Detection of Mercury in the 411-year-old Beard Hairs of the Astronomer Tycho Brahe by Elemental Analysis in Electron Microscopy

Abstract

Hairs more than 400 years old of the famous astronomer Tycho Brahe were studied by electron microscopy to evaluate the hypothesis that Johannes Kepler murdered his teacher Brahe by mercury intoxication. The beard hairs showed a well-preserved ultrastructure with typical hair scales and melanosomes. The authors detected an accumulation of electron-dense granules of about 10 nm inside the outer hair scales, but not in the hair shaft and roots. At the places of these heavy-metal-containing granules they detected mercury besides other elements by energy dispersive X-ray analysis (EDX, Oxford, UK) in a field cathode scanning electron microscope (SEM, Gemini, Zeiss). The mercury-containing granules were found over the whole length of hairs, but only in the outer hair scales. Nevertheless, surface coatings of hairs were free of mercury. This distribution of mercury does not support the murder hypothesis, but could be related to precipitation of mercury dust from the air during long-term alchemistic activities.

KEYWORDS::

• Beard hairs
• electron microscopy
• elemental analysis
• forensic medicine
• mercury intoxication

ACKNOWLEDGMENTS

We thank E. K. Jessberger (Institute of Planetology, University of Münster, Germany) and R. Wegener (Department of Forensic Medicine, University of Rostock) for providing the beard hairs of Tycho Brahe. Furthermore, we are thankful to V. Weirich and J. Nowotnik from the Department of Forensic Medicine, University of Rostock, Germany, who investigated the DNA of the hairs and performed some molecular genetic studies, not presented in detail in this paper. We also thank Ute Schulz and Gerhard Fulda of the Electron Microscopic Centre, University of Rostock, for technical assistance.

Declaration of interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.