H&Co. Ezine -
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Published on: 6/14/2001
Last Visited: 1/19/2002
Getting this right will require careful stirring, warns Cary Forest, a physicist at the University of Wisconsin in Madison.The flow has to have a particular character in order to generate a self-sustaining field."If the flow is not right you're not going to get a dynamo," he says.Get the flow wrong and you could end up simulating the core of the wrong planet.Although Earth and Venus are similar in size and basic composition, Earth has a field while Venus doesn't.No one knows why, but flow might be the key.
They may not know the precise recipe for successful flow, but theorists believe there are two essential ingredients.The first appears to be differential rotation, which will stretch any stray magnetic field lines around and around the axis, like a kid stretching a wad of chewing gum round and round his finger.
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Meanwhile, Forest intends to roll out his 1-meter ball at Wisconsin this summer, and believes he will be first to generate the dynamo effect in a freely flowing fluid.