Now let us look at the Earth being circled round the sun by the electro-magnetic Aether currents as it goes on to perform the other half of the orbit. In this case we have the orbital motion of the sun and the centrifugal force working conjointly, with the result that together they overcome the centripetal force, and the Earth is repelled and carried beyond its mean distance. Let _S_ represent the sun, the Earth being at point _C_ of its...o...b..t, after pa.s.sing round its perihelion, and at this decreased distance it is carried along by the circulating and denser Aether with its maximum velocity (Fig. 26).
Now while the Earth is going on to describe the half-circle _C_ _G_ _E_, the sun is still pursuing its journey at the rate of about 18,000 miles per hour, only this time in a direction away from the Earth. As, however, the Earth has not yet regained its mean distance of 92,000,000 miles, the centrifugal force is still greater than the centripetal force, so that the centrifugal force is urging the planet away from the sun with greater intensity than the centripetal force is attracting it, as the two forces are only in equilibrium at the mean distance of the Earth.
Thus, as stated, the orbital motion of the sun and the centrifugal forces are now working conjointly together, with the result that the Earth is repelled gradually further and further from its central body, until it reaches its maximum distance of 94,500,000 miles. While, however, the distance is gradually being increased, it is pa.s.sing into a part of the Aether possessing not only a decreased ma.s.s, but also a decreased velocity, with the result that the motive power or kinetic energy of the aetherial currents at the increased distance is gradually lessened, and as a natural result the velocity of the Earth is also decreased; so that by the time the Earth has got to its furthest distance from the sun, its...o...b..tal velocity is slowest, because of the decreased momentum of the aetherial currents.
Thus we can account for the difference of velocity of a planet in its...o...b..t by the same electro-magnetic Aether currents working in conjunction with the sun"s...o...b..tal motion, and that upon a strictly physical basis. This result is in perfect harmony with Kepler"s Second Law, which states that equal areas are described by the radius vector in equal times. Newton proved that by the Law of Gravitation Attraction he could account for this second law, as well as all the others, and as we have not destroyed that law, but perfected it by giving it its exact complement and counterpart, the same mathematical reasoning that applies to the centripetal force must equally apply to the centrifugal force, and if it is true that the centripetal force works harmoniously with the second of Kepler"s Laws, then it is equally true that the centrifugal force does also, as the two are inseparably and indisputably united together in the atomic Aether. We have, however, a physical basis for this centrifugal force, and we have an equal physical basis for the centripetal force, as we shall see later, and therefore, by the conjoint working of these two forces taken in conjunction with the orbital motion of the sun, we have now a physical conception for the first time of Kepler"s Laws, as well as a mathematical conception, that physical conception being derived from the pressure and motions of the universal Aether.
ART. 104. _Aether and Kepler"s Third Law._--In Art. 28 we saw that according to the Third Law of Kepler, the square of the periodic time was proportionate to the cube of the mean distance of that planet from its controlling centre. Newton proved that this Third Law was mathematically correct, and that it could be mathematically accounted for by the existence and operation of the universal Law of Gravitation.
As the centrifugal force is the exact opposite of that force in intensity, proportion and mode of operation, it follows that mathematically the centrifugal force also bears the same relation to the Third Law that the centripetal force does.
We have, however, a physical basis for the centrifugal force, and it is with the physical conception of this Third Law rather than with its mathematical character that we are now dealing. Kepler by his Third Law showed that the chief regulating factor in the orbital velocity of a planet was its mean distance from the sun.
The great regulator of the velocity of any planet in its...o...b..t is simply planetary distance, and planetary distance alone. If there were no other law which operated in the solar system than the centripetal force, or the attractive force due to gravity, then such factors as ma.s.s and density of a planet ought to play a most important part in the orbital velocity of a planet, as the centripetal force directly recognizes the influence of ma.s.s, that is, volume and density, but says nothing about mean distances. This fact unmistakably points to the existence, and demands the operation, of another force, which shall explain, and that on a physical as well as a mathematical basis, how it is that the mean distance of a planet from any centre regulates the orbital velocity of that planet.
The only real and true conception of such a force is to be found in the radiating waves and circulating motions of the aetherial medium, which waves, like water waves, increase in their radial outflow and extent with a regular decreasing intensity, and at the same time decrease in their angular velocity as they recede from the sun. With such a regular decrease of kinetic energy, there must necessarily be imparted to the planets, as their mean distance is increased, a decreased velocity of motion, with the natural result, that the further a planet is from the sun, the less will be its...o...b..tal velocity, and that in a regular and uniform proportion as the distance is increased.
Now let us view the matter for a moment in its application to the solar system, and by so doing show the simplicity of the explanation, and at the same time give added proof to the existence and operation of the circulating aetherial currents that exist in s.p.a.ce. Let us again picture the solar fires burning in all their fierceness and intensity, every atom and particle of the sun being thrown thereby into the most intense state of activity, and by their energy of motion creating electro-magnetic Aether waves in their myriads, which speed away from the sun on every side.
Under their influence, all subordinate worlds would be carried away into s.p.a.ce, were it not for the complementary Law of Gravitation Attraction, that is, the centripetal force. But to every planet, by the operation of some governing and determining principle, a mean distance has been given, and at that mean distance the two forces find their equilibrium; and by their conjoint and co-equal working hold each planet at that mean distance with a power that cannot be broken. Each power or force may be modified under certain conditions, as shown in the two preceding articles; but, whether the planet be repelled further away, or attracted nearer to the sun, through the onward motion of the sun, the two forces ever seek to maintain their equilibrium, and to place the planet at its mean position a.s.signed to it in the solar system.
The nearer that mean position is to the sun, the greater is the velocity of the aetherial currents which circulate round the sun; and the greater their ma.s.s, volume for volume, on account of the increasing density of the Aether, the nearer it is to the sun. The effect of this increased velocity, and the increased ma.s.s of the circulating Aether currents, is to impart to planets nearest to the sun the greatest orbital velocity; while, the greater the distance, the less will be the orbital velocity of the planet. That this is exactly in accordance with observation and experience may be proved by considering the respective mean distances and orbital velocities of the various planets.
Mercury, with a mean distance of 35,900,000 miles, is circled round the sun at the enormous rate of about 108,000 miles per hour, accomplishing its entire journey in the short period of 88 days. Venus, whose mean distance is about 67,000,000 miles, is carried round the sun at the reduced rate of 78,000 miles per hour, completing her orbit in the increased time of 224 days. Our own Earth, at the still further increased mean distance of 92,000,000 miles, performs her journey at the reduced velocity of 64,000 miles per hour, accomplishing the journey round the sun in a period of 365 days.
Thus, the further we get from the sun, the slower becomes the movement of a planet in its...o...b..t, and the longer it takes to complete its revolution round its controlling centre. Mars, at the increased distance of 141,000,000 miles, possesses a reduced velocity of 54,000 miles per hour, and completes its...o...b..t in the increased duration of 686 days. So the decrease of velocity goes on, as the planets increase their mean distance from the sun, as the following figures show--
MEAN DISTANCE. PERIOD OF ORBITAL VELOCITY REVOLUTION. PER HOUR.
Jupiter 482 millions 4,332 days 28,000 miles Saturn 884 " 10,759 " 21,600 "
Ura.n.u.s 1,780 " 30,687 " 1,800 "
Neptune 2,780 " 60.127 " 900 "
The relation of this decrease of velocity to the mean distance is exactly determined by Kepler"s Third Law, in which he states that the square of the periodic time is proportionate to the cube of the mean distance. That this is true has already been proved in Art. 28.
In conclusion on this point, let me ask the reader to try to conceive any other physical explanation for this decrease of orbital velocity as the mean distance is increased, than the one given here, namely, the decrease in the velocity and ma.s.s of the radiating and circulating Aether currents, and if such attempt is made, I premise that its only result will be utter failure. No other physical conception to account on a physical basis for all Kepler"s Laws can be given or conceived, than that which finds its origin in the universal electro-magnetic Aether, which by its pressures, tensions and motions gives rise to all the phenomena incidental to, and a.s.sociated with, planetary and stellar phenomena.
Therefore, inasmuch as all the laws of motion, and all Kepler"s Laws can be accounted for by a gravitating and rotatory Aether medium, those facts alone, apart from the explanation of other phenomena a.s.sociated with light and heat, would stamp the circulating Aether medium as the physical cause of all the motions and phenomena a.s.sociated with the whole of the celestial mechanism.
ART. 105. _Orbital Motions of Satellites and Planets._--According to Kepler"s First Law, the Earth and all the other planets move round the sun in orbits which are in the shape of an ellipse. Not only, however, is the first law true of planetary motion, it is equally true of the motions of all satellites moving round their primary planets. I wish, however, to point out, and prove in an indisputable manner, that Kepler"s First Law does not sufficiently explain and determine the exact orbit of any satellite as it revolves around its primary planet, or even of any planet as it revolves around the sun.
Simply because, if any satellite or planet is to perform a perfect ellipse as it revolves around its central body, that central body must only move for a time and must then come to rest, or partly return in its journey in order for a perfect ellipse to be formed, as shown in a previous figure. Now we know from observation that such a thing as rest in s.p.a.ce by any planet, or by the sun, is absolutely unknown in the celestial mechanism.
From Art. 92 we learned that the electro-magnetic Aether currents not only circulate round the sun, but they also circulate round each planet.
Thus we found there were electro-magnetic Aether currents circulating round each planet, while those planets themselves were circled round the sun by the Aether currents generated by the sun; the planetary Aether currents in their turn propel the satellites round their primary planets. It can easily be seen, therefore, that such phenomena as rest and return of a planet in its journey are physical impossibilities, for either the circulating Aether currents would have to cease circulating, or would have to return upon themselves in some inconceivable manner.
Thus there is ever going on this conjoint motion, so to speak, of the sun"s aetherial currents which circle all the planets round that body, and the planetary aetherial currents which circle all the satellites round their central body, and it is the effect of the conjoint working of these currents on the planets and satellites to which I wish to call the reader"s attention.
Let us in starting represent the earth"s...o...b..t by a perfect ellipse _A_ _B_ _C_ _D_, with the sun occupying one of the foci _S_ (Fig. 27). We will suppose that the earth is at point _A_ of its...o...b..t and is being circled round the sun with uniform velocity. As it is circled round the sun by the sun"s aetherial currents, at the same time its satellite the moon is being circled round the earth by the electro-magnetic Aether currents which circulate round that planet. We will represent the orbit of the moon by part of a smaller circle _D_ _E_ _F_, and suppose the moon to be at point _D_ of that orbit. The mean distance of the moon from the earth is about 240,000 miles, so that the diameter of the orbit is 480,000 miles, therefore the circ.u.mference of the orbit is 480,000 3.1416, which gives us about 1,500,000 miles.
[Ill.u.s.tration: Fig: 27.]
That distance is traversed in about 28 days, so that the moon"s average velocity in its...o...b..t, as it is circled or pushed round the earth, is about 2200 miles per hour. While, therefore, the moon is travelling 2200 miles, the earth in its journey round the sun has travelled about 64,800 miles in the same time. So that by the time the moon has travelled half its...o...b..t, that is, from _D_ to _F_, which would take about 14 days, the earth has also travelled in its...o...b..t 64,800 24 14 = 21,772,800 miles, with the result, that instead of the moon arriving at point _F_, which it would do if the earth were stationary, it really arrives at a point about 21,772,800 miles in front of that point.
In a similar way, while the moon goes on to describe the other half of the orbit, the earth still proceeds on its journey, so that at the end of 14 days it is again 21,772,800 miles further on, with the result, that the centripetal force (by which the moon is attracted to the earth) keeps it at the distance of 240,000 miles according to Kepler"s Second Law as explained in Art. 103.
The moon, therefore, completes its...o...b..t about 21,772,800 miles further on than it would do if the earth were stationary. The effect of this continual progress of the earth on the moon"s...o...b..t as it describes its...o...b..t round the sun is seen in the diagram. As the moon revolves round the earth thirteen times in one year, it performs thirteen revolutions round that planet; but it cannot be said that these orbits are perfect ellipses, as the earth is ever being circled round its central body, the sun. Even this diagram does not accurately represent the orbital motion of the moon through s.p.a.ce, as it a.s.sumes that the earth returns to the same point in s.p.a.ce from whence it started. This, however, is incorrect, as we have to remember that the sun has also an orbital velocity of 18,000 miles per hour, so that while the earth has performed one revolution in its...o...b..t, the sun has actually progressed through s.p.a.ce to the extent of 18,000 24 365 = 157,680,000 miles.
When we come to deal with the sun"s motion through s.p.a.ce, we shall see that this distance only represents a fraction of the sun"s...o...b..t, as it can be philosophically proved, that if the sun moves at all, it, too, obeys Kepler"s Laws; and therefore, according to his First Law, it also describes and possesses an orbit of its own. So that by the time the earth has made its annual revolution round the sun, the whole system has been carried 157,680,000 miles through s.p.a.ce, and therefore the earth does not complete a perfect ellipse, but its...o...b..tal motion round the sun will be represented by a similar kind of diagram to the one which represents the orbital motions of the moon, or any other satellite round its central body.
ART. 106. _Eccentricity of Orbit of Moon._--From astronomical observation we learn, that all the satellites and planets do not possess uniformity of motion, as they are carried round their controlling centres by the circulating aetherial currents, because the respective controlling centres themselves move through s.p.a.ce. The result is, that the orbit of any satellite or planet is not always of the same size, but constantly varies, sometimes having a larger circ.u.mference than at other times, and sometimes a smaller circ.u.mference.
This change in the size of the orbit of a satellite or planet is known as the eccentricity of the orbit, which eccentricity is constantly changing, being sometimes greater and sometimes less. We will look at this truth in its relation to the moon first, and then consider the same principle in its relation to the earth and other planets later on. For the purpose of ill.u.s.tration, we will consider the earth as being circled round the sun by the electro-magnetic Aether currents in a closed orbit, _A_ _B_ _C_ _D_, which forms a perfect ellipse, the sun occupying one of the foci _S_ (Fig. 28), the earth occupying a position in the orbit represented by point _C_, with the moon being circled round the earth by that planet"s aetherial currents. As we have already seen in Art. 103, according to Kepler"s Second Law, at this point the earth is furthest from the sun, being now at a distance of 94-1/2 millions of miles, and therefore its...o...b..tal velocity will be slowest at that part of its...o...b..t.
If it were absolutely at rest in s.p.a.ce, and simply revolving on its own axis, then the result would be that the moon would be circled round the earth in an orbit _M_ _C_ _F_ which is perfectly circular in form; but, as the earth is being carried along slowly through s.p.a.ce by the circulating Aether currents, this onward movement changes the circular orbit into an orbit of elliptic form.
[Ill.u.s.tration: Fig: 28.]
The eccentricity of the moon"s...o...b..t when the earth is at its aphelion, or furthest from the sun, is now at a minimum, for the simple reason that the earth is proceeding slowly through s.p.a.ce, owing to the decreased kinetic energy of the aetherial currents at the increased distance.
So that, at this point of the earth"s...o...b..t, the difference between the two axes of the moon"s...o...b..t will be the least, and its...o...b..t at that point will be the nearest approach to that of a circle. But, as we have already seen, as soon as the earth leaves this part of its...o...b..t, and begins to get nearer to the sun, it pa.s.ses into a part of the aetherial medium possessing greater kinetic energy, with the result that its own velocity is accelerated. Now what is the effect of this increased acceleration of the earth on the eccentricity of the orbit of the moon?
The earth"s rotation on its axis remains unaltered during this increasing orbital velocity, consequently the aetherial currents generated by the earth will remain uniform, and the moon will still be circled round the earth in the same period of about 28 days. But while the time of the moon"s revolution remains unaltered, the orbit that she has to describe is now increased owing to the increased orbital velocity of its central body, with the result, that by the time the earth gets to that part of its...o...b..t represented by point _D_, it is then two millions of miles nearer to the sun than at point _C_, and will be circled round the sun by the aetherial currents at a much greater rate. Therefore, the eccentricity of the moon"s...o...b..t is increased just in proportion to the increased velocity of the earth in its...o...b..t round the sun. By the time the earth has arrived at point _A_, when it is only a distance of about 91 millions of miles from the sun, it reaches the minimum distance, and is circled round at the decreased distance with its maximum velocity.
At this point, therefore, the eccentricity of the orbit of the moon will be at its greatest, and, if one revolution could be represented by an ellipse _E_ _G_ _H_, then that ellipse would be more elongated, and the difference between the two axes of the moon"s...o...b..t would be greater than at any other point of the earth"s...o...b..t.
Thus it can readily be seen that the eccentricity of the moon"s...o...b..t is primarily due to the different velocities of the central body, in this case the earth, as that body is carried round its central body, the sun.
Where the earth"s motion is slowest, there the eccentricity of the moon"s...o...b..t will be at a minimum; but where the earth"s velocity is greatest, there the eccentricity of the moon"s...o...b..t will be at a maximum.
Between this minimum and maximum velocity of the earth in its...o...b..t there is the constant increase or decrease in the eccentricity of the orbit of the moon; the eccentricity increasing as the orbital velocity of the central body increases, and decreasing as the orbital velocity of the earth decreases. A further fact has, however, to be taken into consideration, which is that the primary body about which the moon revolves is itself subject to the same eccentricity of its...o...b..t, and for similar reasons, as we shall see later on. So that when the eccentricity of the earth"s...o...b..t is at its greatest, then the moon"s...o...b..t will possess its greatest possible eccentricity, and as the eccentricity of the earth"s...o...b..t is dependent upon the orbital velocity of the sun, so the greatest possible eccentricity of the moon"s...o...b..t is indirectly connected and a.s.sociated with the sun"s motion through s.p.a.ce, which motion will now be considered.
ART. 107. _The Sun and Kepler"s First Law._--We have learned in the previous articles that Kepler"s Laws not only apply to planetary motion, but are equally applicable to the motion of all satellites as they revolve round their respective planets.
The question now confronts us, as to whether Kepler"s Laws are equally true in their application to the sun? Now the sun is one of the host of stars that move in the vast infinity of s.p.a.ce, and if it can be proved that Kepler"s Laws hold good in relation to one star, as they do in relation to all planets and satellites, then such a result will have a most important bearing upon the motions of other stars, and we shall be able to determine with some degree of exactness what are the motions and orbits by which all the stars in the universe are governed.
Sir Wm. Herschel first attacked the question as to whether the sun, like all the other stars, was in motion, and if in motion, what was the shape of its...o...b..t, and the laws which governed its...o...b..tal velocity.
We know that the sun is the centre of the solar system, and the question to be considered is, whether that system is circled round a controlling centre while the sun is at rest in s.p.a.ce, simply possessing its one axial rotation, or whether, like every planet and satellite, it is subject to two motions, an axial rotation and an orbital velocity through s.p.a.ce. Further, if it possesses an orbital velocity through s.p.a.ce, what is the cause of that orbital velocity?
It was due to the genius of Sir Wm. Herschel to first solve this problem, and by careful research he was able to determine that the sun, with all its attendant planets, was indeed moving through s.p.a.ce.
Not only did he discover this fact, but he also found out the direction in which the whole of our solar system was moving, as well as the velocity with which the general movement was performed. Herschel proved that the onward march of the solar system was in the direction of the constellation of Hercules, and that the velocity of the march of this system exceeds five miles per second, or 500,000 miles per day.
Thus we learn that the whole of our solar system, comprising the sun, with all its planets with their attendant satellites which circle round each planet, and the asteroids or minor planets, are bound together by the two forces, the centripetal and the centrifugal, while the system as a whole is urged on its way by some force or power through the realms of s.p.a.ce.