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THE NEBUL?

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how wondrous a sight did james think the milky way! evening after evening would he stare at the weird-looking object. moonlight eclipsed it, as sunlight the stars. the atmosphere through which we contemplate the heavens at times obscures their glory. that dreamy radiance is easily concealed from view. the bold planet looks down upon us with an unblinking eye. the fixed stars peep more coyly, with an uncertain lustre. the milky way, yet more retiring, seldom deigns to do more than glance timidly at us here. with our magnificent climate in australia, we are favoured beyond most countries with its soft, peculiar light.

“what is a nebula, father? said james.

a white, cloudy patch in the heavens. there are about five thousands of them scattered about space.

you said the milky way was made up of stars and nebul?, and that many patches of white, when looked at with a good telescope, turn out to be only lots of stars.

yes. these are the resolvable nebul?. but there are irresolvable,—that is, some of them still look cloudy with our best telescopes. can you find me a nebula in orion?

what must i look for?

a small, distinct, white patch of light.

no; i don’t see it.

[pg 64]look again. do you see the belt, with a bright star over it, and one about the same distance below it?

i see all that clear enough, but not your nebula.

look, boy, steadily and closely between the belt, and that top bright star rigel, where on the atlas is pictured the sword-handle of the great hunter.

i don’t feel very sure, but i fancy i can distinguish something that ought to be it.

many folks, my boy, can see what they are told to expect. well, that white irregular patch of light has had telescopes looking at it a good while, without anything being seen beyond a dreamy-looking cloudy matter.

i’ll be bound lord rosse solved the riddle.

he did not for some time. he was able at last to think he could see stars; then by more patient watching he resolved the nebula into sandheaps of stars—millions upon millions.

what! millions upon millions where other telescopes could not distinguish one star. what shape is orion’s nebula?

it is rather patchy, with innumerable streamers of light, as if wind were blowing the gauze stuff about in all directions. you might fancy in it the jaws and head of a monster, with an elephant’s proboscis.

what a nice little nose that must be.

one part rises like a conical cloud in the midst of the black sky. in the part which had appeared mottled rosse found a blaze of stars.

[pg 65]can all the nebul? be observed by the naked eye?

no, my lad, very few.

but after all they are only lots of stars got crowded together like, because they are so far from us.

yet there are nebul? not to be resolved into stars even by rosse’s six feet mirror. just turn round to the southern cross. you see the two bright pointers to the cross, a part of the centaur. look now to the other side of the cross, where there is a collection of stars scattered about. that is the argo or ship.

ah! i can see a sort of light there. is that the argo nebula?

yes, and a very large one it is. thousands of stars can be observed in it by the telescope; but beyond these is still the same filmy light, as irresolvable as ever.

there must be a lot of nebul? by the cross, judging by the blaze of light.

there is a very fine one there, of a blue colour. one near spica, of the virgin, is quite round, and of enormous size. but there is a very odd crab nebula between orion and the bull’s eye. it branches out like the claws of a crab.

what an enormous crab!

we have a dumb-bell nebula near the lyre.

oh! who could swing that about? pray tell me some more about these queer creatures, father.

many in the south are planetary nebul?, as they are in the midst of a cluster of stars.[pg 66] they are always of a pale blue colour. some are double ones. about a dozen nebul? are annular, or ring-shaped. some are double or treble ringed. others have rings within rings, and star-like eyes in the darkness. a few have a long, parsnip form. there are solid nebul?, and hollow ones. one near castor was found by rosse to be arched like eyebrows above and below, with a curious, crab-like form in the middle.

i wonder what it would look like should a better telescope reach it!

wonder, indeed! some nebul? seen by herschel get quite another shape with rosse. the six-feet mirror gives another look to that by the three-feet one.

then i can scarcely believe the present shapes, as a better instrument may resolve the thing into another creature altogether. but is there any other sort beside the globular and annular?

yes; a good many are spiral, or corkscrew form.

something like a shaving that a plane fetches off a plank, father.

but some of your celestial shavings have a wild look. clever men have fancied that the star-dust is rolling up that way by a sort of gravitation into a regular form.

what of the two clouds in the heavens opposite to the southern cross, down in the south? they look uncommonly like monster nebul?.

and monsters indeed they are. in the larger one of them three hundred nebul? and[pg 67] globular clusters of stars have been distinguished, and fifty in the smaller one.

then there is room enough in the cloud for a whole universe?

yes, when we find the larger magellanic cloud, or nubecula major, as it is called, taking up many times the space occupied by the sun in the sky. the nubecula minor, or little cloud, is about one-fourth the size of the larger.

what do you mean by nubecula?

a little cloud. they are called the magellanic clouds because first noticed in the voyages of magellan the portuguese, three hundred years ago.

what a space they must take up in reality!

especially if, as astronomers believe, the clusters of stars and patches of nebulous matter in the two clouds there are as far off from each other as from this earth.

what is known about the coal-sacks?

the larger coal-sack, or black empty space not far from the two clouds, is of a pear shape, and occupies a space of eight degrees long by five broad. its darkness is only comparative, as two hundred stars have been noticed therein by a good telescope.

are the nebul? of the clouds peculiar?

one in the centre is very large, and has an odd dark space in its middle. it is also surrounded by a circle of ten other nebul?.

like bright guards around a king.

another consists of four starry centres, or nuclei, which are curiously united by a very faint nebulous matter.

[pg 68]do, father, tell me more of these nebul?.

then i will talk about some singular filaments, or threads of light, seen around the nebul?, which have much puzzled astronomers. those filaments about the nebul? of orion and argo are wonderfully strange.

they are the arms, i suppose, pointing into the dark space near, as much as to say,—‘you know nothing about us, or of what we can see around us, looking so black to you, and so bright to us.’

not a bad idea, boy. when sir john herschel had a look at our southern hemisphere, he observed beyond the nebul? a few scattered, faint bits of light in the dark region, too fine for him to turn into nebul? by his glass, and looking like some more distant light blushing through the darkness.

they are like telegraphic messages, father.

about forty of these strange glimmerings of future universes yet to be revealed were seen by sir john.

well, dear father, you can’t go further than that. if it take 60,000 years for some of the stars to send us their light, just to say ‘how do you do?’ how long would it take for these faint, modest blushes of the distant sky?

how great, then, is god, my son, and how grateful should we be for his notice! let us so please him here, that after death our souls may fly to that heaven of joy he has prepared, wherever in the vast universes of his it may be.”

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