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For every week since 2002, Planetary Radio has visited with a scientist, engineer, project manager, advocate or writer who provides a unique perspective on the quest for knowledge about our solar system and beyond. We also showcase regular features that raise your space IQ while they put a smile on your face.

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Hope for Pluto—Should We Re-Redefine Planets?

March 08, 2017 • 33:51

Planetary geologist Kirby Runyon is lead author of an abstract that proposes a new, geophysical definition of what a planet is.

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