Some cosmologists suspected that Earth and Mars were formed by the accumulation of large amounts of matter from the regions where the giant planets were born. By showing that this shouldn’t be the case, other cosmologists discovered that these two planets had accumulated material from a vanished collection of celestial bodies that left no direct trace in the form of meteors in the belt, the main asteroids.
The term cosmic chemistry is generally attributed to Harold Urey. the Nobel Prize in Chemistry, master in the past Quantum theory of atoms and molecules, as shown by one of his works published in 1930, he turned in the early fifties in the direction of an origin theory the moon And more generally from the planets solar system in one The book was published in 1952 We can rightly regard it as one of the starting points in cosmological chemistry, however the point at which the term was introduced.
In the following years, Uri and his colleagues conducted a very extensive analysis of the time of abundance chemical elements, in particular non-volatile, in meteoritesBy making comparisons with other literatureambiance the Soleil and rocks on Earth, and in order to derive a possible determination of the abundance of chemical elements on a cosmic scale.
The article he would publish on this subject in 1956 with Hans Eduard Suess (grandson of Geologist Austrian Eduard Suess) is one of the bases Huge article published in 1957 via I Margaret Burbage, G.R. Burbidge, William A. Fowler, and F. Hoyle. This foundational work explained for the first time how stars It can make chemical elements heavier thanhydrogen, Even Act And beyond the theory of stellar nuclear structure.
The solar system is a laboratory for studying the formation of giant planets and the origin of life that can be used with the rest of the universe, and can be observed for the same purpose. mojo: Modeling the origin of the Jovian planets, This means that modeling the origin of the Jovian planets, is a research project that has led to a series of videos presenting the theory of the origin of the solar system and in particular the gas giants by two famous specialists, Alessandro Morbidelli and Shaun Raymond. For a fairly accurate French translation, click the white rectangle at the bottom right. The English translation should then appear. Then click on the nut to the right of the rectangle, then click on “Subtitles” and finally on “Translate automatically”. Choose “French”. © Lawrence Honorat
Cosmic chemistry, the key to the origin of the solar system
Over the next decades, cosmic chemistry will unite with analytical models and Digital On the formation of planets resulting from celestial mechanics and the kinetic theory of Gas Under the theoryaccumulation It was initially developed by researchers such as Russian Victor Safronov and the United States George Weather. This resulted in a solar system planet formation scenario that is widely accepted today, further supported by observations of planetary systems emerging in formation. A good presentation is given in the video above and is part of a series on the topic. There is also an excellent book about Physics and chemistry of the solar system We can consult with her.
However, this scenario breaks down into several possible sub-scenarios depending on whether one seeks to understand, for example, the origin of rocky planets or gas giants, so there is still work to be done to understand how planets form. As new data becomes available, the pendulum swings between these sub-scenarios as they become more accurate. We see a new example today with a magazine post” science progress “Work we owe to researchers from the University of Münster (Germany) and the Côte d’Azur Observatory (France), California Institute of Technology (United States of America), Natural History Museum Berlin (Germany) and the Free University of Berlin (Germany). It is based on a new and more accurate determination of the composition of the rocky planets of Earth and Mars.
In a statement, cosmic chemist Christoph Burckhardt of the University of Münster, first author of the study, explained the research team’s initial goal: We wanted to know if the building blocks of Earth and Mars come from the outer or inner solar system. This requires them to obtain an abundance determination of isotopes From metal Rare in the rich outer layers silicate Which planets are Titanium, the Zirconium and the molybdenum By examining them as never before in Martian meteorites in particular.
The cosmological model of the formation of the solar system includes a regression chemical and temperature in protoplanetary disk Rich in gases and dust as the planets formed from the cooling of this Theme that processcollapse attraction clouds The dusty particle that gave birth to the proto-Sun is surrounded by this disk. Closestar Central, it’s rather rocky bodies heat resistant material It contains a few volatile elements that are condensed, such as silicates and minerals.
Behind a line called ice or snow, it is dust surrounded by Coat Ice, mainly water, which will condense, with comets and carbonaceous meteorites such as the famous Chondrite Dalind. So in the inner part of the protoplanetary disk were born the rocky planets and in the outer part the gas giant planets were born. Jupiter And Saturnand ice giants Neptune And Uranus.
The chemical gradient is found at the abundance level of certain isotopes, so that it can be used as tracers to assess the chemical reservoir at a certain distance from the Sun Material A meteorite is formed, which is itself sometimes a fragment produced during the impact of a large object such as a fetus A planet or minor planet (see details on these terms in the video above).
However, there are signs of a turbulent mixing process in the protoplanetary disk and other processes that indicate that material was exchanged between the inner and outer parts of this disk. It is the existence and significance of these material transfers that are often discussed by specialists today. Not so long ago, one of the studies advanced the thesis that there is a break between these two parts of the disk, which leads to the blocking of chemical transport processes.
The work of Christoph Burckhardt and colleagues appears to be consistent because it leads to the recognition that Earth and Mars were formed primarily from the inner material of the Solar System and that only a small percentage of the constituent elements of these two planets would originate from “beyond”. the’orbiting Jupiter, in good agreement with a scenario already presented by George Weatherel.
Remember, we have good reasons to believe that the majority of meteorites we find on Earth come from asteroid belt Main between Mars and Jupiter. This same belt has been filled throughout the history of the solar system by small celestial bodies from both the inner solar system and the outer part of it, in particular due to the influence of Jupiter’s gravity. The non-carbonaceous chondrites reflect the composition of the outer protoplanetary disk outside Jupiter and the non-carbonaceous chondrites in the interior below.
Meteorites whose memory is not preserved in the main asteroid belt
It is possible to model the distribution of abundances of titanium, zirconium, and molybdenum isotopes in the protoplanetary disk as well as the way in which matter accumulates to form rocky planets and thus returns to the origin of matter in the beltasteroids A person who consists of Shell Mars and Earth. These models were combined with data from new measurements of these isotopes in the Martian rocks, and the state of the Earth is already known.
Cosmologists then discovered that the outer rocky layers of Earth and Mars have little in common with the carbonaceous chondrites of the outer Solar System at the level of newly identified isotopes, which can only be explained if these planets formed. by largely isolating them from material inputs in the form of carbonaceous chondrite co-materials, as opposed to a scenario involving significant accumulation of “gravel” (pebbles In English, as shown in the diagram below and Shaun Raymond’s explanations in the video above) formed in the outer portion of the protoplanetary disk.
The second isotopic discovery is that the composition of Mars and Earth is also not understood by limiting itself to chemical deposits of known carbonate and non-carbonate chondrites. On the other hand, it can be well explained from a third reservoir described by modeling the chemical gradient in the protoplanetary disk, a reservoir corresponding to the deeper region. Small rocky bodies in this part were not found in the main asteroid belt, but part of them seems to have accumulated on Earth and Mars.
We can believe it is the same for Venus And Mercure Even if these discoveries do not disturb the classic scenario of formation terrestrial planets From the collisions of rocky planet embryos described in the previous video by Sean Raymond.
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