Star-land: Being Talks With Young People About the Wonders of the Heavens

by Robert S. Ball

OTHER GREAT SHOWERS.

To illustrate what I have said, we will speak about another system of shooting stars; they are due every August, from the 9th to the 11th, and their directions diverge from a point in the constellation of Perseus. I may remind you of the dates of the recurrence of this shower as well as of the November meteors of which we have just spoken, by quoting the following production:—

If you November’s stars would see,
About the fourteenth watching be.
In August, too, stars shine through heaven,
On nights between nine and eleven.

It may be worth your while to remember these lines, and always to keep a look-out on the days named. The August meteors, the Perseids we often call them, do not make gorgeous displays, in particular years, with the regularity of the Leonids. There have been, no doubt, some exceptionally grand showers between the 9th and the 11th of August, but we cannot predict when the next splendid one is due. There are vast numbers of stragglers all round the track of the Perseids. In fact, it would seem as if the great race had gone on for such a long period that the cluster had to a great extent broken up, and that a large proportion of the meteors were now scattered the whole way around the course with tolerable uniformity. This being so, it follows that every time we cross the track we are nearly certain to fall in with a few of the stragglers, though we may never enjoy the tremendous spectacle of a plunge through a dense host of meteoroids.

There are many other showers besides the two I have mentioned. Some shooting stars are to be seen almost every fine night, and those astronomers who pay particular attention to this subject are able to make out scores of small showers which might not interest you. Each of these is fully defined by the night of the year on which it occurs and the position of the point in the heavens from which the meteors radiate. Of these I must mention one. It is not usually very attractive, but it has a particular interest, as I shall now explain.

On the 27th of November, 1872, a beautiful meteoric shower took place. You will notice that though the month is the same, the day is entirely different from that on which the Leonids appear. This shower of the 27th is called the Andromedes, because the lines of direction of the shooting stars of which it is composed seem to diverge from a point in the constellation Andromeda. Ordinarily speaking, there is no special display of meteors connected with the annual return of this day; but in 1872 astronomers were astonished by an exhibition of shooting stars belonging to this system. They were not at all bright when compared with the Leonid meteors. They were, however, sufficiently numerous to arrest the attention of very many, even among those who do not usually pay much attention to the heavens.

The chief interest of the shower of Andromedes centers in a remarkable discovery connecting meteors and comets. There is a comet which was discovered by the astronomer Biela. It is a small object, requiring a telescope to show it. This comet completes each revolution in a period of about seven years; or rather, I should say, that was the time which the comet used to spend on its journey, for a life of trouble and disaster seems of late to have nearly extinguished the unfortunate object. In 1872 the comet was due in our neighborhood, and on the night of the 27th of November, in the same year, the earth crossed the track, and, in doing so, the shower of shooting stars was seen. This was a remarkable coincidence. We crossed the path of the comet at the time when we knew the comet ought to be there; and though we did not then see the comet, we saw a shower of shooting stars, and a wonderful shower too. A circumstance so peculiar suggested at once that the comet and the shooting stars must in some way or other be connected together. This is a suggestion we can test in another manner. We know the history of the comet, and we are aware that at the very time of the shower, the comet was approaching from the direction of the constellation of Andromeda. It was coming, in fact, from the very quarter whence the shooting stars have themselves travelled. Taking all these things together, it seems impossible to doubt that the shoal of shooting stars was, if not actually the comet itself, something closely connected with that famous body.