OUR SOLAR SYSTEM

Hawera Star, Volume XLVI, 25 June 1927, Page 11

OUR SOLAR SYSTEM

COMETS AND EARTH

WHAT DOES IT HARBOUR

T\IIE world is coming to ail end! So said most ancients and many moderns whenever one of those wondrous, erratic, long-haired” celestial bodies came hurtling through space from inconceivable distances to appear before their startled vision. They were supposed to portend wars or some great disaster or the untimely passing of some great person, writes Captain Edwin T. Pollock, superintendent of the United States Naval Observatory in the “San Francisco Chronicle.” When beggars die there are no comets seen. The heavens themselves . blaze forth the death of PrincesWhat causes them? No one knows. Whence do they come, and whither do they go? The same answer can be given for most of them, for most seem to come from space in one direction. sweep around our sun, and disappear into another direction. Some, since they were first discovered, seem to belong to our own solar system. Some, when they were on their random way through our system, were evidently attracted by one of our planets, principally the largest one—Jupiter —so that paths were changed until they could not get away from the attractive influence of the planets and the sun. Then they lost their independence and joined our planets in sailing around our sun. and reappeared at. fairly regular intervals. “Fairly regular” is because every time one of those comets goes too near a large planet the latter causes a slight change in its path. Due to this change it sometimes happens that when a comet is expected to reappear, it turns up missing. What happened to it? Did it career off into space again to some other stellar system? Did it crash into some more substantial body such as a planet and become a part of it? Did it disintegrate into nothingness, or into a swarm of meteorities so small and so far apart as to be invisible-except when some of those particles entered our atmosphere, became luminous through fiction, and burned away as “falling stars”? Or, if of sufficiently large size, did they reach the earth only partially consumed, when, if found, they were gathered into museums? • Of course, the volume of the earth would be increased thereby, but it has been estimated that it would take about a billion years to accumulate an additional inch to the earth’s surface. If a bunch of meteorites had hit the earth at the same time what would have happened, especially if they were large? Sometimes a particularly large one has been seen and heard to burst like a gigantic fireworks bomb, showng a large number of stars lasting several minutes. The largest one yet found weighed 36

tons, and was brought back from Greenland by Peary. Recently scientists found in Arizona evidences of one that was estimated to have been 5000 feet in diameter. It made a crater over 4000 feet in diameter and 600 feet deep, while fragments of it were scattered in a concentric distribution for nearly five miles. Fortunately that part of the world was probably uninhabited when it struck, for they say it probably happened before the deluge, and that it may have been one of a flock of meteorites which formed the nucleus of a large comet. Many can remember the great comet of 1882 which was visible for months in the southern skv. Its brlliant head and scimitar-like tail 1,000,000 miles in length, stretched across the heavens almost from the horizon in the southeast to the horizon in the south-west. Was it such a comet that David saw when he “lifted up his eyes, and saw the angel of the Lord stand between the earth and the heaven, having a drawn sword in his hand stretched out over Jerusalem,” and he and the elders fell upon their faces? What if the comet’s path had crossed that of the earth? Some sav there would have been disaster and some say not — that the rarefied gases would have been dissipated in the earth’s atmosphere, and that there would have been a most brilliant star shower lasting for weeks, but that is a very optimistic view. Astronomical history fails to record any fairly near contacts with even a small comet, but in June of this year, one with the added weight of a hyphenated name comes relatively near, and we miss a collision by only two days. Its orbit is continually changing, due to Jupiter playing tag with it eery five or six yeai’S. and Jupiter may cause it to play tag -with us and finally catch us. The name Pons-Win-neclce is due to the comet having been discovered by the Frenchman. Pons, in 1819. and its orbit calculated. It was not observed again until 1858, when it was rediscovered by a German, Winnecke, and since it has been seen many timesAt its last appearance six years ago, its oybit passed inside that of the earth in its swing around the sun, but this year it goes beyond ours and its orbit crosses that of the earth four times, so that in June we miss a collision by two days and a few million miles. On June 26 it will be at its nearest to us, a paltry 4,000,000 miles away, and two days later it crosses our orbit. Two days more and we shall reach that crossing', so we can believe ourselves safe from any danger except a brilliant star shower from the tiny meteorites that will be tagging along behind to greet us.