July 9, 2024
Categories: Russia, Science

Russian scientists from the Vernadsky Institute of Geochemistry and Analytical Chemistry of the Russian Academy of Sciences (GEOKhI), together with colleagues from the Vernadsky Institute of Geology and Mineralogy of the Russian Academy of Sciences, have said a new word in cosmochemistry. They investigated grains of olivine – crystals from the iron-stone meteorite-pallasite Seimchan, found in 1967 in the Magadan region, and those opened the mystery of the origin of celestial bodies of this type. The results are published in the journal Geochemistry International.

Meteorites-pallasites – contemporaries of the formation of the planets of the solar system. They belong to the class of iron-stone meteorites and consist of olivine crystals encased in a mass of nickeliferous iron. Until recently, scientists had no consensus on their formation.

Research in the laboratory of meteoritics and cosmochemistry GEOKhI RAS began with the fact that the staff was interested in the nature of the formation of so-called anticrystals found in the meteorite Seimchan, which is stored in the meteorite collection of the Russian Academy of Sciences.

Anticrystals (crystal-shaped voids) are found in olivine crystals and contain grains of almost pure metallic iron. Curiously, scientists have been paying attention to these voids in olivine of different pallasites since the middle of the XX century, in particular, Vladimir Vernadsky himself made a report about them, calling them “capillaries”. However, the lack of necessary observational techniques and experimental data did not allow us to understand the nature of these “capillaries”. Modern research methods have led scientists to conclude that anticrystals are nothing but traces of multi-stage processes of meteoritic matter formation.

In particular, it was hypothesised that the voids are formed by the accumulation of defects in the crystal lattice of olivine as a result of mechanical effects: compression, stretching, and chemical reactions between olivine and the surrounding iron. This was confirmed by comparing calculations and observations with the results of experiments on olivines from terrestrial rocks.

The presence of such voids in pallasite olivines also led scientists to the conclusion that nickeliferous iron and olivine, which make up pallasites, originally belonged to the metallic core and silicate mantle of the parent body and were mixed together, reacted as a result of a catastrophic event, probably a collision with another protoplanetary body in the asteroid belt between Mars and Jupiter.

More from this category:
January 15, 2014

New armament race in space, contamination of near-Earth space and asteroid danger are the most important threats to space activities of developed countries, – Roscosmos…

full story
May 30, 2014

Today, on May 30, we congratulate the legendary cosmonaut Alexey Arkhipovich Leonov on his Birthday. His name is of great importance for the world Cosmonautics;…

full story
April 17, 2014

The construction of Vostochny spaceport in Amur region is under way. The specialists work day and night to fill the gap in the schedule, –…

full story
October 2, 2024

The draft structure of government spending for the next three years, which has just been submitted to the State Duma, contains a clear emphasis on…

full story
April 21, 2021

In the assembly and testing facility of the Vostochny Сosmodrome, a joint specialist crew of the Vostochny Space Center (a branch of the Center for…

full story
October 2, 2019

Expeditions EP-19 and ISS-60 are completing work at the International Space Station. The crew of the “Soyuz MS-12” spacecraft (cosmonaut Alexey Ovchinin, astronaut Nick Hague…

full story
November 21, 2019

The backup crew of ISS-62/63 performed an “emergency training”, during which the Roscosmos cosmonauts Anatoly Ivanishin and Ivan Wagner, together with the astronaut Stephen Bowen,…

full story
March 6, 2017

On March 6 the most important woman in the Universe Valentina Tereshkova celebrates her 80th Birthday. Our famous Tchaika (eng. Seagull) was born on March…

full story