The ratio of krypton isotopes in the Martian meteorite indicates different ways of origin of volatile substances in its depths and atmosphere. This forces us to consider the model of the formation of the planet.
Martian meteorite containing volatile substances
Scientists studying the Martian Chassigny meteorite have made an unexpected conclusion about the past of the red planet. Unlike most other similar stones, this fragment, which fell in France in 1815, is considered part of not surface, but deep rocks. In particular, scientists were interested in the isotopes of krypton contained in it.
By the ratio of these isotopes, it can be concluded about the origin of volatile substances, such as gases, water and some metals contained in the sample. The traditional theory of the origin of the planets says that there were two sources of these parts.
The first is a protoplanetary cloud. Volatile substances from it settled on the planet during its formation. They dissolved in the magma ocean, which then represented the surfaces of celestial bodies and then degassed from them, forming the atmosphere.
Later, a second source was connected. They were chondrites from meteorites that crashed into the surface of the planet. At the same time, it is believed that deep rocks should contain the most ancient isotopes that have not been exposed to later influences.
The depths of Mars and its atmosphere
There are very few isotopes of krypton in the Chassigny meteorite. But when a new technique was applied to them, it turned out that the picture corresponds exactly to the chondritic origin of volatile substances in it. This is very strange, considering that the atmosphere of Mars is formed by those substances that got to the planet directly from the protoplanetary cloud. For more information, see the article published in Science.
How this could happen, scientists cannot explain exactly. It can only be unequivocally stated that the fall of meteorites on Mars began much earlier than is believed. Chondrites fell on it when the protoplanetary cloud around did not have time to disperse.
Even more, calculations show that the atmosphere of Mars simply could not have been formed by degassing its igneous rocks. It seems that the red planet captured it from the protoplanetary cloud after the fiery ocean solidified.
All this is quite contrary to what people know about the formation of planets in the Solar system. In particular, Mars should have cooled down very quickly immediately after formation. In addition, it remains unclear why this primary atmosphere was not “swollen” by solar radiation.
According to phys.org
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