The Moon's far side and visible side exhibit significant differences in their geological features and surface characteristics, primarily due to their history of impact events and volcanic activity.
Visible Side of the Moon:
- Maria Coverage: Approximately 30% of the visible side consists of lunar maria, which are large, dark basaltic plains formed by ancient volcanic eruptions. These maria were created by the flooding of impact basins during the Moon's history, particularly during the late heavy bombardment period.
- Impact History: The visible side of the Moon has been heavily impacted by asteroids and comets over billions of years, resulting in a diverse landscape with many large craters. These impacts have contributed to the formation of the maria by producing extensive basins that later filled with lava.
- Crater Density: The visible side has a higher density of craters, including both large and small ones, due to its exposure to space debris. This contributes to a varied landscape that showcases its active geological history.
Far Side of the Moon:
- Maria Coverage: The far side, in contrast, contains only about 1% maria. The most significant feature is the South Pole-Aitken Basin, one of the largest impact structures in the solar system, but it is not as extensive in volcanic plains as the maria on the near side.
- Surface Characteristics: The far side is predominantly characterized by a rugged, heavily cratered terrain. It lacks the extensive basalt plains found on the visible side, which suggests a different history of volcanic activity and fewer large impacts that might have produced maria.
- Impact History: The far side has also experienced impacts, but the distribution and effects are different, resulting in a surface with more mountainous highlands and fewer low-lying areas than the near side.
Summary:
- The visible side of the Moon is marked by extensive maria covering a significant portion of its surface, a result of volcanic activity following asteroid impacts. It also displays a higher density of craters.
- The far side, while still bombarded by impacts, is characterized by a more rugged landscape with fewer maria and a predominance of highlands and craters, indicating a distinct geological evolution.
In essence, the differences between the two sides provide valuable insights into the Moon's formation and history, shedding light on the processes that have shaped not just the Moon but other similar celestial bodies in the solar system.
1 answer