Earth’s Moon and Lunar Phases

The Moon shown next to the EarthFrom the beginning of human history, humans have aligned different celebrations, ceremonies, and even myths to the size and brightness of the Moon. Hundreds of satellites orbit the Earth, but only one, the Moon, is a natural satellite. Earth's Moon revolves around the Earth once every 29.5 days, causing its appearance from Earth to change on a nightly basis. This nearly month-long cycle is referred to as the phases of the Moon. Through telescopes and missions to the Moon, astronomers have spent much time observing and studying Earth's closest neighbor in space. In this topic, you will study Earth's Moon and how it formed. You will also explore the Moon's unique geological features and study the cycle of lunar phases.

Essential Questions

  • How did the Moon form?
  • What are the features and composition of the Moon?
  • What causes the lunar phases?
  • How does the Moon affect tidal changes on Earth?