Aside from a plaque that reads “Planetarium,” you would hardly be able to tell that inside this seemingly cozy Dutch house lives the oldest accurate moving model of our solar system. What’s even harder to believe is that the model, known as an “orrery” and built in 1781, is still functioning to this day!

Eise Eisinga, a wool comber and amateur astronomer living in Franeker, Netherlands, decided to build the model in 1774 after an alignment of the planets earlier that year induced mass panic among the Dutch. People were terrified that a planetary collision was imminent. Eisinga hoped his model would help prove that nothing of the sort was going to happen.

The model was built from oak wood, nine weights, a pendulum clock, and over 10,000 hand-forged nails. Each planet continues to orbit the sun at an appropriate speed (i.e., earth, once a year; Saturn, every 29 years). The museum is also home to a variety of old astronomical instruments, as well as modern-day stargazing equipment.