THE TRANSIT OF VENUS.

Otago Daily Times, Issue 6497, 8 December 1882, Page 2

THE TRANSIT OF VENUS.

Our contributor "Acher Nahr," who observed the transit at Purakanui yesterday morning, forwards the following notes : —

Sky completely overcast with dense cirrostratus clouds, which completely obscured the Sun's disc, rendering any attempt at observing middle of transit nugatory. A break in the clouds rendered it possible to observe Venus well defined oh Sun, intensely black, and surrounded by_ slight halo. Definition not first-class, but still far from bad. _ Venus, its own diameter distance from Suns limb, definition generally somewhat improving. Venus well defined on Sun's disc; atmosphere or halo still very apparent. First internal geometric contact of limbs at egress, no distortion of the limb of Venus, or appearance of black drop whatever. Black ligament contact perfect; black ligament meaning iii this instance where Sun's limb appeared completely broken away by Venus. . '. ■ . Venus, its own semi-diameter across the Sun's limb; external contact at egress, no appearance of ligament; Sun's limb assumed its normal appearance. Daring the whole of the preceding observations, tho Sun was '.:> a, certain extent maskad by a thin film of cloud, not sufficient to render the task of observation difficult—in fact, rather the reverse, inasmuch as the use of a lighter darkhead on the telescope was possible. Tho telescope used is a 3Jui. equatorial;_ the power employed, 150 diameters;, with light neutral-tint darkhead of. sufficient intensity to prevent any pain to the eye, and .at the same time enable the object under view to be critically and accurately examined. Its potver in separating double stars is good—instance, 52 Orionis. The granular structure of the Sun was distinctly visible. MR GILLIES1 OBSERVATION. : Mr Robert Gillies was very successful in his observation, the internal contact at egress being remarkably distinct. It came on very gradually, the line of light getting thinner and thinner. The weather was all that could be desired about ■ the time of the contact, though about half an hour before nothing could be seen of the Sun, which had not been visible during tho forraer.part of the morning. The external contact was not quite so clear, but Mr Gillies made a very good observation of this also. MKSSRS BOSS AND SKKY'S OBSERVATION. At the observatory on the Town Belt Messrs Ross and Skey obtained a capital view of tho transit. From a quarter to i until twenty minutes past 0 there seemed to bo no hope of a useful view of the transit, but the Sun emerged from the clouds and remained clear until about two minutes after the external contact had been completed. During the critical time, from a little before the internal contact until the transit was made, a splendid view of the Sun's disc was obtained. There was a very fine fUm'of cloud over the face of the Sun, but this, far from interfering with the observation, caused a better definition to be obtained, the limbs of the Sun and the planet being well defined. Mr Beverly's observation. Mr Arthur Beverly has furnished our evening contemporary with the following:—" At an early hour this morning the prospect looked rather gloomy for the Dunedin observers of tho transit; but, as the critical time approached, the clouds cleared away and left the Sun shining through a faint haze in the upper at--mosphere. This haze improved the definition wonderfully, for, when it cleared away a few minutes before external contact, the outline of the Sun, which was previously sharp and steady, began to flicker slightly. The haze also reduced the irradiation nearly to zero, so that there was no appearance of black drop, or any of those perplexing phenomena_ which occur at internal contact when the sky is clear. Altogether the weather could hardly have been better if got up for the occasion. The disc of Venus while on the sun appeared very sharply defined, and as it approached the edge of the sun the luminous line separating them became finer and finer, until it vanished at the point of contact. This was not a prolonged affair, as we were led to expect; the breaking of the luminous thread was so sudden that there could hardly be a mistake of two seconds in recording it. In about 10 seconds after contact the only other phenomenon worth mentioning began to appear. The part of Venus which projected beyond the Sun's disc showed a very fine pink outline, causoid no doubt by sunlight refracted through her atmosphere, which continued visible until the disc of Venus ! projected about a fifth of its diameter beyond the solar disc. It then gave way at the north side, but continued visible at the south side until Venus was half off, when it appeared like a minute pink hair standing perpendicular t» the Sun's margin at tho edge of tho semicircular notch. The times of contact as observed approximately were—lnternal, 7h. 31m. ; external, 7h. film. New Zealand mean time, or about 10 lninjitcs later than the times given in the 'Nautical Almanac' How such a blunder could havo boon made by the conductors of that publication it is not easy to see,"

DR HECTOR'S OBSERVATION. Clyde, 10.37 a.m. The morning was overcast. The clouds only broke ten minutes before internal contact, and the sun was again obscured by a small detached cloud about one minute before the critical time, and did not emerge till three minutes after. The sun's edge was very sharp, and a good observation would have been possible but for the clouds. Mr Ward, postmaster, Cromwell, got time of contact, but only with a small telescope.

(Per United Press Association.) Auckland, December 7th. The American observation party report that the observations of tho .transit this morning were very successful. Seventy-four photographs were taken up to tho time of the internal contact, when a thin haze of clouds prevented further photographs. They then had recourse to the telescopes, and observed tho planet up to the timfi of the external contact, tho clouojs not interfering with telescopic observations. The observers say that. they have never seen such successful results. The photographs will be sent to America by the next outward steamer, and by tho one following, to prevent accidents. The party then go to Sydney for the purpose of continuing pendulum operations.

Wellington, December 7th.

* A superb morning broke on this eventful dute of the long-lookod-for transit of Venus. Hardly .". cloud was to be sceii or a breath of wind felt when the Sun first rose. There was, as there had been all night, a good deal of that atmospheric disturbance known as " boiling," which caused the solar disc at times almost to resetnble^a circular saw, and rendered all precision of definition impossible, but as the morning wore on thi3 passed away, and there was. at the critical moment perfect stillness and definition. The dark body of the planet could plainly be seen, even with the naked eye protected by a smoked glass, as the Sun rose, and it remained visible to the end. Just before egress some light fleecy clouds passed eastward, causing apprehension lest at the supremo instant of internal contact the observation should thus be marred. Fortunately the fear proved groundless, the clouds passed by, and at the time of coutaet the clearness and stillness could hardly have been better. By 7.53 a.m. all was over, and it only remained to compute and compare results. The success of the New Zealand observations was almost complete. Colonel Tupman, at Burnham ;Mr M'Kerrow and Mr Adams, at Mount Cook, Wellington ; the Yen. Archdeacon Stock and Mr King, at Tliorndon, Wellington; Mr Shannon and Mr Littlejohn, Wellington ; Mr Marchaut and Captain Hewitt, at Wairarapa ; Mr Humphries, at New Plymouth ; and Professors Smith and Pritchard, of the American observing party, at Auckland—all report thoroughly satisfactory observations of Both tho internal and external egress contact. Tho American. party, moreover, have baon successful in taking no fewer than 75 splendid photographs of tho transit. Mr W. B. Gibbs, of Wellington, has taken several excellent photographs of tho phenomenon in its different stagos, It would hardly be possible for more perfect accomplishment to have been achieved of the aspiration of so many years than that which has on this occasion rewarded New Zealand observers. The only failure among the mow important observations was that of Dr Hector,_ at Clyde, Otago, whoso view was vexatiously intercepted by a dense cloud almost at the very instant of contact. There are, however, ample complete observations for all the purposes aimed at.

CHiusTCia'KCH, December 7th. Colonel Tupman is well pleased with his work iit Burnham. Ho hail two telescopes going— -ono worked by himself, with tho aid of Mrs Tupmnn and Mrs Cell, who was in charge* of the galvanometer; the o,ther superintended by Lieut, and Mrs Coke, aided by Mr White, telegraphist. On comparing notes it was observed that wonderfully similar observations had beon taken.

TniAitu, December 7th. Tho shy was too cloudy this morning to cnabio Archdeacon Harper. to obsorvo tljo transit, of Venus.

|By Electric Telegraph.—Copyright.] (Reutkr's Telegrams.) Melbourne, December 7th. (Received December 7th, 1882, at 2 p.m.) The observation of the transit of Venus torn the Melbourne station was successful. It -was Homewhat cloudy at sunrise, but the clouds cleared off before the critical time. Twentythree good photographs were obtained.. The observations at the Gippsland station were not successful. The weather was misty, and rain was falling. Brisbank, December 7th. (Received December 7th, 1832, at 9 p in.) The intended observations of_ the transit of Venus were rendered impracticable by bad weather. Heavy rain fell both liore and at .Titnbour, and the English astronomers did not succeed in taking any observations. Sydney, December 7th. (Received December 7th, 1832, a', 0 p.m.) ' Rain fell here this morning, and heavy clouds prevented the observation of the transit of Venus. HortART, December 7th. (deceived December 7th, 1832, at 9 p.m.) The observations of the transit of Venus were completely successful this morning. The weather was' very favourable, and the observers consider the results perfect throughout.

(Special to I'bess Association.) London, December 7th, 5.45 p.m. (Received December 7th, 1882, at 10.30 p.m.) Very successful observations of the transit were obtained in America, Cape Town, Durban, and the West of England. At Paris and Madrid the weather was cloudy, and prevented the contact being distinctly observed. The transit was plainly visible at Cork, but at other stations in Ireland the sky was overcast.

In connection with the transit of Venus, Colonel Tnpman has succeeded in determining the exact lonjitude of the chief towns of New Zealand by means of telegraphic signals flashed from the Sydney Observatory to Burnham, and rice versa: Dr Lemon, superintendent of New Zealand Telegraphs, deserves the greatest credit for the complete telegraphic arrangements made, and the means devised for the perfect receipt of the signals. - The difficulty which attended the undertaking may be better understood ■ when we remember that an ordinary message forwarded to, Sydney undergoes four transmissions—viz., Christchurch to Blenheim, Blenheim to Wakapuaka, Wakapuaka to La Perouse, and La Perouse to.Sydney; but as in this instance the exact lo'ngitudo was required, and not the approximate, as previously determined it was necessary that the whole, should form one complete circuit, so that signals could be sent direct from the Sydney Observatory to that at Burnham. The total length of line in circuit w*as therefore 1700 miles, the longest ever signalled upon in the Southern Hemisphere. The battery power had to be limited to 15 cells (a little more than a third of the power used to work from Christchurch to Blenheim), lest the Australian cable should be injured. The signals were received on a very delicate "Thompson reflecting galvanometer, the current passing through, the instrument being equal to l-1500th part of an ordinary Darnell's cell. The signalling_ was most suc-cessful,-being received to within a small frac-, tion of a second.' MrShaploy, chief electrician of the Australian-New Zealand cable, manipulated the instrument at Sydney, and Mr Gill, of Wellington, was specially deputed by Dr Lemon to carry out the duties at Bitvnham. — Christchurch Press.