The Great Telescope
In the early 1840’s, the Third Earl of Rosse designed and built the largest telescope in the world - The Great Telescope (also known as The Leviathan of Parsonstown). With this telescope, he discovered the spiral nature of galaxies, and from 1845-1914 this remained the largest telescope in the world! During this time, anyone wishing to witness this phenomenon had to travel to Birr. People came in their hundreds from across Europe and beyond, either to observe the stars with Lord Rosse or simply to marvel at this incredible feat of engineering in the heart of Ireland.
Standing at an impressive 72 feet long with a mirror measuring 6 feet in diameter, the telescope was not just a scientific instrument, but a symbol of human curiosity and innovation, built using cutting-edge engineering techniques of its time.
Today, The Great Telescope sits in the heart of the Demesne and a visit to our Historic Science Centre demonstrates how the extraordinary telescope was built in the castle workshops by Lord Rosse and the people of Birr.
Astronomy remains an active pursuit at Birr Castle Demesne, with research continuing through I-LOFAR, a state-of-the-art radio telescope project located within the Demesne. Supported by a €1.4 million grant from Science Foundation Ireland to Trinity College Dublin, this facility connects Ireland to the international LOFAR network, enabling advanced radio astronomy research. The project is aptly situated within Birr Castle Demesne, following in the footsteps of the historic Leviathan telescope.
For more information on the I-LOFAR project please visit www.lofar.ie (a project run by Trinity College Dublin).
World Heritage Aspirations
Ireland has three historic observatories that possess a remarkable astronomical heritage, one that stretches all the way back to the Georgian era. These are the observatories of Birr, Armagh and Dunsink. All three remain active today, places where frontline science continues to be carried out while also serving as centres for communicating science to the public and explaining it to students. Their heritage is entwined with the telescopes they possess, pioneering instruments of their time that are still found largely in situ today, in how these telescopes were used, and in the science that was carried out there. The heritage is so strong and so worthy of greater protection that these three Irish observatories have come together to seek UNESCO world heritage listing.
World Heritage is a designation provided by UNESCO – the United Nations Educational, Scientific and Cultural Organisation – for places that have outstanding universal value to humanity and are worthy of protection so that they can be appreciated and enjoyed by future generations.
