Originally, the permanent exhibition of the collection of the Astronomical-Physical Cabinet was housed in the Orangerie. Due to a necessary basic renovation of the building, the museum area is currently closed, and the exhibition can be seen in small special presentations at the Hessian State Museum.

The yellow shining facade of the Orangerie Palace in the Karlsaue with the two corner pavilions is visible from afar. The Orangerie was built in the early 18th century by Landgrave Carl. Numerous orange and laurel trees overwintered in the central building. The two corner pavilions – kitchen pavilion and marble bath – as well as the central Apollo Hall were used by Landgrave Carl and his wife as a summer residence and for festivities. In the 1760s, his grandson Landgrave Friedrich observed the course of the moon and the planets with telescopes on the roofs of the Orangerie. Today you can discover Hesse's largest planetarium here.