▲ Harrison Schmidt, astronaut of NASA’s Apollo 17, which landed on the moon for the last time in human history, collecting lunar dust and meteorites. Schmidt was the first scientist-turned-spaceman. This research team used the lunar samples brought by Schmidt to accurately reveal the moon’s age. Provided by the National Aeronautics and Space Administration (NASA) The Moon, the third planet in the solar system and the only satellite of Earth, has been an object of mystery since the birth of mankind. Since humans first set foot on the moon in 1969, the moon has gone from the realm of myth and legend to an object of science, but is still shrouded in secrets.
It is known that the moon was formed from the fragments that came out when a Mars-sized protoplanet collided with the Earth and was destroyed. For this reason, the exact age of the moon is still unknown. Scientists estimate the moon’s age in various ways, but they are inconsistent.
In this situation, as a result of a detailed analysis of meteorite crystals brought back from the moon by humans, research has shown that the moon is 40 million years older than previously thought.
A joint research team from the University of Glasgow, UK, University of California, Los Angeles (UCLA), Northwestern University, Chicago Fields Museum, and the University of Chicago analyzed crystals formed after the moon’s magma ocean cooled and found that the moon was formed at least 4.46 billion years ago. revealed. This is approximately 40 million years older than the known time of moon formation. The results of this study were published in the October 23 issue of Geochemical Perspectives Letters, an international academic journal in the field of geology.
The research team conducted a detailed analysis of lunar meteorites and dust samples brought back by the U.S. Apollo 17 during its final lunar exploration mission in 1972. We focused on zircon crystals formed after the magma ocean cooled. This is to examine the isotope ratio of uranium and lead in zircon crystals. ▲ A microscopic enlargement of a piece of zircon in a moon meteorite crystal. Provided by the University of Glasgow, UK To achieve this, the research team used atomic exploration tomography, which involves minutely evaporating crystal atoms using a focused ion beam microscope and then measuring the composition and age using a mass spectrometer. Although the moon’s age has been measured before, this study is the first to measure its age using atomic probe tomography.
As a result of analyzing the ratio of isotopes in zircon crystals, the crystal formation period was found to be approximately 4.46 billion years ago.
Professor Philip Heck of the University of Chicago, who led the research, said, “We expect that this study will make the dating of the moon more accurate.” He added, “As the moon is a hint that can provide answers to problems that have not yet been solved on Earth, this study will help us understand the history of the Earth.” “We will be able to know more accurately,” he said.
Reporter Yoo Yong-ha
