|MadSci Network: Earth Sciences|
Dear Charissa: Scientists have determined the internal structure of the Earth by studying the travel of seismic (earthquake) waves. The behavior and velocity of seismic waves is dependent on the material through which they are travelling. Some waves slow down or do not even travel through some materials, while other types of seismic waves travel very fast. From studying these waves scientists have been able to produce an image of the structure of Earth's interior. Best Regards, Rick De Van firstname.lastname@example.org [Moderator note: There has been a proposal to use particles such as neutrinoes and muons to probe the interior of the Earth in a manner similar to how a CAT scan can image the human body. If this is at all practical, it will take a few years to develop.]
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