The starting point for the considerations presented in the article are Monika Niwelińska’s radiographs from the “Trinity Site” series. The artist left photographic plates in the area where a ground-based test of atomic weapons was carried out in 1945. The irradiated earth affects the photosensitive material, changing its color and texture. In this way, the materiality of the soil and the radioactive activity induced by human experiments literally leave their mark on the artistic work. The artist’s works allow for a new interpretation of the groundbreaking text by Rosalind E. Krauss Notes on the Index, which changed thinking about the artistic representation of twentieth-century art. Read in the context of contemporary theories of materiality (including Karen Barad), it indicates the connections between image, trace and energy.