Four and a half billion years ago, the solar system was still chaotic. The earth was still growing
In principle, most scientists agree on how the moon was formed, but not about the details of the process, and especially not about the time when it occurred.
The latest planetary simulation resultsGeophysicists at the German Aerospace Center (Deutsches Zentrum für Luft- und Raumfahrt; DLR), led by Maxim Moris, together with researchers from the University of Münster, suggest that protoplanet collided with the young Earth about 140 million years after the birth of the solar system 4,567 billion years ago . According to their calculations, this happened 4.425 billion years ago.
В то время Земля только что превратилась в the planet. During this development, heavy metal components drowned toward the center of the earth and formed a core of iron and nickel, which was surrounded by a thick mantle of silicate rocks. Mantle rocks are getting hotter. This allowed the separation of metals and silicates in the bowels of the Earth for several tens of millions of years.
At this stage, the Earth was hit by Tei,protoplanet that was the size of Mars. In the early days of the solar system, there would be many such bodies. Some were thrown out of the solar system, while others were destroyed as a result of collisions with other bodies. Thea, however, hit the Earth and ejected so much material from the mantle of the planet that the moon could form from it. During this strong blow, an igneous ocean was formed with a depth of several thousand kilometers. Today, after this clash, there are no traces of Thei left.
The collision of two bodies with its enormous energyalso evaporated a large number of stones from the early mantle of the Earth. All this substance was thrown away and collected in a dust ring around the Earth before it gathered again to form into stone. Based on this, the moon formed in a short time, possibly in just a few thousand years.
Scientists largely agree with the history of educationThe moon. However, they could not establish the exact date, since not one of the lunar rocks delivered to the Earth records the age of the Earth’s natural satellite. Researchers from DLR and the University of Münster determined when the moon formed using a new indirect method. Their calculations show that this most likely happened at the very end of the formation of the Earth.
One of the oldest moon rocks. Provided by: NASA / AO / AAKO
Not only did the Earth have an ocean of magma in the earlyage. The energy obtained as a result of accretion also led to the formation of an igneous ocean on the moon. The moon almost completely melted and, like the Earth, was covered by an igneous ocean with a depth of more than 1000 kilometers. This magmatic ocean quickly began to solidify and formed a crust of floating light crystals on the surface. But beneath this insulating crust, which slowed down further cooling and solidification of the magmatic ocean, the moon remained molten for a long time. Until now, scientists have not been able to determine how long it took for the magma ocean to crystallize completely, so they could not conclude when the moon originally formed.
Ocean of magma and the first rocky crust on the moon. Courtesy: NASA / Goddard Space Flight Center.
To calculate the lifetime of an igneousOcean of the Moon, scientists used a new computer model, which for the first time comprehensively examined the processes associated with solidification of magma. The model results show that the magmatic ocean of the moon was long-lived, and it took almost 200 million years to fully solidify in mantle rocks. Older models showed a solidification period of only 35 million years.
To determine the age of the moon, scientists had togo even further. They calculated how the composition of minerals rich in magnesium and iron, which are formed during the hardening of the magmatic ocean, changed over time. The researchers found a sharp change in the composition of the remaining magmatic ocean as it solidified.
This discovery is significant because itallowed the authors to connect the formation of various types of rocks on the moon with a certain stage in the evolution of its magmatic ocean. Comparing the measured composition of lunar rocks with the predicted composition of the magmatic ocean from the model, the researchers were able to trace the evolution of the ocean to its starting point, the time when the moon formed.
Study results show that the moonformed 4.425 ± 0.025 billion years ago. The exact age of the moon is in agreement with the age previously determined for the formation of the Earth’s metal core using the uranium-lead method, the point at which the formation of the planet Earth was completed. For the first time, the age of the moon can be directly related to the event that occurred at the very end of the Earth’s formation, namely, the formation of the core.
Read also
Comet NEOWISE is visible in Russia. Where to see her, where to look and how to take a photo
New thin solar panels can be attached to any surface
Australia will start paying for the use of electric vehicles