What great tools are Blogs and Twitter! I twitted about my previous blog post “Blowing Head!” and on the second day, after about 150 people had read the post and left positive comments (not all 150 actually), I get a Tweet back from Ashley Kent (@AshleyKent), who not only too the time to read my post, but also pointed out that NASA research suggests that a human body would not explode, or freeze immediately, in Space. Ashley gave me this link that explains some of these findings and tests made by NASA.
My previous post doesn’t mention exploding bodies actually, it just asks questions, so I could just tell you that of course I knew, but I would be lying. It was an interesting surprise to me to find out what NASA has discovered and predicted. However, there are some effects of exposure of a human body to vacuum which resemble what happens in tea cake in the vacuum coffee saver, as suggested by this article. An interesting part of the article says:
“When the human body is suddenly exposed to the vacuum of space, a number of injuries begin to occur immediately. Though they are relatively minor at first, they accumulate rapidly into a life-threatening combination. The first effect is the expansion of gases within the lungs and digestive tract due to the reduction of external pressure. A victim of explosive decompression greatly increases their chances of survival simply by exhaling within the first few seconds, otherwise death is likely to occur once the lungs rupture and spill bubbles of air into the circulatory system. Such a life-saving exhalation might be due to a shout of surprise, though it would naturally go unheard where there is no air to carry it.
In the absence of atmospheric pressure water will spontaneously convert into vapor, which would cause the moisture in a victim’s mouth and eyes to quickly boil away. The same effect would cause water in the muscles and soft tissues of the body to evaporate, prompting some parts of the body to swell to twice their usual size after a few moments. This bloating may result in some superficial bruising due to broken capillaries, but it would not be sufficient to break the skin.”
So, it might not be as dramatic as it looks in the demo in my previous blog post, but the demo is certainly a very interesting activity that could be turned into a great investigation of the effects of a vacuum on different materials and tissues. We have the opportunity here to do some real Science with our kids and pose some questions that will really challenge their experience and create a metacognitive conflict, which will make the activity even more interesting and enjoyable for them!
Any suggestions on the things we could stick inside this coffee saver vacuum chamber? What about simulating a lung in vacuum with a balloon? Where is the limitation of this analogy? What would happen if the balloon were filled with water? Please make your suggestions…