Dunsink Observatory is one of the longest-established observatories in the world and holds the distinctive title of the oldest scientific institution in Ireland. Built on the south slope of a low hill, the observatory was established in 1785 in Dunsink near Dublin. Today, Dunsink Observatory is of interest to astronomy buffs as well as visitors from around the world. The building is located 5 miles / 8 kilometres northwest of Dublin City centre, just off exit 5 of the M50 motorway.
While admission is normally only admitted by via prior arrangement, the observatory holds public open nights each first and third Wednesday night of winter months (October-March). Admission on these open nights is FREE but visitors must pre-register for tickets via the official website. If weather permits, visitors can observe the celestial bodies through a three different telescopes. The largest telescope, known as the 12-inch Grubb, is a refracting telescope built by Thomas Grubb of Dublin with an achromatic lens donated by Sir James South. The observatory also offers audio-visual presentations and lectures on astronomical topics, including a 3-D movie of a trip through space followed by a question and answer session designed to answer astronomy-related queries. The clocks that once set the time standard for Ireland until the first World War are still on display in the observatory.
Dunsink Observatory originally belonged to Trinity College and was purchased by the state in 1947 when the School of Cosmic Physics was being established as part of the Dublin Institute for Advanced Studies. The most famous director of the observatory was the eminent 19th century mathematician William Rowan Hamilton, who was known for his Hamiltonian formulation of dynamics and for the discovery of quaternion mathematics.
Dunskink Observatory. Image by nectarous[