Notes

New Zealand Tablet, 10 February 1910, Page 222

Notes

The Come.t It is always the smaller fry of scientists who are dead sure of things— greater a man’s knowledge the less he is inclined to dogmatise. This fact is illustrated by the very varying utterances that are being published regarding the size, progress, and potentialities of Halley’s Comet. It is at present about 140 million miles away, but will come within sixteen million miles before it disappears for another seventy years. As tails of comets sometimes extend from 20 to 35 million miles, it is probable, or at least very possible, that the tail of Halley’s comet may come into contact with our planet. In that case what would happen ? * • The Rev. Mr. Pairclough, who contributes 1 Astronimical Notes’ to one of the Christchurch papers, disposes of the question in very summary fashion. In this week’s * Notes he says: —‘Probably, if Halley’s Comet could

be condensed into solid. blocks, one of out ocean steamers cpuld take it for ballast. •• If the whole comet plunged into the earth, there would probably be a glow in the sky, perhaps a shower of shooting stars, and all would be over.’ E. C. Andrews, in an article on ‘ The Danger of the Comet ’ in the December number of Pearson’s Magazine, takes a much more serious view of the situation, and holds a very different opinions regarding the size of our visitor. ‘Suppose a heavy comet,’ he says, ‘ were to graze the earth, or in other words, pass across the sky within a few thousand miles of us. The head of Halley’s Comet is about 350,000 miles in diameter, its speed 1,000,000 miles an hour. . . The journey across the heavens would take about ten minutes, and during that ten minutes the surface of the earth immediately beneath it (supposing it to be a heavy comet) would be swept by fire, the ocean would rise to meet the clouds. . . As the comet receded, an immense tidal wave would follow in its wake and bury the burning land in water.’ While M. Flammarion, the well known French astronomer, writing in the New York Herald (Paris), is modest enough to say ‘ That he cannot foretell the result of such a situation. If the oxygen in the atmosphere were to combine with the hydrogen in the comet’s tail the inhabitants of the earth would die of suffocation. If, on the contrary, there was a diminution of nitrogen, an unexpected sensation of physical activity would be experienced by every one, and the human race would perish in a paroxysm of joy and delirium, probably delighted at its fate. As yet,’ continues M. Flammarion, ‘it is impossible to ascertain the dominant elements of the comet’s tail. Although the tails of comets are immense, they are so light and rarefied that our terrestrial atmosphere is like lead in comparison. They would be likened to a fog traversed by an engine at full speed.’ In the meantime it is comforting to be told that the earth has in all likelihood gone through the tails' of comets before without being any the worse.