Equatorial refractor telescope

The telescope is the primary tool used by astronomers: it can be used not only for observation but also for various types of astronomical measurements.This model is based on the same optical principles as those used by Galileo when he built his telescopes three centuries earlier. The objective lens is about 20 cm in diameter. Its use of a motorized system makes it possible to automatically follow the apparent motion of celestial objects. Purchased by the Osservatorio Astronomico di Brera from the Milanese company Salmoiraghi, one of the leading manufacturers of scientific instrumentation, it was soon joined by even more powerful tools.