The Moon

What is the origin of the Moon?

What do we know about the early history of the Moon and what can it tell us about Earth?

The Moon has served as a beacon in the night sky and fascinated humanity for millennia. We have also been wondering for just as long how exactly the Moon was formed. Among many theories, scientists believe that the Giant Impact Hypothesis provides the best explanation to the formation of Earth’s celestial companion. 

In the early years of the solar system, there were multiple “protoplanets”, not fully formed planets and they were darting around causing all kinds of chaos. The Giant Impact Hypothesis points the finger at a Mars sized protoplanet named Theia that collided with a young Earth. Their devastating impact would have ejected a massive amount of debris into orbit around Earth. Over time, gravity would have pulled this material together into one spot, gradually forming what we now recognise as the Moon. 

This grand story is supported by a few key pieces of evidence found on the Apollo missions and the Moons’ core. Samples of moon rock show similarities in materials with the Earth’s mantle, indicating a common origin for both. Similar to Earth, the Moon also has a molten iron core that would have been carried over from the early protoplanet, Theia. Finally, simulations and calculations have also shown that the size and orbit of the Moon is consistent with a Giant Impact.

Co-formation is another popular theory, where both the Earth and Moon formed from the same protoplanet, slowly over time splitting to form a large planet and a smaller satellite orbiting each other. Some believe that the Earth could have captured a passing celestial body or that a proto-Earth could have spit out debris to form the Moon, but these theories are less popular.

Regardless of the Moon’s formation, it played a crucial role in the Earth’s development and shaped the hospital conditions we live in. The Moon stabilised the tilt of the Earth’s axis, which is responsible for maintaining a stable climate. The Moon also drives tidal forces shaping marine ecosystems and early life in the oceans.

Although many aspects of lunar formation are still being explored, the Moon remains a vital part of Earth’s history and evolution. Its presence has influenced our planet’s stability, climate, and even the development of life itself. Future space missions and advanced research may uncover more details about its origin, offering deeper insights into the early days of the solar system and the events that shaped the world as we know it.