Astronomy Chapter 8

The Van Allen belt is...

a region of trapped charged particles in the Earth's magnetosphere

Today, a significant amount of new gas is joining the atmosphere of the Earth from what source:

volcanoes release gas that was trapped within the Earth

T or F: convergent, plates move apart (oceanic ridges)

false

T or F: slow motions within the mantle of the Earth move large sections of the mantle around caused the plate tectonic

false

Which of the following is a way we believe that the early atmosphere of the Earth differed from the atmosphere we have today?

-there was little if any free oxygen early on -there was no ozone layer early on -there was probably more carbon dioxide early on than there is today

If no one has ever visited the core of the Earth, how do we know that it is made of metals?

circulating liquid metals in the core set up a large (measurable) magnetic field

Which part of the Earth has the greatest density?

core

Any rock in the Earth's crust that has cooled from an originally molten state is called...

igneous

Asteroids are made up of _________ and ________ material

metals, rocky

The most abundant gas in the Earth's atmosphere is...

nitrogen

In which region of the Earth's atmosphere have you spent most of your life?

the troposphere