The World’s oldest working Planetarium

Planetarium Eise Eisinga, Franeker, 1774. Photo: Wikipedia.

Else Eisinga was born in a small Frisian village in 1744. He worked from early age on the the wool combing business of his father and he became himself a true master of this craft, and even won an international prize in 1820. That is not why he is still well known however.

His self-study in astronomy and mathematics enabled him to write books (into the Dutch language, he was not educated in Latin) on these subjects at the age of fifteen and eighteen.

His ´Theory of the Basic Principles of Astronomy or Science of the Course of the Stars´, his ´Gnomics or Sundials, all Constructed by Compasses and Ruler for the Northen Lattitude of Dronrijp´ (his Frisian village of birth, ed.) and his book in which he calculated the eclipses of the sun and the moon were just the beginning of an astonishing scientific career, in his spare free time and in his own house in Franeker.

Eisenga built a model of the solar system into his living room in 1774. He managed to create a accurate depiction of the system by reducing the scale by a factor of one trillion. One millimetre on the ceiling represented one million kilometres.

All the planets, stars, sun, earth and moon in his Planetarium move exactly as they do in reality, and they have been doing so ever since, day in, day out, year in, year out and extremely accurate. The system was and is driven by a mechanism of wooden hoops and disks with more than 6 000 nails serving as gear teeth.

His son and later his granddaughter and other descendants took over the management when he died in 1828, a celebrity and highly decorated scientist, who kept working as wool comber however.

The Municipality of Franeker took over the building in 1859, but members of the family continued the management until 1922, when the municipality of Franeker appointed the custodians. Although the model dates from 1774, the Planetarium is still topical and rightly praised for its ingenuity.

(Source: A. Warmenhoven, Royal Eise Eisinga Planetarium, Franeker).