The Moon is 40 million years older than previously thought
By analyzing tiny lunar crystals gathered by Apollo 17 astronauts in 1972, a groundbreaking study led by researchers at the Field Museum and the University of Glasgow has recalculated the age of the Earth’s Moon. While earlier estimates pegged the Moon’s age at 4.425 billion years, this new research suggests it is actually 4.46 billion years old, making it 40 million years older than previously believed.
The study, which was published in the journal Geochemical Perspectives Letters, utilized Northwestern University’s state-of-the-art atom-probe tomography facility to determine the age of the oldest crystal in the sample. These zircon crystals, hidden within lunar dust, provided crucial insights into the timeline of the Moon’s formation.
Northwestern’s Dieter Isheim, a co-author of the study, emphasized the technological advancements that have been made since the last manned Moon mission in 1972. He stated, “These samples were brought to Earth half-a-century ago, but only today do we have the necessary tools to perform microanalysis at the requisite level, including atom-probe tomography.”
The research delves deep into the process of radiometric dating, likening it to an hourglass where the transformation of atoms indicates the passage of time. By analyzing the proportion of uranium and lead atoms in the zircon crystals, the researchers could determine the age of the sample.
A significant event in the Moon’s history is its formation, which occurred when a Mars-sized object collided with the Earth over 4 billion years ago. This colossal impact resulted in a chunk breaking off from Earth, eventually forming the Moon. The energy from this impact melted the rock that later solidified to become the Moon’s surface. The zircon crystals, which couldn’t have survived in a molten state, are evidence of the Moon’s age post this cooling period.
The study’s senior author, Philipp Heck, emphasized the Moon’s importance in our planetary system, stating, “Without the Moon, life on Earth would look different. It’s a part of our natural system that we want to better understand, and our study provides a tiny puzzle piece in that whole picture.”
Reference: Original Article