1932 Carl D. Anderson – Cloud Chamber First Positron

Carl Anderson’s photo of a positron transformed photography, proving scientific theories and expanding perception.

Carl Anderson's photograph of the positron marked a turning point in the history of photography, catapulting it as a critical scientific tool. This image was the first to use photography to confirm the existence of subatomic particles, thereby becoming a proof of theoretical physics predictions. Anderson's technique, employing a cloud chamber to visualize the trajectories of charged particles like positrons, rendered the invisible visible.

These particle paths, captured with high-precision cameras, revealed tiny droplets tracing the positron’s journey through vapor. The photograph not only served as direct visual evidence of antimatter but also challenged our understanding of reality and visibility. Its implications were profound, influencing both the technological trajectory of photographic and scientific equipment and merging the realms of art and science. By extending the boundaries of what photography could capture, Anderson’s work enriched human perception and knowledge, paving the way for new scientific discoveries and artistic explorations.

Credit: Carl D. Anderson (1905–1991), Public domain, via Wikimedia Commons
Author: Anderson, C. D. (1932)
Title: The first cloud chamber photograph of a positron's path
Date: 2 August 1932
Archive: American Physical Society
Source: Wikimedia Commons
Original file: 2,408 x 2,374 pixels, file size: 2.92 MB, MIME type: image/png
Available information: Anderson, Carl D. (1933). “The Positive Electron”. Physical Review 43 (6): 491–494. DOI:10.1103/PhysRev.43.491.