At a Glance
- Event: History of Science Symposium & City Walk
- Date: Saturday, February 21, 2026 (Symposium) & Sunday, February 22, 2026 (Tour)
- Topic: Discovery and Application of UV Radiation
- Award: „Radiation of the Year 2026“
- Organizer: Jenaer Zentrum für Romantikforschung, Deutsches Optisches Museum, Romantikerhaus Jena et al.
Jena, 16.02.2026 – Jena is considered a City of Light worldwide, but many are unaware that a significant part of the light spectrum known today was discovered right here. This week, a historical milestone in physics takes center stage: the discovery of ultraviolet radiation by Johann Wilhelm Ritter over two centuries ago.
An Experiment Makes History
It was February 22, 1801, when the experimental physicist Johann Wilhelm Ritter (1776–1810) made scientific history in Jena. Ritter, who was close to the Romantic movement and in active exchange with the intellectual giants of his time, conducted a decisive experiment. He split sunlight using a prism and investigated the effect of different color ranges on silver chloride.
The result was astonishing: silver chloride, which is known to turn black when exposed to light, reacted most strongly in a range that was not visible to the human eye at all – beyond the violet end of the spectrum. Ritter correctly concluded that there must be invisible radiation there. What began as a scientific curiosity is now indispensable in our daily lives and technology.
From the Laboratory to High Technology
The significance of Ritter’s discovery extends to the present day and significantly shapes Jena as a technology hub. Without the knowledge of ultraviolet light, numerous modern applications would be unthinkable. Two further milestones closely linked to the Saalestadt are particularly noteworthy:
- UV Microscopy: As early as 1904, the foundation for microscopy with ultraviolet light was laid in Jena, enabling a significantly higher resolution than conventional light microscopy.
- EUV Lithography: A current example of the relevance of this radiation is extreme ultraviolet lithography. It is the key technology for manufacturing state-of-the-art microchips and processors, where Jena’s optical expertise plays a leading global role.
Symposium and City Walk on the Weekend
To honor this groundbreaking achievement, UV radiation was named “Radiation of the Year 2026” as part of an upcoming conference. The Jenaer Zentrum für Romantikforschung, together with renowned partners such as the Deutsches Optisches Museum and the Fachverband für Strahlenschutz, is organizing a special program.
On Saturday, February 21, 2026, a history of science symposium will take place. It will not only highlight the historical context but also address current knowledge about the benefits and dangers of UV radiation. Interested citizens also have the opportunity on Sunday, February 22, 2026 – exactly on the anniversary of the discovery – to participate in a cultural and technological history city walk.
These events offer a rare opportunity to experience the connection between historical Romanticism in Jena and modern high technology firsthand.
Sources:
Original
Transparency Note: This article was created automatically, editorially reviewed, and expanded with AI support.