Timothy J. Jorgensen is associate professor of Radiation Medicine, and Director of the Health Physics and Radiation Protection Graduate Program, at Georgetown University in Washington DC. His scientific expertise is in radiation biology, cancer epidemiology, and public health. He is board certified in public health by the National Board of Public Health Examiners (NBPHE). He serves on the National Council on Radiation Protection (NCRP), he chairs the Georgetown University Radiation Safety Committee. His research interests include the genetic determinants of cellular radiation resistance, and the genes that modify the risk of cancer. He is the author of the award-winning book "Strange Glow: The Story of Radiation" (Princeton University Press; 2016) -- a book that explores the risks and benefits of radiation use in daily life; and also "Spark: The Life of Electricity and the Electricity of Life" (Princeton University Press, 2021) -- a book that looks at the role of electricity in the body.