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<v Speaker 1>Section twenty of Sun, Moon and Stars Astronomy for Beginners.

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<v Speaker 1>This is a LibriVox recording. All LibriVox recordings are in

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<v Speaker 1>the public domain. For more information or to volunteer, please

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<v Speaker 1>visit LibriVox dot org. Read by Larry Wilson, Sun Moon

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<v Speaker 1>and Stars Astronomy for Beginners by Agnes Gibernon. Comets and Meteors.

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<v Speaker 1>It is the glory of God to conceal a thing,

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<v Speaker 1>Proverbs twenty five two. An interesting discovery has been made.

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<v Speaker 1>It appears that some sort of mysterious tie exists between

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<v Speaker 1>comets and meteors. For a long while, this was never suspected.

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<v Speaker 1>How should it be the comets so vast in size,

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<v Speaker 1>the meteor so small and evanescent. How could it possibly

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<v Speaker 1>be supposed that the one had anything to do with

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<v Speaker 1>the other. But supposings often have to give in to facts.

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<v Speaker 1>Astronomers have gradually become convinced that there certainly is a

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<v Speaker 1>connection between the two. Comets and meteor streams are found

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<v Speaker 1>to occupy, sometimes at least, the very same pathways in

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<v Speaker 1>the heavens, the very same orbits around the Sun. A

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<v Speaker 1>certain number of meteor systems are now pretty well known

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<v Speaker 1>to astronomers as regularly met by our Earth at certain

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<v Speaker 1>points in her yearly journey. Some of these systems or

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<v Speaker 1>rings have each a comet belonging to it, not merely

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<v Speaker 1>journey near, but actually in the midst on the same orbit.

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<v Speaker 1>Perhaps it would be more correct to say that the

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<v Speaker 1>meteors belong to the comet than that the comet belongs

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<v Speaker 1>to the meteors. We tread here on uncertain ground. For

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<v Speaker 1>whether the meteors spring from the comet, or whether the

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<v Speaker 1>comet springs from the meteors, or whether both spring from

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<v Speaker 1>the same source, cannot yet be quite definitely asserted, though

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<v Speaker 1>we cannot fully explain the kind of connection. Yet a

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<v Speaker 1>connection there plainly is. So many instances are now known

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<v Speaker 1>of a common and a media ring traveling together, that

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<v Speaker 1>it is doubtful whether any such ring could be found

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<v Speaker 1>without a comet in its midst. By and by, the

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<v Speaker 1>doubt may spring up whether there ever exists a comet

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<v Speaker 1>without a train of meteors following them. Among the many

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<v Speaker 1>different media rings which are known, two of the most

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<v Speaker 1>important are the so called August and November systems. Of

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<v Speaker 1>these two, the November system must claim our chief attention,

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<v Speaker 1>not that we are at all sure of these being

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<v Speaker 1>the most important media rings in the Solar system. On

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<v Speaker 1>the contrary, as regards the November ring, we have some

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<v Speaker 1>reason to think that matters may lie just the other way.

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<v Speaker 1>The comet belonging to the November system is a small one,

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<v Speaker 1>quite an insignificant little comet, only visible through a telescope.

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<v Speaker 1>We do not, of course ow positively that larger comets

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<v Speaker 1>in greater media systems generally go together, but to say

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<v Speaker 1>the least, it seems likely. And if the greatness of

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<v Speaker 1>a ring can at all be judged by the size

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<v Speaker 1>of its comet, then the November system must be a

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<v Speaker 1>third rate specimen of its kind. It is of particular

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<v Speaker 1>importance to us merely because it happens to be the

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<v Speaker 1>one into which our Earth plunges most deeply, and which

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<v Speaker 1>we therefore see and know the best. The August ring is,

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<v Speaker 1>on the contrary, connected with a magnificent comet, and may

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<v Speaker 1>be a far grander system. But our pathway does not

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<v Speaker 1>lead us into the midst of the August meteors, as

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<v Speaker 1>into those of November. We pass seemingly through its outskirts.

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<v Speaker 1>The meteors of the November system are very small. They

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<v Speaker 1>are believed to weigh commonly only a few grains each.

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<v Speaker 1>If they were larger and heavier, some of them might

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<v Speaker 1>find their way to Earth's surface only half diminished in

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<v Speaker 1>their rush through the air, but this they seem never

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<v Speaker 1>to do. Doubtless, meteor systems exist in the Solar System,

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<v Speaker 1>which our Earth does not encounter, containing much larger and

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<v Speaker 1>heavier meteors. It is well for us that we do

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<v Speaker 1>not plunge into any such ring, or we might find

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<v Speaker 1>our atmosphere an insufficient protection. The last grand display of

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<v Speaker 1>the November system of meteorites took place in the years

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<v Speaker 1>eighteen sixty six to eighteen sixty nine, being continued more

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<v Speaker 1>or less during three or four November's following. The next

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<v Speaker 1>grand display is not expected until the year eighteen ninety nine.

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<v Speaker 1>For this system, Leonides, as it is called footnote because

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<v Speaker 1>the falling stars in this display seem all to shoot

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<v Speaker 1>towards us from a spot in the constellation Leo in

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<v Speaker 1>Footnote seems to have a time or year of thirty

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<v Speaker 1>three and a quarter earthly years. The shape of its

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<v Speaker 1>orbit is a very long ellipse, near one end of

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<v Speaker 1>which is the Sun, while the other end is believed

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<v Speaker 1>to reach farther away than the orbit of Uranus. A

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<v Speaker 1>great deal of curiosity has been felt about the actual

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<v Speaker 1>length and breadth and depth of the stream of meteorites

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<v Speaker 1>through which our solid Earth has so often plowed her way.

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<v Speaker 1>During many hours at a time, lookers on have watched

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<v Speaker 1>the magnificent display of heavenly fireworks. Not a mere shooting

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<v Speaker 1>star here and there, as uncommon nights, but radiant meteors

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<v Speaker 1>flashing and dying by thousands through the sky. In eighteen

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<v Speaker 1>sixty six, no less than eight thousand meteors and two

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<v Speaker 1>hours and a quarter were counted from the Greenwich Observatory.

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<v Speaker 1>A natural wonder sprang up in many minds as to

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<v Speaker 1>the extent of the ring from which they fell. For

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<v Speaker 1>not in one night only, but in several nights during

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<v Speaker 1>three or four years, and that not once only, but

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<v Speaker 1>once in every thirty three years, thousands and tens of

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<v Speaker 1>thousands appeared to have been stolen by our Earth from

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<v Speaker 1>the media ring, never again to be restored. Yet each

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<v Speaker 1>time we touched the ring, we find the abundance of

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<v Speaker 1>little meteors in no way seemingly lessened. When speaking of

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<v Speaker 1>a ring of meteors, it must not be supposed that

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<v Speaker 1>necessarily the meteors form a whole broken ring all around

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<v Speaker 1>the long oval orbit. There may be no breaks, there

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<v Speaker 1>may be more or less thin scattering throughout the entire

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<v Speaker 1>length of the pathway. But the meteor certainly seemed to

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<v Speaker 1>cluster far more densely in some parts of the orbit

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<v Speaker 1>than in other parts. And it was about the size

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<v Speaker 1>of the densest cluster that so much curiosity was felt.

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<v Speaker 1>Little can be positively known, though it is very certain

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<v Speaker 1>that the cluster must be enormous in extent. Three or

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<v Speaker 1>four years running, as our Earth, after journeying the whole

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<v Speaker 1>way round the Sun came again to that point in

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<v Speaker 1>her orbit where she passes through the orbit of the Leonides.

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<v Speaker 1>She found the thick stream of meteors still pouring on,

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<v Speaker 1>though each year lessening in amount. Taking into account this

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<v Speaker 1>fact and also the numbers that were seen to fall

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<v Speaker 1>night after night, and also the speed of our Earth,

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<v Speaker 1>a rough estimate was formed. The length of this dense

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<v Speaker 1>cluster is supposed to reach to many hundreds of millions

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<v Speaker 1>of miles. The thickness or depth of the st miscalculated

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<v Speaker 1>to be in parts over hundreds of thousands of miles,

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<v Speaker 1>and the breadth perhaps not less than one hundred thousand miles.

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<v Speaker 1>Each meteor is probably at a considerable distance from his neighbors,

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<v Speaker 1>but the whole mass of them, when in the near

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<v Speaker 1>neighborhood of the Sun, must form a magnificent sight. And

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<v Speaker 1>if this be only a third rate system, what must

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<v Speaker 1>a first rate system be like? And how many such

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<v Speaker 1>systems are there throughout the Sun's wide domains. The most

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<v Speaker 1>powerful telescope gives us no hint of the existence of

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<v Speaker 1>these rings till we find ourselves in their midst It

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<v Speaker 1>may be that they are numbered by thousands, even by millions.

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<v Speaker 1>The whole of the Solar system, Nay, the very depths

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<v Speaker 1>of space beyond may, for aught, we know, be crowded

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<v Speaker 1>with meteor systems. Every comet may have his stream of

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<v Speaker 1>meteors following him, But though the comet is visible to us,

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<v Speaker 1>the meteors are not. Billions upon billions of them may

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<v Speaker 1>be ever rushing round our Sun, entirely beyond our camp

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<v Speaker 1>till one or another straggler touches our atmosphere to flash

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<v Speaker 1>and die as a shooting star. In our sight we have,

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<v Speaker 1>and with our present powers we can have no certainty

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<v Speaker 1>as to all this. But I may quote here the

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<v Speaker 1>illustration of a well known astronomical writer on the subject.

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<v Speaker 1>Suppose a blind man were walking out of doors along

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<v Speaker 1>a high road, and during the course of a few miles,

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<v Speaker 1>were to feel rain falling constantly upon him. Would it

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<v Speaker 1>be reasonable on his part if he concluded that a

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<v Speaker 1>small shower of rain had accompanied him along the road

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<v Speaker 1>as he moved, but that fine weather certainly existed on

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<v Speaker 1>either side of the road. On the contrary, he might

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<v Speaker 1>be sure that the drops which he felt were but

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<v Speaker 1>a few among millions falling altogether. Or look at the

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<v Speaker 1>rain drops on your window some dull ready day. Count

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<v Speaker 1>how many there are? Could you, with any show of

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<v Speaker 1>common sense, decide that those rain drops, and those alone,

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<v Speaker 1>had fallen that day in your town. So when we

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<v Speaker 1>find these showers of meteors falling to earth, we may

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<v Speaker 1>safely conclude that for every one which touches our atmosphere,

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<v Speaker 1>myriads rush elsewhere in space, never coming near us. End

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<v Speaker 1>of section twenty