Scientists find increase in asteroid impacts on ancient Earth by studying the Moon

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A team of scientists has determined the number of asteroid impacts on the Moon and Earth increased by two to three times starting around 290 million years ago. Previous theories held that there were fewer craters on both objects dating back to before that time because they had disappeared due to erosion. The new findings claim that there were simply fewer asteroid impacts during that earlier period.
via Science Daily
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Saturn hasn't always had rings

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In its last days, the Cassini spacecraft looped between Saturn and its rings so that Earth-based radio telescopes could track the gravitational tug of each. Scientists have now used these measurements to determine the mass of the rings and estimate its age, which is young: 10-100 million years. This supports the hypothesis that the rings are rubble from a comet or Kuiper Belt object captured late in Saturn's history.
via Science Daily
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