Zimmerwald Observatory

Zimmerwald Observatory, also called the Swiss Optical Ground Station, is operated by the Astronomical Institute of the University of Bern. Its work combines satellite laser ranging with optical observations. The ZIMLAT telescope contributes ranging measurements to the International Laser Ranging Service and the International Terrestrial Reference Frame. ILRS identifies the station as ZIML, number 7810. The position shown is the published laser-station reference position at Zimmerwald. Sources: [ILRS station profile](https://ilrs.gsfc.nasa.gov/network/stations/active/ZIML_station_info.html); [ILRS operational station inventory](https://ilrs.gsfc.nasa.gov/network/stations/active/index.html); [institutional site information](https://www.aiub.unibe.ch/research/zimmerwald_observatory/index_eng.html). Sources checked 17 October 2026.