Planet Structure Quiz

What is the main reason for the different layers of density in planets like Earth?

• Temperature variations

• Radioactive decay

• Nuclear fusion

• Gravitational pull

What is the least dense part of Earth's structure?

• Atmosphere

• Inner core

• Crust

• Mantle

Which heavy element is the most stable element produced outside of a supernova?

• Gold

• Iron

• Nickel

• Carbon

What caused the heavier materials like iron and nickel to work their way to the core of proto-Earth?

• Gravity

• Nuclear fusion

• Radioactivity

• Convection currents

What is the likely state of the iron in Earth's inner core?

• Gas

• Liquid

• Solid

• Plasma

What creates a magnetic field that shields Earth from the solar wind?

• Liquid outer core

• Atmospheric pressure

• Convection currents

• Radioactive decay

What is the main reason for Earth's continued cooling and shrinking?

• Solar radiation

• Liquid outer core turning solid

• Atmospheric pressure

• Convection currents

According to Carl Sagan, what has taken its density into its own hands?

• Animals

• Humans

• Planets

• Stars