How much of what you know about science comes from school, university, scientific papers, cool blogs and radio shows, and how much comes from movies and TV shows?
This question was put to the test by researchers from Boston College, USA. Using members of an 8th grade science class who had studied the structure of the Earth, they exposed half of them to the Hollywood movie The Core (2003), then compared how much their understanding changed compared to students who were left unsullied.
The results showed that explanations given by the main scientist character (played by Aaron Eckhart) were accepted because they sounded plausible and hey, he looked plausible. But also, what the students saw in the movie was more memorable and often replaced what they learned in class.
As examples, take the following quotes from post-movie interviews.
Interviewer: Great. Now could you explain for me what the Earth’s magnetic ﬁeld does?
Student: It keeps the Earth safe from microwaves.
Interviewer: Microwaves? How does the Earth’s magnetic ﬁeld keep us safe from microwaves?
Student: Umm, not sure, but I know that if the Earth’s magnetic ﬁeld wasn’t there the microwaves would get through the atmosphere and cause a lot of damage.
The Earth’s magnetic field does deflect and trap charged particles emitted by the Sun, the so-called solar wind. But the solar wind is definitely not microwaves, which are electromagnetic radiation, have no charge and are completely unaffected by the magnetic field.
…I think it [the science] was, or could be mostly right. Some of it was a little strange. I don’t think scientists know how to dig through rock that easily or else we would have heard about it on the news or read about it in our book or Mrs. Kennedy would have told us about it. I also always thought that the aurora was caused by the magnetic field someway but in the movie they were caused by something else [in the movie the aurora was caused by high altitude static discharge]. It sounded right but I am not sure.
Well, firstly, no we can’t dig through rock that easily: the deepest humans have drilled so far is 12,262 metres (the good-old Kola Superdeep Borehole). And the aurora is caused by ions and atoms excited by solar wind, trapped by the magnetic field and and hitting the upper atmosphere.
Interviewer: Can you tell me what each layer is made out of?
Student: Sure. The very inside is mostly rock and iron and is very hot. The next layer is mostly liquid though it probably has big chunks of rock or maybe diamonds or something like that.
Interviewer: Why diamonds?
Student: The pressure is very high there and that is how diamonds are formed, under high pressure.
Why diamonds indeed? As far as we know, the liquid outer core is mostly iron and nickel, with possibly some sulfur and oxygen. Whereas diamonds are crystallised carbon: and apart from the likely lack of carbon in the outer core, diamonds are formed in the upper mantle at pressures of 4.5–6 gigapascals and temperatures between 900 and 1300 °C, which is much, much less than the outer core temperature of 4400–6100 °C.
Interviewer: So what causes the magnetic ﬁeld?
Becky: Well… Hmm, wait… I got it. It has to do with The Core, the outer core. It is a liquid metal and it has a lot of electrons. Electrons are what make electric current. And electric current makes a magnetic ﬁeld. Bingo!
This is kind of true. The mechanism that generates the Earth’s magnetic field is not completely understood, but it’s based on dynamo theory, and relies on not only the rotation of an electrically conducting fluid, but convection due to heat too.
Generally, the researchers concluded that movies like The Core are less useful for delivering real facts than they are for providing examples of incorrect science for students to dissect. Learning from their mistakes, you could say.
Barnett M, Wagner H, Gatling A, Anderson J, Houle M & Kafka A, “The impact of science fiction film on student understanding of science”, Journal of Science Education and Technology, vol. 15, no. 2, April 2006 [PDF 228 KB]