1896 Henri Becquerel – Discovery of Radiation

From chance observation to scientific breakthrough, Becquerel’s discovery revealed photography’s power to capture the invisible.

Henri Becquerel’s discovery of natural radioactivity through a photographic plate marks a milestone in the intersecting histories of photography and science. Until then, photography was seen primarily as a tool for recording the visible world. Becquerel’s experiment—placing uranium salts on a light-shielded photographic plate—revealed that the medium could also register forces beyond human sight.

The ghostly blackening of the plate unveiled a new, unseen energy: radioactivity. This discovery challenged prevailing ideas of photographic sensitivity, proving that silver halide emulsions could respond not only to light but also to penetrating, ionising radiation.

Becquerel’s breakthrough expanded the role of photography into a vital instrument of scientific exploration. It paved the way for new imaging methods across the electromagnetic spectrum, from X-rays to infrared photography, and catalysed innovations in radiation detection. The legacy of this plate extends into physics, medicine, and technology, where photography continues to transform invisible phenomena into visible evidence.

Credit: Henri Becquerel, Public domain, via Muséum national d’Histoire naturelle, Paris / Wikimedia Commons
Author: Henri Becquerel (1852–1908)
Title: Photographic plate showing the effects of uranium salts
Date: 1896
Archive: Muséum national d’Histoire naturelle, Paris
Source: Wikimedia Commons
Original file: 492 × 397 pixels, file size: 28 KB, MIME type: image/jpeg
Available information: This photographic plate was created by Henri Becquerel in February 1896 at the Muséum national d’Histoire naturelle, Paris, where he held the Chair of Applied Physics. It records the spontaneous emission of radiation from uranium salts, producing an image without exposure to light. Preserved within the museum’s collections, the plate is considered the first photographic evidence of natural radioactivity and marks a turning point in both physics and the history of photography.

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Exploring the Influence of Discovery and Proof in Physics across Zero Baseline

Photography has long served as both a revealer of the unknown and a confirmer of scientific predictions. From the unexpected discovery of radiation and X-rays to the visual proof of electromagnetic waves, subatomic particles, and astrophysical phenomena, images have extended scientific vision beyond human senses. Advances in detection methods, exposure control, and imaging media have made it possible to record events once hidden, turning abstract equations into visible traces and serendipitous discoveries into new fields of physics. In doing so, photography has both revealed new phenomena and reinforced theoretical models, enabling further optical investigation alongside simulation and data modelling—together expanding our ability to explore and understand the natural world.

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