60Fe anomaly in a deep-sea manganese crust and implications for a nearby supernova source.
نویسندگان
چکیده
A nearby supernova (SN) explosion in the past can be confirmed by the detection of radioisotopes on Earth that were produced and ejected by the SN. We have now measured a well resolved time profile of the 60Fe concentration in a deep-sea ferromanganese crust and found a highly significant increase 2.8 Myr ago. The amount of 60Fe is compatible with the deposition of ejecta from a SN at a distance of a few 10 pc. The well defined time of the SN explosion makes it possible to search for plausible correlations with other events in Earth's history.
منابع مشابه
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ورودعنوان ژورنال:
- Physical review letters
دوره 93 17 شماره
صفحات -
تاریخ انتشار 2004