"Plate tectonics" refers to when the outer layer of a celestial body, such as a planet or moon, is made up of a crust of plates that move over time. The only known celestial bodies with plate tectonics are Earth and one of Jupiter's moons, Europa. Earth’s plates are made up of rocky plates that are thought to have shifted throughout history, causing earthquakes and resulting in separate continents, volcanoes and mountains. Europa is thought to have plate tectonics as well, but with a crust made of ice rather than rocks. Some scientists believe that this means that it could be suitable for human habitation.
More about plate tectonics:
- Plate tectonics on Earth causes carbon from the atmosphere to be absorbed and carried back under the ground; otherwise, the planet might overheat from greenhouse gas emissions.
- The ice plates of Europa are estimated to be one of the youngest surfaces in the solar system at an age of 40 million to 90 million years.
- An area in Chile known as the Chile Margin Triple Junction is home to the only active modern example of plate tectonics, with a plate shift of about 3.15 inches (80 mm) per year.