THE COMET.

Rangitikei Advocate and Manawatu Argus, Volume XXXII, Issue 8797, 26 April 1907, Page 4

THE COMET.

My attention has been drawn to a Letter published in your issue of the 30th instant, over the signature of the Hon. Director Wangauui Observatory, and although the correspondent begins a little bumptiously, as the commander of a big telescope might be expected to do, I will deal with his remarks seriatim. He says he '' can produce a number [of residents of Wanganui who watched the comet through the medium of the large telescope at the Observatory moving in the field of view among the stars." On the other hand I can produce a resident of Marton, who diligently searched for the comet with tho aid of a good telescope, but saw nothing more than the ordinarv colestial objects. The gentleman declares, in a communication apprising mo of his failure to see it, '' he spent a good while trying to get a sight of it." My own ) experience was attended with no better results. I do not advance these circumstances as an argument against the existence of tho comet. But the Hon. Director appears to I rely on circumstantial evidence to ■ bear out his assertions. Ho does not even state- positively that he saw the comet himself: So, if I am to recognise the validity of the statement that the comet must be there , because his friends saw it, I hope he will be ready to acknowledge the validity of the statement that the comet might not be there because imy friend and myself could not see it. Saying "a number of residents watched it" reminds me of the style , which is not infrequently adopted by a class of storytellers, when they make dissertations concerning the J uninistakeablo appearance of an alleged ghost. In order to expedite matters, the Hon. Director should get the residents to furnish us with a few of tho details of the observations. The nature of the information wo should like to have may be discerned in tho following questions: 1 What was the exact position of the comot, in Right Ascension and Declination, on the evening of the 11th instant? 2. What was its apparent size? 3. What was its magnitude with respect to brilliancy? 4. Whatwas its rate of motion among the stars? 5. What are tho names of some of the stars it passed near to? 6 Why wore no observations taken oil the evening of the 13th and 14th instants? The Hon. Director proceeds to say '' ho cannot understand why I should think Coelurn Sculptoris a most unlikely place." I will endeavour to explain. In the first place Coelurn is a very small constellation. Tho limited space it occupies in the sky is most conspicuously manifost, when the mighty expanse of tho adjoining constellation is surveyed. Take for instance Argo, and Columba, the River Eridaxus and tho Horlogium, and compare the relative sizes of these constellations with that of Coelurn. It only stands to reason that comets spend ' the greater part of their tirno in the largo constellations, and their chances of being soon is tho ratio of the number of times the larger constellations are greater than the . small ones. Again, the position ot Caelum is approximately 40 degrees south Decimation. This is a considerable distance from the Equator; still nioro so from tho Ecliptic. It . is quite true, as the Hon. Director ' says, that '' a comet may appear m auv r.art of the heavens, from either Pole to the Equator." Still their chances of being seen diminish as we i- progress from the. Equator polewards. I have myself observed a come, t and ' a, large one at that, on the Equator, I but I'll venture to say that the Hon. Director has never yet seen a comet in the South Pole, or in the constellation Octavus. However there * is nothing to prevent one from being c there theoretically. But it is another most unlikely place notwithstanding. The Hon. Director assorts that "a comet may move at any angle to the Equator.'' Granted. I will now show how his statement serves to strengthen my position. As comets move at any angle -to tho Equator, their aphelia must neces- ■ sarily bo scattered over a very large area of the sky, while their perihelia, no matter what the inclination of their orbits may be, remain restricted to the immediate neighbourhood of the sun. This is why comets are generally seen in the Zodiacal T constellation, and on the border of J the twilight. .That any given comet will come into a Zodiacal constellaS tion is certain but that any given comet will approach a certain polar, or intermediate constellatin, is uncertain. In conclusion, I think I have demonstrated that I have some justification for "calling Coelurn an unlikely place. Its smallness alone would militate against its chance of receiving a comet. My former article was the result of no hasty conclusion. I scrutinized the heavens carefully for two nights without success. Perhaps my telescope, which is a Sin. reflector, was not powerful enough to reveal the comet. ■ Mr G-rigg's, presumably, is a 3in. } reflector, similar to that of the gentleman in MartoD. Will tho Hon. Director kindly inform mo whether he knows for a fact that the astronomers in Great Britain and on tho Continent are now following the comet in their skies. In England, the constellation Coelurn is never far above the horizon, and the comet may be losing light as it travels northwards. On the other hand if the comet bo gaining m brightness, how is it that it should be lost sight of so easily hero. L. A. MacDOHALD, F.RG.S. [We publish Mr MacDonald's letter, but regret the tOno of childish petulance and unworthy quibbling he has seen fit to adopt. ]