A little ramble through 19th century astronomy - Observations by Lord Rosse

 

Academy Newspaper Saturday 6^th March 1880 

 

Observations of Nebulae and Clusters of Stars made with the Six-foot and Three-foot Reflectors at Birr Castle from the Year 1848 to about the Year 1878. By the Earl of Rosse.

Parts I. and II. in vol. ii. of the Scientific Transactions of the Royal Dublin Society, Lord Rosse has published the observations of nebulae procured by means of the great telescopes of his observatory in the course of thirty years.

 The late Earl, the constructor of these great instruments, had brought out several papers on a selection of the nebulae and clusters observed, the last one having appeared in the Philosophical Transactions of the Royal Society for 1861; but, with the exception of a monograph on the great nebula in Orion, published in the Philosophical Transactions for 1868, no further account of the observations had been given, and it was time that astronomers should be put in possession of whatever observations had been procured. It was obviously desirable that the original notes of the observers should be pretty fully transcribed in order to give due weight to their evidence. The brighter and more striking objects of Sir John Herschel’s Catalogue of 1833 having been first examined, and the more interesting ones having been ‘delineated in drawings published in the former papers, there remained less scope for the pencil, and the micrometer has been more frequently used instead. However, twenty-five nebulae or groups of nebulae have been figured on four plates, and the new drawings of the crab-nebula Messier 1, of G. C. 1,227 = H. V. 28, and of the spiral nebula Mess. 51, will be considered especially interesting.

The absence of any indication of the places of the nebulae, except in a limited number of cases, is a serious drawback, since it renders constant reference to other publications necessary, and, indeed, gives to the observations a merely supplementary character. It is acknowledged that some difficulty has arisen now and then in regions rich in nebulae in identifying the object observed with a catalogued nebula; but it is believed that very few cases of uncertain identity remain. Into the text have been introduced diagrams, which are rough copies of those drawn at the telescope, and which will be useful in any re-examination, when they can be compared directly with the heavens. In an Appendix some letters are printed in vindication of the performance of the six-foot reflector, against some disparaging remarks which have appeared in a magazine article. Astronomers, however, will probably be guided in their judgment chiefly by the work which has actually been accomplished. The present publication comprises the nebulae between Oh. and 14h. of right ascension; part iii. is intended to contain those within the last ten hours.

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