The Royal Eise Eisinga Planetarium is an 18th-century orrery in Franeker. It is currently a museum and open to the public. The orrery has been on the top 100 Dutch heritage sites list since 1990 and nominated as a UNESCO World Heritage Site candidate based on its long history as a working planetarium open to the public and its continued efforts to preserve its heritage.
The orrery was built from 1774 to 1781 by Eise Eisinga. An orrery is a planetarium, a working model of the solar system. The 'face' of the model looks down from the ceiling of what used to be his living room, with most of the mechanical works in the space above the ceiling. It is driven by a pendulum clock, which has 9 weights or ponds. The planets move around the model in real time, automatically. The planetarium includes a display for the current time and date. The plank that has the year numbers written on it has to be replaced every 22 years.
The Eise Eisinga Planetarium is the oldest still working planetarium in the world. To create the gears for the model, 10,000 handmade nails were used. In addition to the basic orrery, there are displays of the phase of the moon and other astronomical phenomena. The orrery was constructed to a scale of 1:1,000,000,000,000 (1 millimetre: 1 million kilometres).
References:Rosenborg Palace was built in the period 1606-34 as Christian IV’s summerhouse just outside the ramparts of Copenhagen. Christian IV was very fond of the palace and often stayed at the castle when he resided in Copenhagen, and it was here that he died in 1648. After his death, the palace passed to his son King Frederik III, who together with his queen, Sophie Amalie, carried out several types of modernisation.
The last king who used the place as a residence was Frederik IV, and around 1720, Rosenborg was abandoned in favor of Frederiksborg Palace.Through the 1700s, considerable art treasures were collected at Rosenborg Castle, among other things items from the estates of deceased royalty and from Christiansborg after the fire there in 1794.
Soon the idea of a museum arose, and that was realised in 1833, which is The Royal Danish Collection’s official year of establishment.