Sun & Moon Colloquium
Three online sessions in English to explore East and West in us
May 7, 2026, 13:30 - 15:00 CEST Recording Session I
May 21, 2026, 13:30 - 15:00 CEST
June 4, 2026, 13:30 -15:00 CEST
(19:30 - 21:00 in Taiwan, 20:30 - 22:00 in Japan)
Access Online-Meeting:
- https://goetheanum-ch.zoom.us/j/88932261500?pwd=4gpMWXQQ7wgNrqfYdbr3EGBVjjkiuV.1
- Meeting-ID: 889 3226 1500
- Access code: 021752
Each online session starts with an introduction to the topic, continues with a short dialogue between Shy Tyng Kai, Kai Iruma and Oliver Conradt and opens up in the last part to a discussion with all participants.
We sincerely hope that, through this sharing and mutual search for something, that unites us in East and West, we could together find new perspectives for the world situation today.
Rudolf Steiner’s Aphorisms in English:
- https://rsarchive.org/Articles/GA036/English/Singles/WEAphr_index.html
- The German original can be found in GA 83, 3rd edition 1981, Rudolf Steiner Verlag, pp. 361-372.
Kai Iruma, Corepresentative for the Rudolf Steiner Society in Japan
Shy Tyng Kai, Member of the Preparation Group for the Anthroposophical Society in Taiwan
Oliver Conradt, Leader of the Mathematical-Astronomical Section at the Goetheanum
Ueli Hurter & Stefan Hasler, Members of the Executive Council
Dark Sky Week 2026
Contributions of the Mathematical-Astronomical Section
International Dark Sky Week (April 13-20, 2026) is a global celebration of the night. From the darkness that supports a restful night’s sleep to the wonder we experience beneath starry skies, the night plays a vital role in our wellness, the well-being of wildlife, scientific discovery, cultural heritage, and more. Yet with the rapid rise of light pollution, we risk losing the natural night we depend on. The time to act is now!
All three talks prepared by the Mathematical and Astronomical Section for Dark Sky Week, in collaboration with the speakers, can be purchased together as a video package. Oliver Conradt's introduction is freely available to everyone.
Astronomie & Geisteswissenschaft
Das nächste Kolloquium der Reihe Astronomie & Geisteswissenschaft findet vom 21. bis 23. November 2025 am Goetheanum in Dornach statt. Weitere Informationen
Math in Movement. How Projective Geometry and Eurythmy Embody the Invisible
Goetheanum in Dornach (Switzerland); June 26-28, 2026.
Workshop with Russell Arnold & Jane Ranck.
Russell Arnold, PhD. Is a Co-Worker in the Section for Math and Astronomy at the Goetheanum. His research in projective geometry spans from applications in the realm of etheric-formative forces to a revival of metamorphic geometry in the mainstream of mathematics.
Jan Ranck is active internationally as a performer, teacher and trainer of eurythmy and eurythmy therapy. She is the founding director of the Jerusalem Academy of Eurythmy and the Jerusalem Eurythmy Ensemble.
The conference language is English only.
The detailed program can be found HERE. Please register by 19 June 2026 via https://goetheanum.ch/en/events/masd26.
Paper on Bud Research
In the framework of the research project Rhythmical Change of Shape in Mistletoe Berries According to Moon and Zodiac Constellations by Renatus Derbidge at the Natural Science Section of the Goetheanum a first paper was published in the open access journal PLOS ONE. It presents methods and software to capture and measure the shape changes of mistletoe berries and leaf buds over time. The paper describes the software used to automatize a number of tasks including contour recognition, optimization of fitting the contour via hill-climbing, derivation of the path curves, computation of Lambda and blinding the pictures for the operator. The validity of the program is demonstrated by results from three independent measurements showing circadian rhythm in mistletoe berries. The program is available as open source and will be applied in a project to analyze the chronobiology of shape in mistletoe berries and the buds of their host trees.
Coauthors of the paper are Linus Feiten (Faculty of Engineering, Chair of Computer Architecture, University of Freiburg, Freiburg, Germany), Oliver Conradt (Section for Mathematics and Astronomy, Goetheanum, Dornach, Switzerland), Peter Heusser (Centre for Integrative Medicine, University of Witten/Herdecke, Witten, Germany) und Stephan Baumgartner (Hiscia Institute, Society for Cancer Research, Arlesheim, Switzerland).