Central Idea
- For years, the moon’s age was believed to be around 4.42 billion years, but recent research challenges this notion.
- A study has used advanced technology called atom probe tomography (APT) to evaluate lunar sample 72255, which contained 4.2 billion-year-old zircon crystals.
Unveiling the Moon’s True Age
- Zircon’s Significance: Zircon is not only the oldest mineral on Earth but also holds crucial information about the formation of our planet.
- Lead Clustering Analysis: Using nanoscale spatial resolution, the scientists analyzed the clustering of lead within the samples, a common method to estimate the age of zircon in rocks.
- Revised Age: The study concludes that the moon likely formed approximately 4.46 billion years ago, within the first 110 million years of the solar system’s existence.
- Comparing Earth’s Age: Earth is estimated to be between 4.5 and 4.6 billion years old, making the moon slightly younger at approximately 4.46 billion years old.
Implications of Zircon and Lunar Formation
- Giant Impact Hypothesis: The researchers propose the giant impact hypothesis, suggesting that a celestial body named Theia, possibly Mars-sized, collided with Earth during its formation. This collision ejected debris, which coalesced to form the moon.
- Lunar Magma Ocean: This collision led to the formation of the Lunar Magma Ocean, influencing the moon’s interior composition.
- Preserved Zircon: Subsequent lunar surface bombardments reworked the earliest crust, leaving some zircon crystals modified and others preserved. Identifying these preserved zircon crystals provided insights into the moon’s age.
