures are important for us.
On the other side of the coin, in H. G. Wells’s “The War of the Worlds,” invading extraterrestrials, despite demonstrating an extreme level of technological advancement, are ultimately defeated by terrestrial pathogens due to their lack of planetary protection measures.
So, in short, (using Wells and Crichton as guideposts,) planetary protection is intended to prevent:
- our being harmed by alien bugs
- potential aliens from being harmed by our bugs.
To the point, the last thing we want to do is go to Mars searching for life, only to inadvertently kill it, or worse, track it back home so that it wreaks havoc on our ecosystem.
That’s it. You can say it all between The War of the Worlds and The Andromeda Strain. Planetary protection in a nutshell.
Chronicles of an Atomic Astrowright 
It does seem rather unlikely that we would infect each other, I mean for us humans, our primary method of getting infected is other humans, either directly, i.e. STDs, most colds, or indirectly, i.e contaminated food. So far as I’m aware, we don’t get illnesses from insects (I’m ignoring mosquitoes as they are carriers of disease) or squid, for example. And, compared to whatever the hell we find on Mars, we’re pretty closely related to them. I’ll admit, I’m no biologist or MD, but it doesn’t seem likely that a foreign microbe would infect us all that easily because we are a pretty hostile environment.
Alexander,
You’re completely correct. This is the flip side of planetary protection, which is the argument that the pathogens we have to worry about are a result of parallel evolution. In this light, “alien” bugs might have to mechanism to even interface with our biology, much less cause us harm. The terrifying thought in this scenario, however, comes in the event that biology on Mars and Earth are related, (i.e., the idea of panspermia, where life evolved on Mars and then was blasted to Earth via meteorite after an impact eons ago.) In this case, the biology of life on Mars would be distantly related to ours (use of DNA/RNA, amino acids, basic biochemistry, etc.,) but separate enough (via time) for us to possibly have no active defenses against it. Food for thought.
So, again, you’re absolutely right that the devil is in the details about the true utility of planetary protection. Hopefully, however, you agree that as a first-blush introduction to the idea, Crichton and Wells can take a person pretty far.
Thanks for reading – critical feedback is always quite welcome!
Cheers,
Ben
I agree, it is quite a scary scenario. I’m just sick and tired of so many sci-fi works having disease from alien world (or, in some cases, disease from distant past/deepest depths of the ocean) being so incredibly deadly to us.
I understand your frustration. However, know that my post was aiming for those who weren’t already familiar with planetary protection… Covering the current debate in planetary protection reasoning is down the road a ways. 😉