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Updated: Jun 29, 2026
09:45
Laboratory Simulation of an Iron(II)-rich Precambrian Marine Upwelling System to Explore the Growth of Photosynthetic Bacteria
Published on: July 24, 2016
Search for supernova-produced 60Fe in a marine sediment
C Fitoussi1, G M Raisbeck, K Knie
1Centre de Spectrométrie Nucléaire et de Spectrométrie de Masse (CSNSM) IN2P3/CNRS, Université Paris Sud, Bâtiment 108, Orsay, France.
Physical Review Letters
|October 15, 2008
Summary
Researchers found no evidence of a supernova
Area of Science:
- Cosmic rays
- Nuclear astrophysics
- Geochemistry
Background:
- A previous study suggested a nearby supernova around 2.8 million years ago based on iron-60 (60Fe) in deep-sea crusts.
- This interpretation implies a significant cosmic event impacting the solar system.
Purpose of the Study:
- To verify the supernova hypothesis with higher time resolution.
- To obtain a more precise estimate of the iron-60 (60Fe) flux from potential cosmic events.
Main Methods:
- Analysis of iron-60 (60Fe) concentrations in a precisely dated marine sediment core.
- Radiometric dating techniques to establish the sediment's timeline.
Main Results:
- No statistically significant iron-60 (60Fe) peak was detected in the marine sediment corresponding to the 1.7 to 3.2 million year ago timeframe.
- The measured 60Fe levels were lower than expected based on the supernova interpretation.
Conclusions:
- The findings do not support the previous interpretation of a nearby supernova event 2.8 million years ago.
- Discrepancies may arise from sediment mixing, analytical uncertainties, or alternative explanations for the 60Fe signal.
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