Moon's Authentic Age Unveiled Through Apollo Crystals
Moon's Authentic Age Unveiled Through Apollo Crystals
The Moon, our planet's steadfast companion in space, has been circling Earth for a staggering 4.5 billion years, almost as long as Earth itself has existed. However, recent investigations into crystals from the Moon's surface suggest that our lunar companion might be even older than previously assumed.
Initially, scientists believed the Moon formed when a Mars-sized protoplanet collided with early Earth, an event that occurred approximately 4.35 billion years ago, based on evidence found on the Moon's surface. Determining the Moon's growth timeline isn't just beneficial for understanding the Moon's past; it also aids planetary scientists in deciphering the evolution of our planet and the wider solar system.
A new study now puts forward the idea that while the Moon's age is estimated to range between 4.35 and 4.51 billion years, the younger age might indicate a unique remelting incident distinct from the Moon's "initial crystallization of the lunar magma ocean." They published this finding in Nature today.
The plethora of 4.35 billion-year-old rocks on the surface led the researchers to speculate about a widespread remelting incident, implying a slightly older Moon age. They derived this older age from zircon crystals recovered from the lunar surface by Apollo missions. Contrary to the rest of the lunar surface, many of these near-surface crystals survived the remelting, preserving a more accurate record of the Moon's age.
The researchers also clarified that the Moon can't be older than 4.53 billion years old, the earliest possible moment core formation could have ceased. The Moon might have formed approximately 180 million years prior to the heating event that affected the satellite. So, while the lunar surface we're familiar with is primarily a result of a remelting event, and the Moon's age might be older than previously believed, it's not radically so.
The paper reports that current models can't substantiate the hypothesis of impacts causing the resetting event. However, the exact cause of the widespread lunar surface melting remains a topic of debate among researchers, who propose that it might have been driven by the Moon's orbital evolution. In simpler terms, the stress exerted by Earth and Sun's gravitational pull on the Moon may have initiated this widespread remelting.
Earlier this year, a study published in Nature Geoscience suggested that the Moon underwent a drastic upheaval, rotating itself inside out just a few million years into its formation. This latest study adds another layer of complexity to the Moon's origin story.
Space exploration still has a long way to go, and initiatives like the Artemis program—which aims to return humans to the Moon for the first time in decades—will play a crucial role in unveiling the origins of our lunar companion.
In the future, understanding the Moon's age could provide valuable insights into the evolution of our solar system's planets. Advanced science and technology, including space missions and mineral analyses, will be crucial for further unraveling the Moon's complex history.
As our reliance on technology and science grows in the future, so does the potential for groundbreaking discoveries about the Moon, such as the possible existence of forgotten celestial events or the existence of resources that could aid in space colonization.