NASA: Mapping Magnetic Fields
We highly recommend this video-based tutorial produced by PBS and NASA on how magnetic fields are mapped. The text background explores how Earth's solid inner core and the planet's rotation act to create convection currents in the liquid outer core, generating an electric field which, in turn, produces a magnetic field. The 3-minute video explains how spacecraft use magnetometers to measure external magnetic fields on Earth and other planets in our solar system. Magnetic fields of the Sun, Earth, Jupiter, and Mars are compared. This resource includes tips for teachers and discussion questions.
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NASA: How Mars Became a Desert
First a caveat: We don't know exactly how Mars turned into a barren, arid, withered-looking planet. Evidence shows it wasn't always that way. This video-based tutorial from NASA Planetary Sciences delves into current scientists' theories about what happened to Mars. One theory is that asteroids orbited Mars long ago, creating an internal dynamo that produced a magnetic field and an early atmosphere. So what happened? A leading theory is that a large asteroid crashed into Mars, stripping away its atmosphere and destroying its magnetic field. This resource includes a 5-minute NOVA video, background information for students, teaching tips, and well-crafted discussion questions.
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Windows To The Universe: Detecting Planetary Magnetism
Concise, yet informative tutorial on magnetic fields existing on planets and moons in our solar system. Produced by the respected Windows to the Universe education project, this page could serve well as a 10-minute introductory reading exercise to supplement the lab featured in this Digi Kit: "Modeling Planetary Magnetism".
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