Sir, - The Irish Times (May 21st) contains a very interesting article about the replacement mirror for the Birr telescope. The restoration of the telescope, given its contribution to our scientific heritage, is to be applauded.
Unfortunately the restored Birr telescope, with its 1.8 metre mirrors, will not be the second largest instrument in Europe as stated in the article. Far from it. For example, in Southern Spain, the Max Planck Society operates both 3.5 metre and 2.5 metre telescopes along with a suite of smaller instruments. There are numerous bigger telescopes in the Canaries including the William Herschel (4.2m), the Isaac Newton (2.5m), the Nordic Optical telescope (2.2m), the Galileo telescope, and so on. In Germany, near Jena, there is a 2 metre telescope and in the Crimea, a 2.6m telescope. There are others, these are just the ones that come to mind.
regarding whether the Birr telescope will be in demand by scientists, one has to remember that it is being restored as a historical instrument and was never intended for modern astronomical research. Observing conditions in Ireland, even on nights when the sky looks clear, are very poor. Modern telescopes are sited on remote mountain tops, such as those of the Canary Islands, free from light pollution and with low levels of air turbulence. Irish astronomers are fortunate in having access to such facilities at which they carry out their observations before returning home to analyse their days. - Yours, etc, Prof Tom Ray, Astrophysics Sections, Dublin Institute for Advanced Studies,
Dublin 2.