PLANTARY CALL

Evening Post, Volume CXXVII, Issue 117, 20 May 1939, Page 16

PLANTARY CALL

MARS COMES CLOSE

MYSTERY OF THE CANALS

■:" JYom now on, for a few weeks, the planet Mars will be a celestial object of .increasing, interest,, . It is rapidly approaching the time, when. it will be •fiii opposition. on July 23, which is an astronomical..term. to. express the fact that the planet will be taking up such a position in...the heavens., relative to .the. earth and sun, -as will,involve it coming as close to. the earth as the laws which govern the movement of heavenly .bodies permit. In a few weeks' time Mars will be only a mere $5,000,000 miles from the ;earih, whereas at other times when in opposition it is as far as 63,000,000 miles away, owing to the fact that its orbit is very elliptical. The planet is now very favourably placed in. the heavens for Southern Hemisphere observation, and is a very bright object in the evening sky. There is.nb mistaking its lurid fiery red glow, which contrasts markedly with the whiteness of Venus or Jupiter, and by the "end of June it will be- brighter - than"" Sirius Ofche bright star known to even the mo§t casual of observers of the heavens) and quite as" bright as Jupiter.

TThe planet Mars .has always had a special -fascination for .„ earth-dwellers, and it has. been the subject of more speculation and has figured more often in fiction than any other planet. Does it contain life as we know life on earth?. Is. it.peopled by a race of supermen, far more intelligent than ourselves? Are the so-called "canals" seen on its-surface the work of men or their Martian 4 equivalent?

'."■ Before considering the possibility of answering such questions, it may be as well to state a few facts about Mars before entering the realms of speculation. Mars is the fourth planet from the sun, and occupies the next orbit outside that of the earth. Of all the planets it is most favourably situated for observation from the earth. True it is that Venus sometimes comes closer than Mars ever does, but when

does this she is bashful and turns away her illuminated face, hence astronomical observation is abortive. But when- Mars, every 2\ years or so, "approaches the earth the disc is fully illuminated by the sun and large telescopes ; 'can reveal quite a number of unusual and interesting features. Mars lias a diameter of about 4000 miles — aisput half ihs^of' the earth. ' Almost certainly it has an atmosphere, but of What gases tins is composed is uncertain. Its temperatures are reckoned to be comparable to those prevailing on "the earth, but probably colder. Mars, it is agreed by astronomers, has very little if any cloud, and therefore no fain. It would enjoy perpetual fine weather, with seasons similar to ours, but each lasting about twice as long, since Mars takes a'little over two of our years to complete one' revolution round the sun. MUCH-DEBATED CANALS, But it is the curious and unique markings on Mars revealed by the telescope that are of such interest to both professional and lay astronomers. Telescopes" reveal on the surface of Mars ah irregular greenish-blue area dovering about three^eighths of the total surface. Most of this' lies south of the Martian equator, although in one place there is a considerable projection to the north. This dark area is permanent, although it undergoes periodical changes. . From these dark areas running into the brighter parts of the planet's surface are> filaments, or so.they appear to telescopic vision, and these filaments form a network over the planet. The poles of the planet are white, and at certain seasons of the year these white areas contract. When this happens, changes are seen in the dark areas and in the network of filaments. Here, then, are the essential elements of the Martian mystery. To solve it, put two and two together.; but the answer, although decidedly intriguing, still belongs'entirely-to the realm of speculation. Briefly it is that Mars is a dying world, that it is drying up. The while poles are covered with snow, like the earth's poles. When this snow melts in the summer time, the Martians see . it that the water runs along the irrigation canals which they have constructed in all' directions to the dark patches. These dark patches axe where the vegetation still grows arid presumably where the Martians still live, although no telescope is as yet big enough to pick up the Martian State houses. A" pretty theory this, to be believed of not according to inclination. Professor G. V. Schiaparelli started it in 1677 when he first called the fine fila-ment-like lines observed oh Mars canals. He maintained that these canals appeared to double at certain seasons, that is when the snow at the pples melted and the water flowed along theni. The "doubling was due to the growth of vegetation along the canal sides. In the same way the seasonal changes observed in the dark areas on Mars were due to vegetational changes as ths water supply increased. All observers, however, asz not agreed upon the doubling of the canals as deScribed by Schiaparelli, but all are agreed that there are seasonal changes in the dark-areas.- ? ■':-•; A POPULA^T'tHEpfeY. Professor Lowell- subsequently popularised the canal theory* ■• and even ■went so far as to postulate the theory, that the canals must be the work of intelligent beings owing to-their geometrical formation. He apparently overlooked the fact that, geometry plays a very large part in the formation of the universe under conditions entirely excluding the co-operation of intelligent beings like man. As a matter of fact the so-called canals, some of which are three or four hundred miles long and about fifty broad, are not as geometrically regular as they are sometimes drawn. The accompanying photograph shows these canals as drawn by, competent astronomers at the-famous Lick' Observatory, hundreds of -photographs and Observations having been combined =to make the draw-

ing. ;•" ;;""^ ? '■ However, Martian's "and'their canals fcave always appealed widely to popular imagination since they were fire*

postulated. There is not the slightest doubt about the existence of these mysterious markings on Mars, but what they are or what causes the changes in them is not known at present. One Jean believe whatever one likes, and 'there is no danger of being burned at the stake ,for one's beliefs, however wild. No telescope as yet constructed is powerful enough to^ reveal the Martian at work digging his irrigation canals, and no radio receiving station on earth has as yet picked up any Martian stations' broadcasts on the result of-the current year's snow melting. It should be added here that there are scientists who declare that there is no melting snow to fill imaginary canals —that the white caps at the poles of Mars are composed of frozen carbon dioxide, and that the so-called canals, if not optical illusions and nothing more, are merely cracks in a dried-up world which could not possibly support life as we know it. But such scientists are totally devoid of romance!-

, AN 'EXCITING MOON. If oncbhappe'ned to be living on-Mars one would^en joy the, unique experience of having two moons to brighten up the heavens when the sun' had set. These two moons were discovered in 1877. One, "which they named Phobos, has a diameter of a little over

ten miles, .but .what this moon lacks in* size, it makes .-,up;in speed. Twice in-every.-day Phobos rises in the west and sets in the east, so rapidly does itmove round its ..parent body, and .in doing this it reverses the direction utj

which the earth's one and only < moon moves. The other satellite of Mars is named Deimon. This, is slightly smaller than its companion Phobos, and in comparison is a laggard, taking two days to accomplish what Phobos does twice a day, and so apparently travelHnilTihthe "normal" - direction —east to f\Sses&-. . ■ ' ,^fp#SMartian viewing the earth would see^jt as a morning and evening star of siiperb brilliance, accompanied by quite .a; satellite—our moon. The earth-man observing Mars during the next few weeks will see abody which appears 63 times smaller than the moon. In other words, tit would require a telescope magnifying 63 times to make Mars look; as large as the' moon does to the naked eye. A telescope is, of course, '■ necessary to s^ee the.markings and-moons of Mars, but the naked-eye observer win be rewarded with quite a fine spectacle.