Reaching for the Dark Skies in Vienna

At the heart of IAU is the desire to maintain dark, starry night skies, not only for the livelihood of its members but to preserve humanity’s cultural heritage. In line with this goal, the presence of the IAU GA in Vienna has been leveraged to created a number of events for attendees and the general public. These events are the products of Commission C.B7 on site protection, working with its IAU partners, Commission C1 on education and the Office of Astronomy Outreach (OAO).

Milky way over light pollution in Pic du midi, France / Haute Pyrénées. (Luc Oerrot)

Education was the focus during the week before the GA. Three workshops were hosted at Kuffner Observatory and the University of Vienna by Global Hands-on Universe (GHOU), Galileo Teacher Training Programme (GTTP) and Commission C1. Each workshop discussed light pollution and utilised the Quality Lighting Teaching Kit.

During the first week of IAU GA, participants and the public were able to experience the “E-Light Pollution Exhibit” at the Natural History Museum in Vienna, which featured 100 photos illustrating light polluted and starry night skies. The exhibition was followed by a public talk on the importance of fighting light pollution. The new film “Saving the Dark” was also screened for museum event attendees.

On Friday, 24 August at 09:00 AM, the Commission C.B7 will be holding a joint technical session with the CIE (the international illumination society that sets technical standards and measurements for outdoor lighting). It will be held at the Kuffner Observatory in Vienna and will include presentations from IAU on dark sky criteria, measurements, modelling and the impact of LEDs.  The CIE will present information on outdoor lighting applications and measurement of obtrusive lighting. The discussion will highlight needed measurements, development of standards, and preparation for a technical workshop to be sponsored by the UN Commission on the Peaceful Uses of Outer Space. The day will conclude with a Commission business meeting.

On Sunday, 26 August, again at Kuffner, there will be a rich programme of presentations on individual site protection efforts, the Radio Frequency Interference threat, and international approaches to education and outreach to protect dark skies in the context of sustainability. The keynote speaker will be Fabio Falchi of Italian Light Pollution Science and Technology Institute (ISTIL) who leads the world atlas of artificial sky brightness. Distinguished experts in the field will be talking both Friday and Sunday with the focus on Sunday being site protection and education.

A very special trip is planned for Thursday, 30 August to a dark and starry night sky location, only 35 km from Vienna called the Großmugl Starlight Oasis. The round trip transportation will cost around 24€ and dinner will be less than 20€. Interested participants are requested to meet at the IAU GA registration area at the Austria Center Vienna (ACV) before 06:30 PM to leave at 06:30 PM. The tour will be lead by the director of Kuffner Observatory, Dr Günther Wuchterl. Participants are required to register for the tour by emailing to

Acknowledgement: Thank you to Richard Green, president of Commission C.B7 for contributing to this article.

CONSTANCE WALKER is a scientist at the National Optical Astronomy Observatory in Tucson, Arizona, USA, president-elect of the IAU commission C.B7 on site protection (e.g. dark and quiet skies) and co-chair of the IAU100 Dark Skies for All Project.