The architecture of the expansion for the European Southern Observatory (ESO) main administration respects the green belt south of the research campus and the extroverted character of the existing building. Analogous to the formal architectural vocabulary of the existing building, the new structure, with its offices, seminar spaces, lecture hall and conference room, was designed based on segments of circles and free of structural columns and seemingly hovers above the landscape.
Adjacent to the new building is the circular shaped, two storey technical building with its assembly hall.