Exoplanets Could Help Us Learn How Planets Make Magnetism

For decades, astronomers have been perplexed by planetary magnetic fields. In our own solar system, there is no rule that explains which worlds generate these magnetic sheaths: Earth, for example, has one, but its sister world — Venus — does not. Astronomers suspect that one of the best ways to understand the mysteries of magnetism might be to study worlds orbiting other suns.

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