New study reveals Moon's actual age, saying it is 100 million years older than previously thought

(Representative Image: Canva)

A recent study suggests the moon’s age may be older. Published in Nature, it proposes an earlier formation timeline. Scientists now believe the moon formed 4.51 billion years ago. This is over 100 million years earlier than previous estimates.

For decades, experts estimated the moon formed 4.35 billion years ago. This theory followed a Mars-sized object colliding with early Earth. However, the new research points to a later "re-melting" event. This event, caused by Earth’s gravity, reset lunar rock clocks.

Lead researcher Francis Nimmo from the University of California explained this. He said the moon rocks record the re-melting, not the formation. "The rocks don’t reveal when the moon was born," Nimmo stated.

The moon’s age has been debated for decades by scientists. Apollo samples suggested a younger moon, sparking conflicting theories. Some argued large collisions weren’t likely 4.35 billion years ago. Nimmo’s findings favour an older timeline for the moon's birth.

Lunar minerals like zircon also support this theory. Once thought to form at the moon’s creation, they’re much older. These minerals, dating back 4.5 billion years, puzzled researchers. Nimmo’s team links this to tidal heating from Earth’s gravitational pull.

The study compares lunar heating to Jupiter’s moon Io. Io’s interior heats from constant gravitational stress from Jupiter. Similarly, Earth’s gravity stretched and heated the moon's orbit.

Future lunar missions could reveal more about the moon's past. China's Chang'e 6 and NASA's Artemis programs are key efforts. Scientists hope they will refine the timeline of the moon’s formation.

Carsten Munker, from the University of Cologne, praised the study. He noted it helps bridge differing views on the moon’s age. "Understanding these events is key to solar system formation," Munker said.

The difference between 4.35 and 4.51 billion years is small. Yet it offers insights into the chaotic early solar system. Researchers believe pinpointing these events is vital for understanding our cosmic origins.