Science Fiction Problems: The Vacuum of Space (Don’t hold your breath)
I was trudging around the internet when I discovered a very interesting article written by Nebula and Hugo award-winning science fiction writer (among a great many other accolades) Geoffrey Landis. The article explains the issue of explosive decompression (the instant or very rapid removal of atmosphere, in this case from a plane or spaceship cabin), the effects of a vacuum on the human body, and all the myths and misunderstandings thereof. I was so intrigued by the wild disparity between common assumptions and hard science on this topic that I saw fit to condense this very well-referenced but otherwise fairly inaccessible article into a happy little summary, for the benefit of our readers. Be sure to check out the articles for more details if you can stomach the science-speak (Landis is a Doctor of Physics) and definitely take a look at his website, especially his books if you like hard science fiction.
The Hazards of The Black
As I assume most (hopefully all) of you know, there is no air in space. There are trace particles, but beyond the atmosphere of our planet, only a void exists, lacking any breathable air. Lack of air not only means no breathing, but also exerts an ambient force, like a vacuum cleaner pulling in all directions. Science Fiction movies and books have used the threat of unprotected exposure to open space for decades, but most rely on rumors and uneducated guesses as to what actually happens when someone gets shoved out an airlock without a space suit.
You can survive exposure to space (for a little while)
Apparently it is possible (assuming you don’t hold your breath) to remain conscious in a complete vacuum for 9 to 12 seconds, and alive for a short time after until you die of Hypoxia, better known as oxygen deprivation. Landis cites several examples of human exposure to extremely low and null-atmosphere decompression where not only do the victims survive, but fully and rapidly recover. One technician was accidentally exposed to almost null decompression, lost consciousness after about 12 seconds, and was rescued after almost 30 seconds when the pressure was finally restored. He fully recovered later.
This is not to say that you cannot die instantly from exposure to a vacuum- if one were to hold their breath, for example, thanks to the extreme difference of air pressure, the lungs would explode, killing the victim instantly by sending large pockets of air to his heart and brain. The article also points out that several animals subjected to decompression suffered immediate heart attacks that killed them on the spot due to the shock. The point is, there is nothing about a lack of atmosphere that means immediate death in every case- as long as you don’t hold your breath.
You will not freeze and/or your blood will not boil
This has been flubbed in lots of movies, but each case simply doesn’t agree with the facts. There is an arguement that due to the lack of air pressure, the boiling point of blood in the human body is lowered enough that if a person was exposed to open space without protection, his blood would actually boil at its normal temperature of 98.6 degrees. This would do all kinds of nasty things biologically which would ensure a painful death, but realistically (as Landis explains), the boiling point would not be lowered enough to cause this traumatic effect.
Similarly, according to Landis, space is not actually cold. Temperature is measured based on air pressure, and so without an atmosphere, space cannot actually be cold, or hot for that matter. Space, as a vacuum, is actually an excellent insulator (think thermoses), so there is nothing about it that would freeze a human body solid as soon as it exits the ship without a space suit. Liquids would freeze at higher temperatures, forming ice in space due to the lack of air pressure, but solids remain stable.
There are plenty of other examples of the realities of vacuum exposure in this article (not to mention the time-tested favorite, explosive decompression), so be sure to check out the link above. It is my sincere hope that anyone reading this, having been enlightened by this important insight, will not make the same mistake that so many cheesy science fiction movies have in their own stories.
Posted on December 8, 2010, in Cliches, Erik Marsh, Geoffrey A. Landis, Science Fantasy, Science Fiction, science fiction problems, World Creation, Writing Hints and Helps and tagged blood boiling, explosive decompression, freezing, science fiction, science fiction problems, space, survival, vacuum of space, writing science fiction. Bookmark the permalink. 12 Comments.