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The first findings of NASA's Genesis probe have just been published in the "Proceedings of the National Academy of Sciences", and the results are surprising.
The mission involved the launch of a probe (in 2001) that was sent to a point 1.6 million km from the Earth, well beyond the influence of the terrestrial magnetic field, to collect solar wind particles. The mission was to end in 2004 with the return of the probe to Earth with a parachute. Unfortunately the parachute failed and the probe crashed to Earth, rather like a meteorite (see photo)!
Fortunately, the precious cargo was not lost, and laboratory studies were initiated on the material collected.
From these studies some extraordinary conclusions have been reached regarding the isotopic ratios of some elements in the solar wind, compared to those on our planet.
As we know (?), the solar system was born from a single cloud of gas and dust, and so it is natural to assume that the various isotopes in the Sun and in the planets (Earth included) should be present in the same ratios.
An element is defined by the number of protons in its nucleus, but for any given number of protons the number of neutrons can vary, changing the nuclear mass, and these variations are different isotopes. If, in the Sun, the ratio of light oxygen to heavy oxygen has a certain value, then it was expected that this same value would be present in the Earth. This is not so however.
Analysis of the particles gathered by Genesis indicates that there are significant differences, specifically, the Earth has fractionally more heavy oxygen than the solar wind. The same is seen for other elements and this disagrees with current theories.
Given that there is no reason to think that the solar wind would have a composition different from that of the Sun, the isotopic ratio discrepancies are a mystery. There is something missing from our understanding of either how the Earth formed or how the Sun processes the various elements.
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