Inspired by the current state of Jupiter’s satellite Io, the researchers were able to combine the data. A priority Contradictions on the age of the moon. For many years, scientists have faced a dilemma: How can we make sense of the 160 million years that separate the formation of the Moon from the rocks of its crust?
We know that the Moon was formed after the Titanic collided between Earth and another Mars-sized planet, called Theia. Shaking the Earth’s surface, the catastrophe ejected a huge mass of rock, which quickly became our satellite. But when did this major event in Earth’s history take place?
Although we know that this happened very quickly after the formation of the Earth, scientists still have difficulty proposing a precise date. And for good reason: While we thought lunar samples were brought back by various missions since then. Apollo 11Apollo 11 While dating the moon’s rocks will help clarify the moon’s age, the contrast has blurred the lines. These rocks are actually only 4.35 billion years old, contradicting models based on the dating of a few zircon grains that suggest the Moon formed 4.51 billion years ago. And 160 million years of uncertainty is still nothing!
Age of the Moon: Relying on Zircon
For researchers at the University of California Santa Cruz, it DisagreementDisagreement The age may actually be linked to a more complex geological history of the Moon than previously thought. In an article published by the journal The naturethey present a view that makes it possible to combine these different data. A priority Contradictory
The authors thus suggest that the few zircons found in lunar samples clearly indicate the age of the moon. Zircons are small. MineralsMinerals of which resistanceresistance Extreme allows them to pass through time without being changed or modified. Thus they are able to retain the chemical signature directly acquired at the time of their formation. On Earth, tectonic forces and erosion constantly rework the rocks and minerals that make them up. A necessary process in terrestrial dynamics, but one that represents quite a thorn in the side for scientists, as it means that the original chemical signal is almost always erased. Except for zircon, which turns out to be the only direct witness to Earth’s earliest days… and the moon.
Dating of zircons in lunar rocks has made it possible to say that the Moon formed between 4.51 and 4.43 billion years ago. But how can we explain the age of these rocks, which are 80 to 160 million years younger, than the rocks they belong to? Well, just as easy as the same process of erasing the initial data.
4.35 billion years ago, a moon very similar to Io?
For researchers, The crystThe cryst The Moon’s surface may indeed have experienced a second episode of total fusion around 4.35 billion years ago. By melting, the rocks would have lost their initial chemical signal acquired during the crystallization of the ocean. MagmaMagma Ancient, to acquire a new one, denoting a younger age. Only zircons would have emerged from this extreme event. VolcanoVolcano The surface of the moon appears to have been completely altered.
Today, the celestial body experiencing the most volcanic activity in our solar system is Io, Jupiter’s moon. This activity is fueled by the powerful Sea forcesSea forces Encouraged by his proximity to The gas giantThe gas giant. To explain this massive volcanic event 4.35 billion years ago, scientists believe that a cause and effect relationship can also be applied to the Moon.
At this time, the moon is actually located at one. orbitorbit Very close to the ground. The distance between the Earth and the Moon was then about one-third of the current distance. Also, the orbit has become highly elliptical. A relatively similar situation Come onCome on Currently
The Moon would therefore have been subject to strong tidal forces that would have “heated” its interior, causing Partial integrationPartial integration are of coatcoat and triggering a phase of intense volcanism that would have reworked its entire surface.
