Earth's Layers: Core, Mantle, Crust
The Core, Mantle, and Crust are Earth's Layers.
- In 1692, Edmond Halley (of comet fame) proposed that the Earth is hollow!
- At Earth's center is an iron-rich orb more than 4,000 miles wide—bigger than Mercury, actually—closer to our feet than L.A. is to New York.
- The inner core is nearly as hot as the surface of the sun, YET it is solid due to the pressure down there being 3 million times what it is on the surface.
- The deepest place ever reached by human technology is the Kola Superdeep Borehole near Murmansk, Russia.
- Reduce, reuse, recycle. The slow churn of plate tectonics pulls crust into the interior, where any plant and animal life in it gets trapped and cooked. Organic material eventually resurfaces in lava and volcanic gases, including atmosphere-warming carbon dioxide.
- Such cycling, and the protective magnetic field generated by the core, keep our planet at the perfect temperature for life.
- Look at Venus, with its 900-degree Fahrenheit days and nights. If not for our planet's restless insides, that could be us.