About us

According to its regulations, the practice group of the Rudolf Wolf Society, headed by Patrick Enderli from Thun, aims to promote and maintain the sun observation activities of its members.

The practice group is committed to preserving and passing on the traditional Zurich observation method and to the long-term documentation of solar activity using modern instruments.

Some of the members of the practice group after the common visual sun observation and shop talk in the garden of the observatory Zimmerwald. The joint observation and the regular in situ comparison with the results of the standard observer are indispensable elements in the long lasting quality assurance of the joint visual observation program, which exists since 1986, to continue Wolf's series of sunspot relative numbers.

The working areas of the practice group include short and medium-term observation and measurement campaigns, which serve the study of individual activity phenomena of the sun or the testing of new instruments and additional equipment as well as the learning of new documentation and evaluation techniques. For this purpose the members of the practice group can use the instruments of the Uecht solar tower in Niedermuhlern near Bern.

On request, the members of the practice group are also available to an interested audience for demonstrations and lectures.


On the sun tower Uecht in Niedermuhlern, the members of the practice group have powerful telescopes at their disposal for carrying out photographic observation campaigns in white light, in Ca II K as well as in H-alpha. The control of the instruments and cameras as well as the image processing on the computer is done either from the two nearby observation rooms, which offer enough space for up to three observation teams of 2-3 persons each, or by remote control via internet.