Formation of Earth
This event, occurring 14 billion years ago, started the universe.
What is the Big Bang Theory
This is the The thin outer shell of Earth where we live.
What is Earth's crust?
This rigid outer layer is broken into tectonic plates.
What is the lithosphere?
This is one of three ways Earth was heated: space rocks hitting it.
What are collisions?
"Foreign rocks" brought to the surface by volcanoes.
What are xenoliths/mantle rocks?
The spinning cloud of gas and dust that became our solar system.
What is a solar nebula?
This is Earth's thickest layer, making up about 84% of Earth’s volume.
What is Earth's mantle?
This is the soft, flowing layer of the upper mantle.
What is the asthenosphere?
This process squeezed material inward, creating heat.
What is gravity/compression?
These are space rocks that offer insights into Earth's core composition.
What are meteorites?
The age of our home planet, Earth
What is 4.6 billion years?
This central layer is made mostly of iron and nickel.
What is Earth's core?
This is the strong, rigid lower mantle kept solid by pressure.
What is the mesosphere?
This long-term heat source involves unstable isotopes of elements breaking down in an effort to acheive a state of equilibrium.
What is radioactive decay?
This is generated by the constant churning of liquid iron and nickle and protects us from radiation.
What is Earth's magnetic field?
This is the force that caused gas and dust to collapse into stars and planets
What is gravity?
This layer's thickness ranges from 5 to 70 km.
What is Earth's crust?
The lithosphere floats on this layer like "crackers on peanut butter"
What is the asthenosphere?
True or False: Radioactive decay still warms Earth today.
What is true?
The material believed to form Earth's core based on meteorites.
What is iron and nickle?
The process where heavy materials sank and light materials rose, forming Earth's layers.
What is Differentiation?
This specific part of the Earth's core is liquid.
What is Earth's outer core?
The depth (in km) where the mesosphere begins.
What is 350km?
The heat of Earth's core is similar to the surface of this object, with an average temperature of 5,500C, 5,800K, or 10,000F.
What is the sun?
This calculation, often shown as p = M/V or D = M/V, proves the core contains heavy metals like iron.
What is density?