Experimental evidence that potassium is a substantial radioactive heat source in planetary cores

@article{Murthy2003ExperimentalET,
  title={Experimental evidence that potassium is a substantial radioactive heat source in planetary cores},
  author={V. Rama Murthy and Wim van Westrenen and Yingwei Fei},
  journal={Nature},
  year={2003},
  volume={423},
  pages={163-165}
}
The hypothesis that 40K may be a significant radioactive heat source in the Earth's core was proposed on theoretical grounds over three decades ago, but experiments have provided only ambiguous and contradictory evidence for the solubility of potassium in iron-rich alloys. The existence of such radioactive heat in the core would have important implications for our understanding of the thermal evolution of the Earth and global processes such as the generation of the geomagnetic field, the core… 

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