Iditarod pioneer., 1914-10-03
COMET NOW TO BE SEEN
 IN NORTHERN SKY

For some time past there has been visible in this latitude comet of considerable bril- liancy, which can be seen with the naked eye in the northern heavens. The celestial visitor appears to be progressing in north westerly direction, and its flight can be read fly noted by its relative position to neigh boring stars from night to night While not nearly so brilliant as the Haley comet seen few years ago, it can easily be distin- guished when there is no moon.
 The following article by Garrett P Ser viss, the eminent writer on astronomical subjects will be of interest at this time:
 "A large part of the fear that great comets have always inspired is due to an instinc- tive dread of their tremendous power for evil They look like besoms of destruction, and those who know nothing about astron- omy accept them at their apparent face value
 And, in truth, if they could come within hitting distance of the earth they would do an enormous amount of damage, and some of them might be capable of putting the aarth temporarily out of commission as an inhabited globe.
 'The terror that was aroused in many quarters by Halley's comet in 1910 is sure to recur on the appearance of any new comet, so that it is worth while to consider what an evilly disposed comet could do to the earth if it got chance.
 There are two ways in which comet could cause damage to the earth-hrst, by running straight into it with 15,000 times the velocity of an express train, and second, by injecting the atmosphere with the poison ous or stihng gases contained in its tail.
 "Let us consider the first case of comet shock
 Two things have to be taken into ac- count namely, the velocity and the weight of the colliding comet, considered as gigan- tic projectile shot against the earth as a target
 Comets are very deceptive in regard to weight or mass. They are enormously large, but relatively very light. The comet that appeared in 1861 first grazed the sun and then swept the earth with its tail.
 "Halley's comet also occupied vastly more space than the earth but 8 careful estimate has shown that it probably did not weigh more than 30,000,000 tons, which is much less than the weight of the material ex- cavated to make the Panama canal
 'It might be thought, then, that the earth is in no more danger from such comet than a battleship is iron 8 boys bean shooter. But now the velocity begins to come into play. The speed of comet at the earth's distance from the sun would be about twenty six miles per second
 "A mass of 3O,0OO,00O tons shooting through space at a velocity of twenty yslx miles per second would develop in round numbers about twenty qulntlllion foot pounds of energy, equivalent to the develop ment in one second of thirty six thousand million million horse power.
 ''Where the comet struck something rock, soil, vegetation-Wouid be melted, vitriied, and even vaporized in an instant, for all this tremendous energy would be turned into heat through the sudden and complete arrest of the swift motion ot the comet. The 600 quintillions of absolute units of energy developed by the stopping of the comet would furnish enough heat to liouefy more than a million million tons of solid iron
 'The result would be a very big and a very deep hole in the earth. Thousands of square miles would be more or less di- TeCtly dHeCtSu Dy tAC tCiiAhiS AAiPoS', AoA the shock would be greater than that of the mightiest earthquake, and perhaps buildings would tumble into ruin and noun tans would shake of their fringes of rock in all parts of the globe, while the sea would hurl itself in whelming tidal waves upon every coast and drown all the low lying islands.
 "The atmospheric disturbances would also be enormous. The sudden development of great heat at the point of collision would unbalance the air currents and destructive and capricious winds would blow to and fro over the earth.
 "We have only a little space left to con sider the effects of collision between the earth and the tail of comet This is some thing that has actually occurred two or three times within century. As already said the comet of 1861 enveloped the earth with the spreading end of its tail for a few hours, and in 1910 Halley's comet brushed its tail over the earth, but appar- ently the electric repulsion developed pre- vented the gases of the tail from entering the atmosphere It is possible that in every case this would occur, so that electricity may be an effective guardian against dele terious substances that might otherwise be introduced into the atmosphere from the switching tails of close passing comets.