Pre-viewing questions
- What is 270 million miles (mi) in kilometers (km)?
- What is 800 pounds (lbs) in kilograms (kg)?
- What is 23,000 miles (mi) in kilometers (km)?
Watch the video from 26:25 to 33:00, and answer the questions below.
Birth of the Earth (50:05)
Questions
- What physical phenomenon causes Earth to have seasons?
- What causes tides on Earth?
- How much water was there on early Earth?
- Why was the early inner solar system bone dry?
- What is the name of the unmanned probe that hit a comet?
- Why have comets been discredited as the source of water on Earth?