Kirlian photography is a process developed in the early 1940s by Seymon and Valentina Kirlian to record the phenomenon of corona discharges from living matter.^[1] A corona discharge is an electrical discharge created by the ionisation of the gas surrounding a high-voltage conductor.^[2]

The process entails placing a sheet of photographic film on top of a metal plate. The object to be photographed is then placed directly onto the film, and a high-voltage current is momentarily applied to the object, thus creating a corona discharge resulting from the ionisation of the surrounding air, which is captured on the film.^[1]

The Kirlians came to believe that their images were evidence of a life force or energy field that reflected the physical and emotional states of their subjects, and could be used to diagnose illnesses. In 1961 they published their first article on the subject, in the Russian Journal of Scientific and Applied Photography.^[3] This led in turn to a large number of pseudoscientific claims about “auras” and “biofields”, none of which have been supported by scientific evidence.^[4][5] The most likely cause of the variations observed in the images of the same individual over time is simply changes in skin conductivity owing to temperature, humidity, and other environmental factors.^[1]