Page:Popular Science Monthly Volume 16.djvu/271

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EXPECTED METEORIC DISPLAY.
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son examined the heavens in the region indicated, and there, in the early morning hours of December 2, 1872, detected two cloud-like objects. These he saw again on the morning of December 3d—by which time their position on the star-vault had changed, so that it was clear they were not nebulae or star-clouds, but veritable attendants on the sun, though whether comets or meteor-flights was not clearly made out. It was, however, clearly shown that neither of these objects could possibly have been the meteor-flight crossed by the earth on the night of November 27, 1872. It was equally certain that neither the meteor-flight nor these two cometic objects could have been Biela's comet itself—though all three were traveling in such courses that they might be called attendants of that body.

There for the time the history of Biela's comet has closed, Nothing more has been seen of it, either as a comet or as a meteor-flight, though scattered meteors traveling in its train were seen toward the end of November, 1877, and more would probably have been seen at the same part of last year if the skies then had not been overclouded in nearly all European countries.

The next passage of the earth athwart the track of the comet is the first, since that of November 27, 1872, during which a meteor shower could be expected to occur. The comet crossed the earth's track, or passed very near to it, early in April last; and though the interval is considerably longer between then and the end of November than elapsed between the comet's passage in 1872 and the display of that year, yet it is most probable that many meteoric attendants of the comet will be seen on some nights (or perhaps on several nights) between November 25th and December 1st, and quite possible that a very fine shower may be seen. The meteors will be well worth looking for in any case, since, if they are carefully observed and counted hour by hour, astronomers will probably obtain some further insight into the nature of the processes which lead to the dissipation of a comet and cause its path to be occupied over a range of many millions of miles by scattered meteoric attendants. To others than astronomers, the meteors will be full of interest; and it is not at all unlikely that they will appear in such numbers as to produce an exceedingly beautiful display.—Belgravia.

    erfues telegraphed to Pogson, "on November 27, 1872." But this is quite impossible. Any perturbation active enough to delay the comet's perihelion passage ten or twelve weeks would have entirely changed the character of the comet's orbit. But the very circumstance that the earth crossed the train of cometic attendants on November 27, 1872, showed that they were in the track of the comet, whose path could not, therefore, have been greatly altered. The case may be simply put thus: Either the comet's motions had been or had not been very greatly disturbed between 1852 and 1872: now, if they had been, the comet's path would no longer have passed near the earth's, and the comet could not have encountered the earth either on November 27, 1872, or at any other time; and if they had not been, the comet must have crossed the earth's track early in September, 1872, and therefore, in this case also, must have been far away from the earth on November 27, 1872.