Bombardment era of cratering about 4 billion years ago. Ejection of many planetesimals from gravitational influences. For the Earth, the differentiation was followed by cratering , and then flooding as decay of radioactive elements heated the interior and lava flowed. Later, when rain began to fall, the basins were filled with water. Condensation hypothesis - Earth and moon from the same cloud.
Problem is that Earth and Moon have different compositions.
Running Paper on Greenhouse Effect. Describe how the Greenhouse Effect is produced on a planet. Distinguish between visible radiation and infrared radiation. Discuss with your partners what you know about global warming . Write down one or two ideas.