According to researchers from the University of California, Los Angeles, our Earth’s natural satellite is at least 4.51 billion years old, meaning that it’s in fact hundreds of millions of years older than previous studies suggested. In fact, the moon is only around 30 million years younger than Earth.
According to a press release on UCLA’s website, scientists based their discovery on the analysis of minerals from the moon called ‘zircons,’ brought back to Earth by NASA’s Apollo 14 mission which took place in 1971.
“Zircons are nature’s best clocks,” said Kevin McKeegan, a UCLA professor of geochemistry and cosmochemistry, and a co-author of the study. “They are the best mineral in preserving the geological history and revealing where they originated.”
In order to obtain the new age of the moon, scientists utilized mass spectrometry techniques to study samples of eight zircon grains and then compared spectrometric data to the figures attributed to the time our solar system was born.
The results were mind-bending. As it turns out, our Moon formed only about 60 million years after our solar system came into existence, while previous studies suggested that it happened 100 or 200 million years after the solar system’s formation.
Previous studies concluded the moon’s age based on moon rocks that had been contaminated by multiple meteorite collisions. McKeegan said those rocks indicated the date of some other events, but not the age of the moon.
In an unrelated study, researchers from the Weizmann Institute of Science in Israel suggest our Moon may have formed from a SERIES of massive impacts, and not just ONE.
The newly proposed theory indicates that approximately 20 moonlets would eventually coalesce to form the Moon we see today.
Previously, researchers believed the moon formed after Earth was hit by a planet the size of Mars, billions of years ago, and it’s called the giant impact hypothesis. The hypothesis states that our moon formed from leftover debris following an indirect collision between our planet and an astronomical body called ‘Theia’ approximately 4.5 billion years ago.
A study published in the journal Nature Geoscience, explains why Earth’s natural satellite is mostly made from Earth-like materials, and not a mixture of elements and those from another celestial body that participated in the collision.
Furthermore, this implies that the moon was formed over a period of several million years, and its interior may even hold evidence of that period of a cosmic bombing. This means that the Earth and Moon’s interiors are also less mixed up, and may have records of the events that eventually gave birth to both the Earth and the moon.