Core Formation on the Terrestrial Planets: Comparative Planetology
نویسندگان
چکیده
The Boundary Conditions: Basalts from the Earth, the Moon, Mars, and Vesta are strongly depleted in elements that prefer to reside in the metallic state (siderophile elements). Therefore, it is believed that all these bodies have metallic cores. We do not yet have siderophile element analyses of venusian basalts, but we assume that Venus, too, as a terrestrial planet, has a metallic core. For the Earth, Moon, and Mars, the moments-of-inertia of these bodies are consistent with metallic cores of various sizes. Because Venus rotates so slowly, it may be difficult to determine the moment-of-inertia of Venus in order to confirm this assumption.
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