GLORY OF THE STARS.

New Zealand Herald, Volume LXII, Issue 19086, 3 August 1925, Page 7

GLORY OF THE STARS.

THE HEAVENS IN AUGUST. PLANETS AND CONSTELLATIONS. (By tho Hon. Director, Wangjanui , Observatory.) The sun I°. in the constellation Cancer until August 8 > when ho moves into Leo, in which he will have his path during tho rest of tho month. His northern declination decreases during tho month by rather more than nine degrees and his altitude at all places in Now Zealand will be so much greater at noon, during this period. Sun spots have been fairly in evidence during tho past month, a fine group being visible in northern solar latitude at time of writing. Tho partial eclipse of July 21 was seen very well at this station, clear skies prevailing throughout. The moon, moving might by night toward the east, passes the planets and some of the brighter stars, and serves as a convenient pointer to them. She will be nearest Jupiter on the evening of tho 3rd; Uranus, on tho civening of the 7th; Mercury, on the evening of the 20th; Mars, on the srvie evening; Venus, on tho evening of the 22nd; and Saturn, on the evening of the 25th. There will be a partial eclipso of the moon on the night of itho sth. Tho moon will enter the umbral shadow at 9hr. 57m in., middlo of the eclipse at llhr. I2rain., and leaves the true shadow at 12hr. 47min. About 75 per cent, of tho moon will be in the earth's shadow at central phase. Mercury is an evening star at the beginning and early part of tho month. He will become stationary among the stars on tho 11th, and will bo between the sun and the earth on tho 25th, after which ho will emerge as a morning star. He will bo in lunar conjunction on the afternoon of the 20th. Jewels la tbo Evening Star. Venus is an evening star now very conspicuous in the western sky at sunset. She will be in lunar conjunction on the evening of the 22nd. Viewed in the telescope, she presents the phase of the moon nearly full as she is considerably beyond the sun's place at this time from which position she is approaching the earth, till the end of November, when she will be at her greatest elongation from tho sun, and at her (most interesting phase. Mars is an evening star during the month but getting very near the sun's place in the heavens. This time last year, it will be remembered, we were looking to view Mars on the meridian at midnight, in the month of August, now tho planet is on the other side of the sun. Next year again we shall have him in our.night skies but farther away than in 1924. He will be in lunar conjuncton on the 20th. Jupiter is an evening star, visible at sunset rising in the eastern, as Venus sets in the western sky. Ho is finely placed for telescopic study at this time; his "belts" being full of changing forms and markings most varied. He will be in lunar conjunction on the morning of the 3rd, but near the anoon on thi6 and the preceding evening. The most favourable evenings for observing the eclipses, occultations, and transits of his brighter moons, will bo the 4th, sth, 7th, 11th, 13th, 14th, 18th, 20th, 21st, 22, nd, 25th, 28th. Saturn is an evening star throughout the month. His fine ring-system is now well placed for telescopic observation. He will be In lunar conjunction on the evening of the 25th. Places o2 Constellations The constellations miy be seen as giveu below at 9 p.m. of the Ist, Bp.m. oi the 15th, and 7 p.m. of fihe 30th of the month. Looking north we can see Hercules and Lyra on either side the meridian, nearest the horizon. v The brilliant yega, in Lyra, is a very fine star ol! the bluish-white tint, which, signifies one having a very high temperature. Jlist to the east of Lyra wt> see Gygnus, the Swan, his foremost star, Beta (Albires), being a very fine | double. Over thesß lie Aquila east and Ophiuchus and Serpens to the west of the northern meridian, the littlo Dolphin J being east again of the Swan. Pegasus is rising north oi east, and oyer the eastern point may bo seen Aquarius, well up, with Capricornns and Sagittarius reaching up to the point overhead. Cetus is just making its appearance south of east, while Phoenix and part of Eridanns, with the brilliant Achernar, may be seen Over the south-east. Canapus is low down, near the southern meridian, tho rest of the fine stars in Argo lying to the right, and Hyrdus, the Toucan and Pavo to the east of the southern meridian. Tho two Clouds of Magellan are east of the southern meridian. Looking west we find Virgo near the horizon, it:} fine star Spica bringing this constellation into, prominence, while nearing its. setting in the northwest is Bootes, and its brilliant Arcturus, with the Northern Grown. The Southern Cross ia * now getting well over in the western sky followed by the Pointers and the Southern Triangle. The rest of the stajra of tho Centaur, with Libra and the Scorpion, are all in the western section of the heaveaf) at this timo, Neiw Stars. The new star in Pictor, or Nova Pictoris as it will bo known, is not following the ordinary course of these bodies, that blaze up' suddenly and then rather rapidly and steadily decline. The new / star has risen, ia tne last week or so, to more than a magnitude brighter than it was. This kind of variation presents a problem that is very far from being solved. It appears that we have in these stars a change, or a series of changes, in the temperature of which 'lre can form no conception. In some instances it may reach tho theoretical amount of 50,000 degrees. If there is anything approaching such tremendous heat as this then the theories of Kalm and Disslandres, especially the latter, may be seriously concerned in the processes. It may, indeed, be taking place in that body we see every clear evening lying between the bright star Oanopus and tho Pole. In this celestial crucible, elements of a complex order may be rapidly broken up and converted into simpler ones, such as hydrogen, helium, and others of which we know as yet very little or nothing. The disruptive effects of such temperatures upon matter that had, perhaps, reached a condition of approximate rigidity would be immense. The series ot waves of greater brilliancy which break upon our vision may be the result of layer upon layer of super-heated material being torn av»'ay from the parent mass, and rolling ou£ in great shells of escaping molecular masses to bo dissipated Into spaco. Varying Density of Resistance. But what is tho originating cause of such a cataclysm, or a series of them ? It would seem that a collision of some kind must be postulated. If it were not for the evidence of a more or less uniform material entering into tho composition of aU celestial bodies, one might postulate a sudden blending, or a series in which the materials were as match to gunpowder, magnified a thousandfold, 'or many times such state of liberation as occurs within our terrestrial experience. Professor Bickerton's theory of grazing impact and tho formation of a third body, rapidly expanding and being dissipated into space by the tremendous velocities of its particles, is a feasible explanation for a sudden rise and a rapid and orderly decline, but here we have something which suggests changes, of a different order. In chemical reactions there are variations of great magnitude, duo to temperatures of different orders. We have seen a meteor enter the atmosphere of the earth, and register such changes through friction. In such cases, we often note tho explosive action produces apparent differences of great magnitude in the brilliant masses thrown off. A dark .star plunging through a cloud of cosmic matter, at great velocity, in our direction, might meet masses of varying density within the cloud of non-luminous material and in its meteor-like flight would rise and fall in brilliancy according to the variation in the resistance of the different regions through which it passed.