A groundbreaking study suggests the moon, our closest celestial neighbor, might be over 100 million years older than previously thought.
Recent research has prompted scientists to reconsider the age of the moon, suggesting it might be older than earlier measurements indicated. This insight stems from the discovery that lunar rocks, previously thought to crystallize 4.35 billion years ago, may not accurately reflect the moon’s birth. The new hypothesis indicates that intense volcanic activity might have reset the age of these rocks 4.35 billion years ago, masking the moon’s actual age.
The evidence for an older moon primarily comes from rare lunar zircon minerals, suggesting a formation age of about 4.5 billion years, and simulations of planetary formation that argue against a late formation of the moon. The moon’s age has traditionally been deduced by analyzing samples collected during the Apollo missions, leading to the estimation that it is around 4.35 billion years old. However, the new data implies the moon formed approximately 80 million years after the solar system began, around 4.6 billion years ago.
The tectonic forces believed to contribute to this volcanic activity are similar to the tidal interactions seen today between Earth and the moon. When the moon first formed, it was in a closer orbit to Earth, experiencing more substantial tidal effects. These forces might have caused the moon’s surface to remelt, effectively giving it a volcanic facelift that distorted age measurements by erasing evidence of earlier impacts.
Giant cosmic impacts were once common in the solar system’s early days, yet most of them merged into larger celestial bodies about 4.4 billion years ago. This pattern suggests that a massive collision, such as the one suspected to have formed the moon, would have been improbable after the initial 250 million years of the solar system.
The researchers propose that the volcanic activity responsible for the moon’s remelting is akin to the turbulence observed on Jupiter’s moon Io, which is renowned for its volcanic dynamism due to similar tidal forces.
As scientists strive to confirm these findings, they look towards future lunar missions, such as China’s Chang’e 6 mission, expecting to acquire new lunar samples that may offer more definitive evidence regarding the moon’s age.
Francis Nimmo, the lead author, pinpoints the study’s aim as not only proposing an older age of the moon but also reconciling contrasting hypotheses about its formation. He notes that ‘dynamicists favor an older moon while geochemists lean towards a younger one.’ This research potentially satisfies both scientific perspectives by suggesting the moon underwent significant geological changes after its initial formation.
The latest findings about the moon’s age represent a pivotal chapter in unraveling the mysteries of our solar system. This research offers a fascinating perspective that bridges differing scientific views on lunar formation and provides a foundation for future exploration.
Source: Space
