Birth of the Earth Quiz

Planets first began forming due to

• gravity

• electrostatic charge

• clumping

The earth is (a)   billion years old

When clumps get to about __ in diameter, gravity takes over to make planets grow.

• a mile

• half a mile

• a kilometer

• 3 miles

The earth's spinning core creates __.

• a magnetic feild

• the aurora

• weather

The magnetic feild protects us from __.

• solar wind

• ultraviolet

• ozone

Seasons are caused by __ that occured when Earth was struck by a Mars sized object early in its formation.

• the Earth's tilted axis

• the Earth's vertical axis

• the earth's changing distance from the Sun

How did the Earth's Moon form? Please explain your answer using at least 3 sentences.

By studying a well-preserved meteorite, scientists discovered meteorites contain (a)   percent water.

Explain where earth's water came from. Use at least 3 sentnences to explain your answer.

Stromatolites (made of blue-green bacteria) dominated the world for over 2 billion years. What gas did they produce that reacted with iron in the ocean?

• carbon dioxide

• methane

• oxygen