|Ger de Bruyn, Michiel Brentjens and George Heald
| Following a LOFAR Magnetism Key Science Project meeting at the Dublin Institute of Advanced Studies (DIAS) in Dublin, Ireland, in late October 2010, we were invited by Peter Gallagher and Anna Scaife to visit Birr Castle, located in the middle of Ireland. They wanted our opinion on the suitability of a potential site for an Irish LOFAR station. A LOFAR site requires a flat terrain of about 100-200m, with unobstructed view down to elevations of about 20 degrees. A suitable terrain, the Wetherlock field in the beautiful Birr Castle Demesne, has been offered by the current Lord Rosse.
The photograph shows the happy Dutch delegation in front of the famous telescope located there. The bottom-left inset shows the telescope with the beautiful autumn colours of the Birr Castle Demesne. When the telescope was completed, in the middle of the 19th century, it was by far the largest optical telescope (72 inches!) in the world. The telescope was conceived and built by the 3d Earl of Rosse (inset, top right) in the 1840ies. It appears that his motives for constructing a big telescope were very similar to those of the LOFAR community!
The Birr Castle site appears very well suited for low frequency astronomy and has the lowest RFI of any LOFAR site in Europe. Birr Castle is located 1000 km West of Exloo, the Netherlands, where the core of LOFAR is located. I-LOFAR will, in combination with the other European LOFAR stations, provide subarcsecond resolution at frequencies down to 30 MHz ! The white paper for an Irish LOFAR station, prepared by a consortium of institutes in Ireland, can be downloaded from their website (www.lofar.ie).