THE SOLAR SYSTEM.

Lyttelton Times, Volume CXV, Issue 16493, 7 March 1914, Page 16

THE SOLAR SYSTEM.

Six Lectures given ty R, A PROCTOR during the month of January, 1874, in tho United States. TITLES: 1. “THE SUN,” Part I. 2. “ THE SUN,” Part 11. • 8. “ THE SUN’S FAMILY OF PLANETS,” Part I. 4. “THE SUN’S FAMILY OF PLANETS,” Part IT. 5. “COMETS AND METEORS.” G. “THE MOON.” The Lectures are copied, revisod and brought up-to-date by his daughter, MISS MARY PROCTOR, nnd now are re-published for the first time. [All Rights Reserved.] THE MOON. Wlion I dealt with the subject of the sun, I spoke of the worshippers of the sun, who knelt down to him nnd regarded him ns the ruler of their destinies, but there wero nations who worshipped the moon, and, if we inquire into the reason of such worship we very readily find it. We notico that Job speaks of the moon as “walking” in brightness, and ho speaks, too of the worship of the moon. Tho ancients worshipped any body that seemed to move upon tho heavens, and therefore they worshipped the sun, the moon, and tho planets. Now this orb that moves around tho earth seems to be there in order to give light during the night time. Let us see what astronomy has taught us. It teaches us that tho moon is very much smaller than tho earth, with a diameter of 2160 miles. She is distant from the earth 238,840 miles. The surface of the moon is less than the earth’s in the proportion of 1 to 13. In other words, the surface of the moon is about 14,600.000 square miles, equal almost exactly to the surface of North and South America. It is also equal approximately to the surface of Europe and Africa taken together. If the moon is the abode of life there is plenty of room for life there, and it is an interesting question whether she can now maintain life. We know r that the volume of tho moon is to that of the earth as one is to forty-nine, that is, it would take forty-nine halls, each as large as tho moon in bulk, to make a ball of tho size of the earth. Her density is rather less than that of the earth, so that her mass is to the earth as about 1 to 81. OFFICES OF THE MOON. First of all, as to the offices of the moon. If it is shown that she discharges important offices to the earth, you will sec that we are no longer bound by the argument of design to recognise her as the abode of life. First, we know she serves for the division of time. She gives light by night, and the service is so regular as to suggest that it was intended for that special purpose. Laplace went so far as to say that if he had tho direction of the moon, lie would havo made it much more useful for man. He would have put it four times its present distance away from tho earth, when it would he far enough away to be a full moon and give a regular light shining continuously hv night. The first objection to this is an astronomical one, for moonlight would very much interfere with observations of the stars, nebulas or some barely visible comet. lam surprised, indeed, that Laplace, himself an astronomer, should have suggested so inconvenient an arrangement as that. But there are other difficulties. If the moon was in that position she would always have to be opposite the 6wn. Tho moon would no longer be a measure of time, nor would she rule the tides. She now raises a great wave called the tidal wave, represented in Height by 5. You havo another caused by the sun, represented by 2. These two waves are sometimes combined in it single wave, and act together, sometimes opposing, sometimes coalescing. According to these changes, the tide varies in height from the difference of 5 and 2. to the sum of 5 and 2. That is to say, 3 the least height, and 7 the greatest.

This is a very important matter. It is of great service, as anyone who lives by the seashore realises, it is also of groat interest to the shipbuilder and merchant that there should be variable tides, nnd that there should not always be high tides, nor always low. That important service would not have been rendered by the moon if the consideration suggested hv Laplace had prevailed. There is another very important lunar service. The moon enables the astronomer or seaman in long voyages to ascertain the longitude, which is nothing move or less than the true time at the observer’s station. Tf she moved twelve times more slowly, sho would bo loss fit to indicate the time in exactly the same degree as tho hour hand of a watch is less fit than the minute hand. There are other very great and important advantages of tho real moon over that suggested by Laplace, which I wonder did not occur to a mathematician such ns he, the only man who ever lived, of whom it can be said: “Ho was the rival of Newton.” He, himself, said Newton was fortunate in having lived before him. Tn another man it would have been considered rank conceit, but in Laplace it was considered as a just statement. Yet he failed to notice, when ho suggested this moon being four times further from us, that under these conditions the light given would be lessened. TELESCOPIC VIEWS.—THE MOON HOAX.

I pass from these considerations to the telescopic study of the moon. When we think how near the moon is, tho planet that comes nearest to us being 130 times further away than tho moon, certainly the hope would 6eem natural when Galileo first turned his telescope to the moon that he would discover signs of its fitness to be tho abode of life. We know what happened. He found there a surface covered with mountains, which he compared in number to the “'eyes” on a peacock’s tail. Where there appeared to be dark surfaces of a level nature, he called them seas.

Telescopic observations went on, and all that was found was the gradual enlargement of these features, and the revelation of new details, but nothing to suggest that life existed on that arid surface. Men went on hoping that with telescopes of increased size moro results would be obtained. It was thought that with Herschel’s great telescope something more might be determined. Herschel thought he could recognise in the bright part of the moon signs of volcanic action, because he saw a faint light as of volcanic origin. We know new that it was only tho reflection of the light of the earth.

About this time, Mr Locke, an American, published in the New York “ Sun,” the Moon Hoax, which misled not only the ignorant but. those who were well educated. Great ingenuity was displayed in the method of its construction. An account was given of an imaginary conversation between Sir David'Brewster and Sir John Kersckel, and the enthusiasm of Brewster is very comically described, as he leaps from his seat, and catching Herschel by the hand, exclaims: “ Thou art the man !” Then follows an account of animals on the moon, which seemed to escape whenever the observer tried to fix his attention upon them. A comparison was made between monstrous creatures, termed the Bat-men and the militia of London. At this point the story seoms too absurd for belief, yet we can imagine the impression it made, ( when some ono wrote to Sir John Her-

sohel from America, asking if it was true, and urging means of conveying instruction to the poor benighted inhabitants of the moon. I saw a few days ago (1874) in an American paper an idea based on the same mistako that existed in that Moon Hoax, only there it was not a mistake but a trick. If you have the image of the moon photographed to perfection, it seemed as though you might magnify that image by the microscope, and see objects of half a mile or less in size, if not recognise living creatures. But this is the same mistake as those make who believe in the transfusion of light. What the astronomer does when ho sees the moon through a telescope, or when he takes a photograph of the moon, is to magnify the image as much as it will bear. If he interposes a screen and tries to magnify the image, he is magnifying a moon less perfect. There is a limit in the telescope beyond which it cannot bo increased. Tho optical imago formed by the object glass of the astronomer has dofocts, and if you magnify it you magnify the defects. When you get beyond a certain point it is useless. to magnify the image. (The great Lick telescope of 36 inches aperture, with a power of 2500 or so. may possibly reduce the actual distance of tho moon to about 100 miles for visual purposes. It is evident that while with our telescopes we should bo able to see such objects as lakes, rivers, forests and great cities, if they exist- on the moon, it will be hopeless to expert to- distinguish single buildings, or any of the ordinary operations and indications of life, if such there are—M.P.). EVIDENCES OF ABSENCE OF ATMOSPHERE.

When we begin to inquire into the characteristics of the moon, we see how hopeless it is to expect signs of life. Wo have an orb without any atmosphere, or a very shallow ono. This is shown by the fact that the shadows thrown by the lunar mountains are black and sharply defined. An observer watching our earth from the moon would not see black shadows but dark shadows, blending with a certain amount of light or twilight. Those who have watched the sun at dawn from the top of a lofty mountain know that when the summit of the mountain is bathed in the full glory of sunlight, the sides of the mountain are still in shadow, and the neighbouring valleys are plunged in a yet deeper gloom, but the lights and shadows nro blended, in twilight.. On the moon no half lights are visible and as a result the bright blaze of sunlight illuminating the mountain heights is sharply contrasted with the intense blackness in the valley below. This explains the points of light which can be seen apparently detached from tho crescent, but they are in reality sunlit mountain peaks, or a lofty ridge of cliffs, surrounding a lunar crater or extinct volcano, of which there are thousands on the moon. Tho blackness of the lunar shadows shows that there is no.illuminatecl sky such as ours, and this is the first proof that the moou has no atmosphere. On our earth, as you know, there is a twilight surface extending to a very great distance, which divides true sunlight from the place where it is night, but on the moon there is no twilight surface whatever. Look at the earth from the moon, at the time of “new” earth, when tho earth is between tho sun and the moon, and there would be seen all around tho disc of the earth this twilight. We, as you know, on the contrary, when we have a full moon, see the edges sharply defined, with no extension on either side by twilight surface. This is a second proof, and the third proof is when the moon passes over a star. The star retains its full brightness until it reaches the edge of the moon, when all at once, without the least warning, it simply is not, there. Tho disappearance is absolutely instantaneous, and the re-appearance still more startling. Now, if*the moon ha<J any perceptible atmosphere the disappearance would be gradual. The star would change colour, become distorted, and fade away more or less gradually. These are three convincing proofs that the moon has no appreciable atmosphere. If the moon has no atmosphere there can be no life such as we know. There may be life of other forms inconceivable, and it would be idle to inquire what they may he. 1 believe there is no life on tho moon. I. find a limit to where life is on our earth. We may say tho conditions on our earth are not the same throughout—greater or less light, more or less moisture—but we find that those conditions really limit life on the earth. Beyond a certain'height on the mountains there is no life, or existence at high levels is trying, but so far as analogy teaches us there can be no life where there is an absence of atmosphere, so we must believe there is no life"on the moon. THE SEAS OF THE MOON. Besides a lack of atmosphere there is no sign of water on the moon, though there may have been at ono time. The signs of past- volcanic action in the moon are due to volcanic eruptions, and there must have been water on the surface. What has become of the water? Various theories have been advanced, such ns the ono suggested by Whiston, that a comet carried away the lunar oceans and atmosphere. We give that up at once, for wo know that while the moon might get something from tho comet, no comet could draw anything from the moon. Another explanation is that the lunar oceans of former times have boon withdrawn into the substance of tho moon. There are many things in the moon’s appearance that seem to indicate the former existence of sens and oceans on her surface, and it is not impossible, or even improbable, that solid water, that is, ice and snow, may exist on tho moon’s surface at a temperature too low for any sensible evaporation.

THE PHOTOGR APHIC STUDY OF THE MOON.

A photographic study of the moon was begun by Dr AY. 11. Draper, of America, in 1840, and that work greatly increased in perfection. Mr Do La Rue, of England, obtained a mastery of photography, but Mr Rutherford, of Now York, obtained photographs which De La Rue frankly acknowledged were better than his own. (Rutherford’s pictures have remained unrivalled until very recently. Howover, since 1885, great progress has been made. Tho Lick and Yerkes observatories have obtained admirable results, and a complete atlas of the moon lias been made at Paris. The Paris atlas is especially fine, shewing the features on. various scales corresponding to lunar diameters ranging from four to nine feet. But the photograph cannot yet rival tho eye in the study of dedicate details.—M.P.)

LUNAR SCENERY. Photographs of the full moon show its surface brightly illuminated, with a blending of lights and shadows, and vague outlines denoting lunar seas and plains, but the wonderful crater called Tycho, with a nearby region where crater overlaps crater, can be clearly distinguished. Over thirty thousand craters have been mapped by Dr Schmidt, of Athens, and others, so that it is possible to com para these maps with others taken more recently, for the purpose of detecting any changes which may be taking placo in the moon’s surface. A dark round spot called Plato, seemed to show evidence of the kind. It looks very dark indeed at tho time of gibbous moon, and examined through a telescope, it is found that it looks lighter at the time of tho quarters than at the tinio of full moon when brightly illuminated. Now, it has been suggest-.

ed that on that spot some process of vegetation is taking place there. Unfortunately, it happens that there ia also a strong argument against the theory that there has been any real change there. In contrast with the shadows thrown at tho time of the quarters, the floor of Plato naturally looks brighter, whereas in the case of the full moon, all around it is a brightly illuminated region. The mountains have a great illuminating power, and therefore by contrast Plato looks dark, but this is merely a subjective effect, and we have not the evidence we looked for. (Professor W. H. Pickering considers that his observations and photographs of 1902-1903 show changes upon tho moon’s surface, which indicate the deposition of snow or hoarfrost at certain points during the lunar night, and its subsequent disappearance when the sun’s rays reach it; very much as if a subdued volcanic activity still persisted in the moon with the vapours issuing from beneath through fissures and fumaroles as at Rotorua and Geyser Valley, but as yet his views do not seem to have gained general acceptance.—M.P.).

The moon’s surface is covered with irregularities, indicating volcanic eruptions in the past. These are caused by the gradual contraction of the outer crust of the earth, gases are generated and these gases escape out of the mouth of the volcano. If such processes have taken place on the moon, they must have been much more violent and on a more extensive scale. It was suggested by Dr Hook that in a former state of existence there was a bubbling of the plastic surface, and as the bubbles broke, these circular openings were formed. (The mud volcanoes at Whalen and Geyser Valley are a splendid illustration, showing a marked resemblance to the pitted surface of the moon.—M.P.). METEORIC THEORY.

We seem forced to adopt a very startling theory, namely, a pounding down of meteoric missiles, not necessarily solid ones, but a falling down of meteors on the plastic surface. It seems to me that is the only theory left. At the present dav it is estimated that over 400,000,000 meteors fall through tho day, but the result is very slight indeed. When wo look back upon, the past history of our system, wo see signs of a time when larger meteors and more splendid comets were at hand to be absorbed in the solar system. While the earth was still in a form of vaporous matter, tho moon was rolling on, still plastic and those meteors falling down upon her surface would produce the pitted appearance. THE MOON, A DEAD WORLD. Those lectures have shown how in the solar system are to he found the signs of a beginning and an end. Jupiter and Saturn have made progress to a state further than the 6un, but are still full of life niid energy'. Then in the progression comes our earth and Mars, Mercury and Venus, which have lost most of their inherent heat,.. In the mooh we have a body seeming to liavo lost all its inherent heat, and to have neither water nor air. All these signs of progression seem to point to the day of creation, and teach us to look forward to the time when these processes began. There must have been a beginning of these processes in the moon. Looking forward we see that our sun, the youngest as it were, so far as signs of passing on to old ago are concerned, will one day lose heat and all the planets in the solar system will have lost theirs. The moon has long since passed the time when it was fit to he the abode of life. Jupiter and Saturn have not reached the time, but for all that there may be millions of planets circling around the stars in space, and many of them inhabited. Tims we are rid of the painful thought that our insignificant planet is the only one inhabited in the entire universe. Wo can address the Creator in the language of the poet:— “God of the prranite and tlie rose, Soul of the sparrow and the bee; Tho mighty tido of being flows Through countless channels. Lord, to Thee. If leaps to life in gi-a.es and flowers, Through every grade of being runs, While from creation’s radiant towers Its glories flame in stars and suns."