A recent study published in Nature has challenged the long-held estimate of the moon’s age, suggesting it could be up to 4.51 billion years old. Planetary scientists believe that the moon’s surface “remelted” around 4.35 billion years ago, masking much older lunar features beneath.
The current understanding of the moon’s formation dates back to a collision between Earth and a Mars-sized protoplanet, which is believed to have occurred approximately 4.35 billion years ago. Scientists estimated this date by dating moon rock samples, assuming they originated from the ancient magma ocean that existed after the impact.
However, researchers led by Professor Francis Nimmo of the University of California Santa Cruz propose an alternative explanation for the moon’s age. By studying thermal models and crater patterns on the moon, as well as the age of certain minerals, their research suggests that the moon may be older than previously thought.
According to this study, the moon went through a period of heating and cooling where its surface “remelted,” potentially erasing craters formed by asteroid impacts around 4 billion years ago. This could explain why there are fewer craters on the moon’s surface than expected.
If confirmed, this revised age would be approximately one and a half million years older than the current estimate of 4.35 billion years. The study also sheds light on ongoing efforts to explore the moon, particularly its south pole, where scientists believe water may exist.
Source: https://news.sky.com/story/moon-may-be-much-older-than-thought-because-of-remelting-surface-13275963