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Author Topic: what is the solution to the problem of isotopic anomalies in meteorites?  (Read 1342 times)

Offline Krupin

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       According to the author of this topic  the most difficult problem is the anomaly "neon-EĽ. This fraction of noble gas neon was discovered by Black and Pepin. The essence of the phenomenon is as follows: some substances of some meteorites contain nearly pure isotope neon-22, the usual content of which is 10%.
       This gives the following explanation. When the material is expanding supernova shell sufficiently cooled, solid minerals begin condensate . In some of them a radioactive isotope sodium-22 is  built. The radioactive decay of sodium-22 is formed neon-22, which remains a captive of the crystal lattice. These mineral grains with walled neon-22 incorporated then into the meteorites. There they were reveal.
       Isotopic anomalies in meteorites known for several decades. However, they remain a mystery to scientists. Clearly, "queer" isotopes were synthesized in the depths of the stars. Shortly before the birth of the planets of the solar system, they were removed from there supernova explosions.
       At first glance, the situation is simple. Supernova exploded near the gas-dust cloud. Synthetic isotopes were injected into the cloud and became part of the meteorites. Furthermore explosion squeezed cloud and initiated the formation of stars with planets.
      However, such a simple scheme stumbles on a series of simple questions.

      In order to inject a sufficient amount of substance supernova to explode relatively close to the cloud. But then the explosion will dispel the cloud, but not compress it.
       Supernova shell moves at a speed of 1000-10 000 km / sec. During impact of a cloud of cosmic dust particles, formed in the substance of the shell should evaporate. Accordingly, will be destroyed all  isotopic anomalies which are contained in them.
How to solve this puzzle.


 

Offline Krupin

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But the half-life of sodium-22 is only 2.67 years. Therefore, minerals, which are carriers of sodium-22 must be synthesized a few years after the supernova explosion. Otherwise, all the sodium-22 will turn into neon-22 before the start of synthesis.

When the expanding supernova shell reaches the boundary of dust and gas cloud, cosmic dust particles  contain already no sodium-22, but neon-22. These dust particles fly into a cloud at high speed. Despite this dusts should not evaporate. They should not even warm up too high, otherwise all neon-22 will run away from the crystals.
 

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