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such inconceivable distances in the regions of space, with what line shall we measure the distance of those which are a thousand or a million of times as much farther from them, as these are from us.
If the annual parallax of a star were accurately known, it would be easy to compute its distance by the following rule: As the sine of the star's parallax:
Is to radius, or ninety degrees ::
So is the Earth's distance from the sun:
To the star's distance from the sun.
If we allow the annual parallax of the nearest star to be 1', the calculation will be,
As 0.0000048481368-Nat. Sine of 1".
Is to 1.0000000000000=Nat. Sine of 90°.
So is 95,273,868.867748554=Earth's distance from the sun. To 19,651,627,683,449 Star's distance from the sun.
In this calculation we have supposed the earth to be placed at the mean distance of 24,017 of its own semi-diameters, or 95,273,868.867748554 miles from the sun, which makes the star's distance a very little less than twenty billions of miles. Dr. Herschel says that Sirius cannot be nearer than 100,000 times the diameter of the earth's orbit, or 19.007,788,800,000 of miles.
Biot, who either takes the earth's distance greater than he lays it down in his Traité Elementaire d' Astronomie Physique, or has made an errour in figures, makes the distance 20,086,868,036,404. Dr. Brewster makes it 20, 159,665,000,000 miles. A mean of these computations, is 20 billions; that is, 20 millions of millions of miles, to a parallax of i"
Astronomers are generally agreed in the opinion that the annual parallax of the stars is less than 1", and consequently that the nearest of them is placed at a much greater distance from us, than these calculations make it. It was, however, announced during the last year, that M. D'Assas, a French astronomer, had satisfactorily established the annual parallax of Keid, (a small star 8 N. of Gamma Eridani,) to be 2', that of Rigel, in Orion to be 1". 43, and that of Sirius to be 1'. 24. If these results may be relied on, Keid is but 10 billions, Rigel but 14 billions, and Sirius 16 billions of miles from the earth. This latter distance is, however, so great that, if Sirius were to fall towards the earth at the rate of a million of miles a day, it would take it forty three thousand, three hundred years to reach the earth; or, if the Almighty were now to blot it out of the heavens, its brilliance would continue undiminished in our hemisphere for the space of three years.
The most brilliant stars, till recently, were supposed to be situated nearest the earth, but later observations prove that this opinion is not well founded, since some of the smaller stars appear to have, not only a greater annual parallax, but an absolute motion in space, much greater than those of the brightest class.
What conclusion may be drawn from this fact in regard to the distances of the fixed stars? If the annual parallax of a star were known, by what simple rule could you compute its distance? If we allow the annual parallax of the nearest star to be I", what will its distance be? What is a mean of the calculations of different astroomers, for a parallax of 1'? What recent observations indicate a greater parallax to some of the stars? If the parallax of Sirius be 1' .24, what will be its distance? How long would it require, passing through this distance, at the rate of a million of miles a day, to reach the earth, and how long would its light continue, undiminished to us, were it to be blotted from the heavens? What has been supposed to be the relative distance of the most brilliant stars from the earth? What do later observations prove, in regard to this opinion?
It has been computed that the light of Sirius, although twenty thousand million times less than that of our Sun, is, nevertheless, three hundred and twenty-four times greater than that of a star of the sixth magnitude. If we suppose the two stars to be really of the same size, it is easy to show that the star of the sixth magnitude is fifty-seven and one third times farther from us than Sirius is, because light diminishes as the square of the distance of the luminous body increases.
By the same reasoning it may be shown, that if Sirius were placed where the sun is, it would appear to us to be four times as large as the Sun, and give four times as much light and heat. It is by no means unreasonable to suppose, that many of the fixed stars exceed a million of miles in diameter.
We may pretty safely affirm, then, that stars of the sixth magnitude, are not less than 900 millions of millions of miles distant from us; or a million of times farther from us than the planet Saturn, which is scarcely visible to the naked eye. But the human mind, in its present state, can no more appreciate such distances than it can infinity; for if our earth, which moves at more than the inconceivable velocity of a million and a half of miles a day, were to be hurried from its orbit, and to take the same rapid flight over this immense tract, it would not traverse it in sixteen hundred thousand years; and every ray of light, although it moves at the rate of one hundred and ninety-three thousand miles in a single second of time, is more than one hundred and seventy years in coming from the star to us.
But what is even this, compared with that measureless extent which the discoveries of the telescope indicate? According to Dr. Herschel, the light of some of the nebulæ, just perceptible through his 40 feet telescope, must have been a million of ages in coming to the earth; and should any of them be now destroyed, they would continue to be perceptible for a million of ages to come.
Dr. Herschel informs us, that the glass which he used, would separate stars at 497 times the distance of Sirius.
It is one of the wonders of creation that any phenomena of bodies at such an immense distance from us should be perceptible by human sight; but it is a part of the Divine Maker's plan, that although they do not act physically upon us, yet they should so far be objects of our perception, as
Suppose the light of Sirius to be twenty thousand million times less than that of our sun, how would it compare with that of a star of the sixt magnitude? If we suppose the two stars to be of the same size, how much farther oft is the star of the sixth magnitude, than Sirius is? Suppose Sirius to be placed where our Sun is, how would its apparent magnitude, and its light and heat compare with those of the sun? What may we generally affirm of the distance of stars of the sixth magnitude? Can the human mind appreciate such distances? What illustrations can you give to show their immensity? What is this distance compared with that of the telescopic stars, and the nebula? Why are we able to see bodies at so great a distance?
to expand our ideas of the vastness of the universe, and of the stupendous extent and operations of his omnipotence.
"With these facts before us," says an eminent astronomer and divine, "it is most reasonable to conclude, that those expressions in the Mosaic history of Creation, which relates to the creation of the fixed stars, are not to be understood as referring to the time when they were brought into existence, as if they had been created about the same time with our earth; but as simply declaring the fact, that, at whatever period in duration they were created, they derived their existence from God."
"That the stars here mentioned," (Gen. i. 16.) says a distinguished commentator,* were the planets of our system, and not the fixed stars, seems a just inference from the fact, that after mentioning them, Moses immediately subjoins, 'And Elohim set them in the firmament of the heaven to give light upon the earth, and to rule over the day and over the night;' evidently alluding to Venus and Jupiter, which are alternately our morning and evening stars, and which 'give light upon the earth,' far surpassing in brilliancy any of the fixed stars."
However vast the universe now appears; however numerous the worlds which may exist within its boundless range, the language of Scripture, and Scripture alone, is sufficiently comprehensive and sublime, to express all the emotions which naturally arise in the mind, when contemplating its structure. This shows not only the harmony which subsists between the discoveries of the Revelation and the discoveries of Science, but also forms by itself, a strong presumptive evidence, that the records of the Bible are authentic and divine.
We have hitherto described the stars as being immoveable and at rest; but from a series of observations on double stars, Dr. Herschel found that a great many of them have changed their situations with regard to each other; that some perform revolutions about others, at known and regular periods, and that the motion of some is direct, while that of others is retrograde; and that many of them have dark spots upon their surface, and turn on their axes, like the sun.
A remarkable change appears to be gradually taking place in the relative distances of the stars from each other in the constellation Hercules. The stars in this region appear to be spreading farther and farther apart, while those in the opposite point of the heavens seem to close nearer and nearer together in the same manner as when walking through a
*S. Turner, F. S. A. R. A. S. L., 1832.
With these facts before us, what may we reasonably conclude with regard to the expressions in the Mosaic history which relate to the creation of the fixed stars? What is the opinion of Mr. Turner in regard to the stars here mentioned? To what is the expression, "To rule over the day and over the night," supposed to allude? Give some account of the real motions of the fixed stars. What remarkable changes are taking place in the constellation Hercules?
forest, the trees towards which we advance, appear to be constantly separating, while the distance between those which we leave behind, is gradually contracting.
From this appearance it is concluded, that the Sur., with all its retinue of planetary worlds, is moving through the regions of the universe, towards some distant centre, or around some wide circumference, at the rate of sixty or seventy thousand miles an hour; and that it is therefore highly prob able, if not absolutely certain, that we shall never occupy that portion of absolute space, through which we are at this moment passing, during all the succeeding ages of eternity.*
The author of the CHRISTIAN PHILOSOPHER endeavours to convey some idea of the boundless extent of the universe, by the following sublime illustration :—
"Suppose that one of the highest order of intelligences is endowed with a power of rapid motion superior to that of light, and with a corresponding degree of intellectual energy; that he has been flying without intermission, from one province of creation to another, for six thousand years, and will continue the same rapid course for a thousand millions years to come; it is highly probable, if not absolutely certain, that, at the end of this vast tour, he would have advanced no farther than the 'suburbs of creation,'—and that all the magnificent systems of material and intellectual beings he had surveyed, during his rapid flight, and for such a length of ages, bear no more proportion to the whole empire of Omnipotence, than the smallest grain of sand does to all the particles of matter contained in ten thousand worlds."
Were a seraph, in prosecuting the tour of creation in the manner now stated, ever to arrive at a limit beyond which no farther displays of the Divinity could be perceived, the thought would overwhelm his faculties with unutterable emotions; he would feel that he had now, in some measure, comprehended all the plans and operations of Omnipotence, and that no farther manifestation of the Divine glory remained to be explored. But we may rest assured that this can never happen in the case of any created intelligence.
There is moreover an argument derivable from the laws of the physical world, that seems to strengthen, I had almost said, to confirm, this idea of the Infinity of the material universe. It is this-If the number of stars be finite and occupy only a part of space, the outward stars would be continually attracted
* Professor Bessel does not fall in with this prevailing opinion.
What conclusion is drawn from this appearance? Shall we then probably ever Occupy that portion of space through which we are now passing, again? What illustration does the author of the Christian Philosopher give in order to convey some idea of the boundless extent of the universe? Were a seraph ever to arrive at a limit beyond which no farther displays of the divine glory could be perceived, how would the idea affect him? Is it probable that such a place exists in the universe, or within the scope of any created intelligence?
to those within, and in time would unite in one. But if the number be infinite, and they occupy an infinite space, all parts would be nearly in equilibrio, and consequently each fixed star, being equally attracted in every direction, would keep its place.
No wonder, then, that the Psalmist was so affected with the idea of the immensity of the universe, that he seems almost afraid lest he should be overlooked amidst the immensity of beings that must needs be under the superintendence of God; or that any finite mortal should exclaim, when contemplating the heavens-"What is man, that THOU art mindful of him!"
FALLING, OR SHOOTING STARS.
THE phenomenon of shooting stars, as it is called, is common to all parts of the earth; but is most frequently seen in tropical regions. The unerring aim, the startling velocity, and vivid brightness with which they seem to dart athwart the sky, and as suddenly expire, excite our admiration; and we often ask, "What can they be?"
But frequent as they are, this interesting phenomenon is not well understood. Some imagine that they are occasioned by electricity, and others, that they are nothing but luminous gas. Others again have supposed, that some of them are luminous bodies which accompany the earth in its revolution around the sun, and that their return to certain places might be calculated with as much certainty and exactness as that of any of the comets.
Dr. Burney, of Gosport, kept a record of all that he observed in the course of several years. The number which he noticed in 1819, was 121, and in 1820, he saw 131. Profes Green is confident that a uch larger number are annually seen in the United States.
Signior Baccaria supposed, they were occasioned by electricity, and thinks this opinion is confirmed by the following observations. About an hour after sunset, he and some friends, that were with him, observed a falling star, directing its course directly towards them, and apparently growing larger and larger, but just before it reached them it disap
Where does the phenomenon of falling, or shooting stars occur? What is there to excite our admiration in this phenomenon? Is this interesting phenomenon well understood? What are the different opinions in regard to them? How many shooting stars did Dr. Burney observe in the years 1819 and 1820? Is it probable that a much larger number is seen every year in the United States? What did Baccaria suppose they were occasioned by, and what observations did he make to strengthen his opinion?