Magnetic Reversals: Fact and Fiction.
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Introduction: A recent 2003 movie 'The Core' proposes that if Earth were to temporarily lose its magnetic field, a wide range of deadly calamities would befall humans and living creatures on Earth. What will really happen? Students may have difficulty separating fact from fiction, especially when modern-day science fiction movies seem so believable, and actors have become really good at 'talking science'. |
Here's what CBS News said about The Core in a short synopsis: "In "The Core," the Earth's inner core has stopped rotating, causing the planet's electromagnetic field to rapidly deteriorate. This can cause airplanes to start falling from the sky and everything electronic to be destroyed. And static discharge in the atmosphere threatens to create "super storms." Plus microwave radiation will literally cook the planet." What you should note is the sloppy use of terminology, and the subtle introduction of many 'facts' about what might actually happen as though they are certifiably sound, scientifically. In fact, there is not a single idea in the above paragraph that makes sense. Luckily, we don't have to speculate about what might happen. Over 400 magnetic reversals have been detected by geologists dating back to nearly 330 million years ago. By studying them carefully, scientists are learning about their impacts to Earth. This activity will help students discriminate between factual and fictional descriptions of a natural phenomenon, which has been scientifically studied from the fossil and geologic record of Earth, and found to be a lot less frightening than Hollywood (or CBS News!) would have us imagine! |
Objective:
Students will read to be informed. They will learn about Earth's magnetic reversals by reading two fiction stories and a scientific summary of past reversals, including graphical information.
Materials:
Story 2...."The Turning Point"
Story 3..."Magnetic Reversals: Back to the Future?"
Vocabulary Transparency Master
Vocabulary:
Magnetic Intensity
Magnetic Polarity
Magnetic Reversal
Magnetic Field
Electromagnetic Field
Ionosphere
Aurora
Plasma
Microwave
Procedures: