By Sara Thompson
Special to the Enterprise
Our planet has so many interesting things on the surface. Vast oceans, challenging climates, an infinite array of plants and animals calling the surface home. Under the Earth’s surface is just as interesting. The interior of our earth is made up of different layers, each with their own purpose to keep the planet working.
The outermost layer is the crust. This is the surfaces we live on including the tallest mountains and the ocean floor. The crust is the thinnest layer but can still range between 3 and 44 miles thick! The crust is broken up into different tectonic plates, that slowly move and rotate. This movement causes mountains to rise, volcanos to form, and earthquakes.
The next layer is the mantle. The mantle makes up over 80% of the Earth’s volume and nearly half of the radius. It extends from the crust to a depth of nearly 2,000 miles! The upper part of the mantle is mostly solid but has some liquid due to the melting of rock. This slightly molten portion is responsible for the movement of the tectonic plates and the generation of magma. Not much is known about the rest of the mantle, as it is too deep for us to explore, but seismologists can track the changes in seismic waves that travel through the mantle as the density and consistencies change.
At the innermost portion of our planet is the core. It has a defined outer and inner portion, each with different properties. The outer core is liquid and about 1,400 miles thick. The fluid movements in the outer core are what generate our geomagnetic fields. The inner core is a solid metal alloy. Thought to be a combination of iron, nickel, and other heavy metals, it is believed that while the planet was forming, these heavy metals combined and sank to the center of the earth during the surface cooling. The boundary between outer and inner core is approximately 3,200 miles below the Earth’s surface.
The campers at this week’s ‘Stones & Bones’ summer camp learned about the different layers of the Earth and the different types of rocks. They also learned how fossils form, made their own plaster fossil impression, and discovered how dinosaurs got their names.
Last day to visit our exhibit “Explorit Rocks!” and explore rocks, fossils, minerals, and crystals is Friday, August 18. Open to the public on Fridays from 1-4pm, Saturdays and Sundays from 10am-2pm. Admission is $5 per person. Explorit Members, ASTC, and those age 2 and under free.
Explorit's coming events:
• Explorit will be CLOSED to the public August 19-September 1 for the installation of our next exhibit.
• Grand Opening of “Our Wild World” is the weekend of Saturday, September 2 – Monday, September 4, 10am-2pm each day. Admission is $5 per person. Explorit Members, ASTC, and those age 2 and under free.
• Now is a great time to donate and help Explorit continue to educate and inspire the scientists of tomorrow: https://www.explorit.org/donate
• A Membership to Explorit grants the recipient free visits to Explorit’s regular public hours, discounts on events, summer camps and workshops, and gives you ASTC benefits