On Earth, discovered radioactive debris of supernova stars

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    An international team of scientists found evidence that several supernova explosions occurred relatively recently from our planet in the recent space standards. Scientists have discovered "debris" of stars that have settled on Earth, in particular the iron isotope - iron-60.

    The iron-60 isotope was found both in sedimentary rocks and in samples of the earth's crust taken in the Pacific, Atlantic and Indian oceans. It accumulated in these places from 3.2 to 1.7 million years ago.

    “We were surprised at how the wreckage was clearly distributed over 1.5 million years,” says Dr. Anton Wallner, a nuclear physicist at the School of Physics and Engineering at Australian State University (ASU). - This suggests that the supernova exploded one after another, and there was a whole series of them. It is interesting how this coincided with the period when the Earth cooled and changed from the Pliocene to the Pleistocene. ”

    Also, isotopes were found related to a supernova explosion of the order of eight million years ago, coinciding in time with global changes in the fauna in the Miocene. Scientists believe that supernova explosions occurred at a distance of about 300 light years - in a fairly old star cluster, the distance to which has increased since then. There are almost no stars left in it, which means that most of them have already exploded.

    The brightness of these phenomena on Earth should have been comparable in brightness with the moon. True, cosmic radiation even in this case would be too weak to directly affect the fauna of the planet. Some scientists believe that an increase in cosmic radiation could affect the cloudiness of the planet.

    Iron-60 - a radioactive isotope of ironwith a half-life of 2.6 million years. This is one of the heavy elements that form in stars and propagate after their explosion. Since it reaches the Earth in extremely small quantities, scientists needed very precise techniques to detect this isotope in the rock. In the study, scientists examined 120 samples from different parts of the oceans, while fences covered the last 11 million years of the planet’s existence. Scientists from Australia, Austria, Israel, Japan, Germany participated

    in the work .

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