ASTRONOMICAL NOTES

Hawera & Normanby Star, Volume LXXVII, Issue LXXVII, 24 May 1919, Page 4

ASTRONOMICAL NOTES

THE SUN.

(By L. A. Mac Donald.)

Everyone on the earth must recognise that the sun is the most necessary factor to existence. Nothing that. possesses life in this world, or in the other ftvorlds of the solar system, can live without him. By his life-giving, and sustaining power two thousand millions of human beings and myriads of animals, birds, fishes, plants and. microbes ar© able to live out their little lives in all the habitable portions w-A e, arth > lSea and atmosphere. Uithout the sun th 8 earth would be a. dead planet wandering aimlessly in space. Venus, Mars and Jupiterwould be much the same; all would be m everlasting darkness unless they came within the attraction of some ma6. Si vt llluminiug body. The cold would-be extreme to such an extent that the oceans -would freeze, and no* circulation of water or air currents could possibly take place. To the questions addressed of old to Job. .Hath the rain a father? or who has begotten the drops o f dew, and the hoary frost of heaven, who hath gendered it?" the answer in each cae c «- the sun. H e is the father of the rain and snow of the hail that falls in winter, of the ice which sparkles on the mountain side, and of th e mist which rises from the valleys beneath hte morning rays. It is impossible then to over-estimate the immense importance of the sun in his relation to every rorm of energy and motion -which exists upon the earth.

The sun is very far away: he is much further away than he appears to the eye. He looks no further away jn tne, moon > but his mighty distance reduces his disc to the apparent size ot the earth's satellite. The moon is situate 240,000 miles from th e earth: the sun is situate 92,897,000 miles beyond the orbit of the moon. The vastness of these figures are beyond our imagination. It is not an easy matter to illustrate them by simple facts, > which will make them more or lees comprehensible. Sailors have travelled right round the world; about twentynve of these journeys in a straight «ne if such a thing were possible, would place a traveller in the neighborhood of the moon. With reference to the sun, it would take a fast counnearly a year to count 93,000,000, even if he were to count day and night Suppose a train started from the earth at the 6peed of 30 miles an hour on January 1,. 1919, it would not reach the_sun until the middle of the year 2257. Suppose a man just born were placed m a train going such a journey, and lived three score years and ten, at his death he would only have accomplished one-fifth of the distance. The earth has been, found to weigh six thousand trillions of tons; the sun %veighs one thousand nine hundred and ninety-two quadrillions of tons. Sucn figures are iitterly bewildering to human conception. Little more than a hundred years ago it was thought by many that the sun might be inhabited not on the surface, which was too hot, but somewhere in the darker layers which are revealed in the depth of a sun spot. No astronomers believe anything of the kind to-day. Th e sun is pouring out immense supplies of heat and light. These must be brought np to the surface from within. It must be even hotter inside than on the surface. Between the interior and the surface there must be a continual rush of hot currents bringing up from inside t the heat,which is poured out at the surface. the sun maintains his I heat because he is contracting. A shrinkage of one thousand, feet would supply all the heat the sun radiates > \in five years. At this rate the eun would decrease in diameter about 40 miles in 1000 years. His diameter is 800,000 miles; so it is clear that his heat might be maintained for 100,000 yeafs without any appreciable decrease in his apparent size. During millions of years t.he;sun might be pouring out .his immense supply of heat, year by year, and might all the time be actually growing hotter. The sun 'is thought to be a mass of highly incandescent gas. We do not see the sun himself, but we see the covering of cloud masses which envelop him almost completely. This cloud envelope is called the photosphere. There are bright granulations on the photosphere resembling rice grains. There are spaces between them that are comparatively darker. There are bright streaks in the equatorial regions, which are said to be ridgesl produced by the aggregations of large numbers

of granulations. There are black spots in the same regions that are sometimes over 100,000 otniles, across. One of these great cavities "would hold .Jtnany earths like ours, but they 'would, be burnt to cinders in a very brief time. The spots in different latitudes do not move round the sun at the same paoej at the sun's equator the time is 25f days; at latitude 40 deg. the time is 27 days. Therefore it is believed that the sun does not rotate in one piece. The spots are supposed to be gigantic whirlpools in the photosphere, very similar in nq£ure to the cyclones that distract the terrestrial atmosphere. Where there is intense heat there must be much commotion. In the neverceasing oscillations and vibrations of the interior and of the surface of the sun great outbursts occur from time to time, -which have their analogy on earth in the shapes of cyclones and eruptions. Not being: in the samestage of development the disturbances are exhibited under different conditions, -though the cause is the same. When sun spots are numerous magnetic storms are frequent on the earth, and' beautiful auroras are seen in the sky.

The chromosphere, which is a gaseous envelope surrounding the photosphere, looks like a prairie on fire .a sheet of' ■scarlet flame varying from five to ten thousand miles in height. From this envelope bright scarlet flames, reach up into the sky to a distance of seventy thousand miles. The sight of these flames in the spectroscope can never be forgotten' by those who have seen them. A large portion of humanity has ever looked upon the sun as the visible manifestation of the Deity. Inthe churchyards and cemeteries the inscriptions on the monument® are made to face the east, in sure and certain hope that as the sun rises in the morning from the dark regions of space, so will mankind awaken from the mysterious sleep called death, and pass into another life. The sun is the augustbeing who ascendeth into the heavens in the morning, fmd in the evening hedescendeth into the underworld. He is a creator. pres°r^er __ and destroyer, constituting a trinity in one. His holyday is Sun-day. He is a great conqueror. There are always "wars in the heavens, but he is always the victor. He overcometh the grave of nicht, and" is the resurrection and the life. InTiim we five, move and have our being. "FT" is the litrht that lishteth every man and every living creature into the world—the light of HeMs. And what is more worthy to rec°ive our highest -idmiration and our p"fouT>d obeisance than our great sun—£hat blazing .luminary, whose «leeplec s ev e shuts not ei'Pn to the wind and is for ever gazing on his creatures ? This father whichart in heaven.