Early Earth

Front

According to scientists, both Earth and moon are...

Back

About 4.6 Billion Years Old

Front

What was formed after water vapor condensed to form rain and then gradually accumulated?

Back

Earth's Oceans

Front

Which of the following is not an important part of Earth's second atmosphere? Options: Helium, Oxygen, Water Vapor, Carbon Dioxide

Back

Helium

Front

The earliest form of life known on Earth was...

Back

Single-Celled Organisms

Front

Scientists believe that __________ and the moon are about the same age.

Back

Earth

Front

According to scientists, Earth began as a ball of dust, rock, and __________.

Back

Ice

Front

What force pulled this mass together?

Back

Gravity

Front

A(n) __________________ is a ball of dust, gas, and ice that orbits the sun.

Back

Comet

Front

According to scientists, over billions of years, Earth's ________ have formed, broken apart, and crashed together again.

Back

Landmasses

Front

What happened to Earth's core and crust after the materials pulled by Earth's gravity became very hot?

Back

Melted