The history of the Institute for Astronomy can be traced back to June 13, 1855, when the Swiss Federal Government nominated Rudolf Wolf as Professor of Astronomy at the newly founded Polytechnicum, which was later renamed as ETH (Eidgenössische Technische Hochschule). On October 17 of the same year Wolf was also nominated as the Librarian (director) of the new ETH library, which had the additional benefit that the ETH now owns an outstanding historical astronomical library which includes original works by Copernicus, Kepler and Galileo Galilei.
Today Rudolf Wolf’s name is still associated with the Wolf sunspot number. His long-term observations and historic research were pivotal in establishing the cyclic behaviour of sunspots. Between 1862 to 1864, the “Eidgenössische Sternwarte” (federal observatory) was built according to the plans of Gottfried Semper, the famous architect. This building still stands near to the University Hospital, but is no longer occupied by the Institute.
All of Wolf’s immediate successors – Alfred Wolfer (1894-1926), William Otto Brunner (1926-1945), and Max Waldmeier (1945-1979) - chose the sun as their field of research, and sunspots continued to be observed and registered. In 1980 Jan Stenflo succeeded Max Waldmeier as Professor of Astronomy, this work was terminated and a new Institute for Astronomy was founded in the place of the “Eidgenössische Sternwarte”. Although Stenflo’s main interest remained the sun and its magnetic fields, new subjects, such as stellar astrophysics and the interstellar medium, were introduced into the Institute’s activity.
The Institute of Astronomy also became a member of the ETH Department of Physics. Already in the early 1990's, the Department of Physics was keen to expand the range of astrophysical research into new directions, especially in view of Switzerland’s strong engagement in both ESA and ESO. The first step in this direction came about in 2002, with the appointment of two new Chairs, Simon Lilly (Observational Cosmology) and Marcella Carollo (Extragalactic Astrophysics).
Following the retirement of Jan Stenflo in 2007, it became possible, with continued support from the Department of Physics, to appoint two further Chairs. Michael Meyer (Star and Planet Formation) joined the faculty in 2009, cementing the blossoming PLANET-Z initiative of the Institute, and Alexandre Refregier (Fundamental Cosmology) was elected in 2011.
As a result of this growth, the Institute for Astronomy now stands with the four elected Chairs, SNF Professor Justin Read, and a scientific staff that will, with the establishment of Refregier's Chair, consist of more than 20 PhD-level researchers, about 35 PhD students, and six technical and administrative staff.