Marcel and I decided to do a brief trip this past December to the midlands of Ireland.
Since joining NOVAC a few years ago, we have seen how members share about their astronomy influenced trips and so I googled telescopes of Ireland, and the Great Telescope at Birr Castle came up frequently. We added it to our itinerary
and packed our NOVAC hats.
On the gates of Castle Birr in Latin it said “For God and Country to the Stars.” The Great Telescope at Birr Castle has its place in history. As the brochure describes it was “built by the 3rd Earl of Rosse in 1845, this telescope was the biggest in the world for over 70 years. Using this telescope the Earl discovered the Whirlpool Nebulae, which was the very first hint at the existence of other galaxies.”
Once you buy your tickets you are given a map and off you go – we also signed in as members of NOVAC in the guest book. You are put first on a winding tree-lined path and first you see a magnificent castle. The time of year we were there (December) it was not open. We were not, though, there to see the castle with it’s moat (which was used in the creation of the telescopes aperture) and soon we turned a corner and there was the great telescope in the middle of a very large field.
Leviathan of Parsonstown; The Great TelescopeIt’s really large! It was a reflecting telescope and built onsite in Castle workshops and named Leviathan of Parsonstown. The large aperture was 72 inches, five inches thick and weighed three tons. Today one of the mirrors is at the science center in London, but the rest is pretty much right there – we walked around the entire structure and you can get close. The walls are 15m high (appx 49 feet) and 21m long (appx 69 feet). The telescope tube is 17m (appx 55 feet).
How did it get aligned?The platform was movable so the observer could move along with the object of study. The design, though, restricted azimuthal movement. Pulley’s, cables and cranes and multiple helpers assisted as the earth rotated. High winds made this precarious, but no serious accidents occurred. On the property there are meridian rocks and ancient trees that were used for such alignments and can still be seen today.
What did Earl’s work achieve?The Earl often did astro sketching while using a red lantern so as not to disturb his night vision. He is known to have discovered the arms of the Whirlpool Nebulae – M51 and he allowed scientists from around the world to do similar studies, in particular expanding Messier’s work. The great telescope led us to understand that Nebulae were other galaxies and not part of our own. There is so much more in this area of how it is used- suggest you read up on this before you go.
The grounds & the Irish Low Frequency Array — I-LOFAR
The grounds are full of astronomical information and inspiration. In addition to markers representing the solar system, they have grown lime trees in the form of the whirlpool spiral (M51). There is a moon gate installed to mark the millennium. There are also extensive gardens and information not related to astronomy I won’t share here, but a lot to be seen in addition to astronomy.
On the grounds through a beautiful path and over a babbling brook and swans on a lake nearby is the Irish Low Frequency Array – I-LOFAR. This radio telescope was built in 2017, is “part of an international network of radio telescopes….it is studying the sun, stars, planets and galaxies.” You can’t get particularly close, but it is fun to see. Nearby they are building what were said to be eco-friendly cabins for future visitors and science projects. Perhaps a future NOVAC study trip….
When we first came the shopkeeper encouraged us to go towards a room to see the museum. We said we would consider it after looking at the great telescope. Honestly, I thought this was just a one room museum for kids. On the way out, he encouraged us again… ok
We were there for a long time… This is a proper astronomers museum from a time past gone. It was probably ten rooms all through an old building (stables?). It is probably the least underappreciated part of the property and one of the most interesting. If you are into the building of telescopes, and other related engineering ‘gadgets’ this is a must visit place for you to see and take the proper time. The artifacts from building the leviathan are all there, all the studies including a tool the Earls son used to determine the temperature of the moon. There is a letter from Neil Armstrong after a visit himself. Honestly, the turn of the 20th century (albeit dusty) museum would have been worth just visiting itself. A real passage through space and time.
Hope you have enjoyed a taste of this hidden gem. Happy to answer any questions. We will go back for sure and hope you are inspired as well.