Читать книгу Astronomy Explained Upon Sir Isaac Newton's Principles - James Ferguson - Страница 8
ОглавлениеHe has no change of seasons;
71. The Axis of Jupiter is so nearly perpendicular to his Orbit, that he has no sensible change of seasons; which is a great advantage, and wisely ordered by the Author of Nature. For, if the Axis of this Planet were inclined any considerable number of degrees, just so many degrees round each Pole would in their turn be almost six of our years together in darkness. And, as each degree of a great Circle on Jupiter contains 706 of our miles at a mean rate, it is easy to judge what vast tracts of land would be rendered uninhabitable by any considerable inclination of his Axis.
But has four Moons.
72. The Sun appears but 1⁄28 part so big to Jupiter as to us; and his light and heat are in the same small proportion, but compensated by the quick returns thereof, and by four Moons (some bigger and some less than our Earth) which revolve about him: so that there is scarce any part of this huge Planet but what is during the whole night enlightened by one or more of these Moons, except his Poles, whence only the farthest Moons can be seen, and where their light is not wanted, because the Sun constantly circulates in or near the Horizon, and is very probably kept in view of both Poles by the Refraction of Jupiter’s Atmosphere, which, if it be like ours, has certainly refractive power enough for that purpose.
Their periods round Jupiter.
Their grand period.
73. The Orbits of these Moons are represented in the Scheme of the Solar System by four small circles marked 1. 2. 3. 4. on Jupiter’s Orbit ♃; but are drawn fifty times too large in proportion to it. The first Moon, or that nearest to Jupiter, goes round him in 1 day 18 hours and 36 minutes of our time; and is 229 thousand miles distant from his center: The second performs it’s revolution in three days 13 hours and 15 minutes, at 364 thousand miles distance: The third in 7 days three hours and 59 minutes, at the distance of 580 thousand miles: And the fourth, or outermost, in 16 days 18 hours and 30 minutes, at the distance of one million of miles from his center. The Periods of these Moons are so incommensurate to one another, that if ever they were all in a right line between Jupiter and the Sun, it will require more than 3,000,000,000,000 years from that time to bring them all into the same right line again, as any one will find who reduces all their periods into seconds, then multiplies them into one another, and divides the product by 432; which is the highest number that will divide the product of all their periodical times, namely 42,085,303,376,931,994,955,904 seconds, without a remainder.
Parallax of their Orbits, and distances from Jupiter.
PLATE I.
How he appears to his nearest Moon.
74. The Angles under which the Orbits of Jupiter’s Moons are seen from the Earth, at it’s mean distance from Jupiter, are as follow: The first, 3ʹ 55ʺ; the second, 6ʹ 14ʺ; the third, 9ʹ 58ʺ; and the fourth, 17ʹ 30ʺ. And their distances from Jupiter, measured by his semidiameters, are thus: The first, 52⁄3; the second, 9; the third. 1423⁄60; and the fourth, 2518⁄60 [15]. This Planet, seen from it’s nearest Moon, appears 1000 times as large as our Moon does to us; waxing and waneing in all her monthly shapes, every 421⁄2 hours.
Two grand discoveries made by the Eclipse of Jupiter’s Moons.
75. Jupiter’s three nearest Moons fall into his shadow, and are eclipsed in every Revolution: but the Orbit of the fourth Moon is so much inclined, that it passeth by Jupiter, without falling into his shadow, two years in every six. By these Eclipses, Astronomers have not only discovered that the Sun’s light comes to us in eight minutes; but have also determined the longitudes of places on this Earth with greater certainty and facility than by any other method yet known; as shall be explained in the eleventh Chapter.
The great difference between the Equatoreal and Polar diameters
of Jupiter.
The difference little in those of our Earth.
76. The difference between the Equatoreal and Polar diameters of Jupiter is 6230 miles; for his equatoreal diameter is to his polar as 13 to 12. So that his Poles are 3115 miles nearer his center than his Equator is. This results from his quick motion round his Axis; for the fluids, together with the light particles, which they can carry or wash away with them, recede from the Poles which are at rest, towards the Equator where the motion is quickest, until there be a sufficient number accumulated to make up the deficiency of gravity occasioned by the centrifugal force, which always arises from a quick motion round an axis: and when the weight is made up so, as that all parts of the surface press equally heavy toward the center, there is an equilibrium, and the equatoreal parts rise no higher. Our Earth being but a very small Planet, compared to Jupiter, and it’s motion on it’s Axis being much slower, it is less flattened of course; for the difference between it’s equatoreal and polar diameters is only as 230 to 229, or 35 miles.
Place of his Nodes.
77. Jupiter’s Orbit is 1 degree 20 minutes inclined to the Ecliptic. His North Node is in the 7th degree of Cancer, and his South Node in the 7th degree of Capricorn.
Saturn.
Fig. I.
78. Saturn, the remotest of all the Planets, is about 777 millions of miles from the Sun; and, travelling at the rate of 18 thousand miles every hour, as in the circle marked ♄, performs his annual circuit in 29 years 167 days and 5 hours of our time; which makes only one year to that Planet. His diameter is 67,000 miles; and therefore he is near 600 times as big as the Earth.
Fig. V.
His Ring.
PLATE I.
79. He is surrounded by a thin broad Ring, as an artificial Globe is by its Horizon. This Ring appears double when seen through a good telescope, and is represented by the figure in such an oblique view as it is generally seen. It is inclined 30 degrees to the Ecliptic, and is about 21 thousand miles in breadth; which is equal to it’s distance from Saturn on all sides. There is reason to believe that the Ring turns round it’s Axis, because, when it is almost edge-wise to us, it appears somewhat thicker on one side of the Planet than on the other; and the thickest edge has been seen on different sides at different times. But Saturn having no visible spots on his body, whereby to determine the time of his turning round his Axis, the length of his days and nights, and the position of his Axis, are unknown to us.
His five Moons.
Fig. I.
80. To Saturn, the Sun appears only 1⁄90th part so big as to us; and the light and heat he receives from the Sun are in the same proportion to ours. But to compensate for the small quantity of sun-light, he has five Moons, all going round him on the outside of his Ring, and nearly in the same plane with it. The first, or nearest Moon to Saturn, goes round him in 1 day 21 hours 19 minutes; and is 140 thousand miles from his center: The second, in two days 17 hours 40 minutes; at the distance of 187 thousand miles: The third, in 4 days 12 hours 25 minutes; at 263 thousand miles distance: The fourth, in 15 days 22 hours 41 minutes; at the distance of 600 thousand miles: And the fifth, or outermost, at one million 800 thousand miles from Saturn’s center, goes round him in 79 days 7 hours 48 minutes. Their Orbits in the Scheme of the Solar System are represented by the five small circles, marked 1. 2. 3. 4. 5. on Saturn’s Orbit; but these, like the Orbits of the other Satellites, are drawn fifty times too large in proportion to the Orbits of their Primary Planets.
His Axis probably inclined to his Ring.
81. The Sun shines almost fifteen of our years together on one side of Saturn’s Ring without setting, and as long on the other in it’s turn. So that the Ring is visible to the inhabitants of that Planet for almost fifteen of our years, and as long invisible by turns, if it’s Axis has no Inclination to it’s Ring: but if the Axis of the Planet be inclined to the Ring, suppose about 30 degrees, the Ring will appear and disappear once every natural day to all the inhabitants within 30 degrees of the Equator, on both sides, frequently eclipsing the Sun in a Saturnian day. Moreover, if Saturn’s Axis be so inclined to his Ring, it is perpendicular to his Orbit; and thereby the inconvenience of different seasons to that Planet is avoided. For considering the length of Saturn’s year, which is almost equal to thirty of ours, what a dreadful condition must the inhabitants of his Polar regions be in, if they be half of that time deprived of the light and heat of the Sun? which must not be their case alone, if the Axis of the Planet be perpendicular to the Ring, but also the Ring must hide the Sun from vast tracks of land on each side of the Equator for 13 or 14 of our years together, on the south side and north side by turns, as the Axis inclines to or from the Sun: the reverse of which inconvenience is another good presumptive proof of the Inclination of Saturn’s Axis to it’s Ring, and also of his Axis being perpendicular to his Orbit.
How the Ring appears to Saturn and to us.
In what Signs Saturn appears to lose his Ring; and in what
Signs it appears most open to us.
82. This Ring, seen from Saturn, appears like a vast luminous Arch in the Heavens, as if it did not belong to the Planet. When we see the Ring most open, it’s shadow upon the Planet is broadest; and from that time the shadow grows narrower, as the Ring appears to do to us; until, by Saturn’s annual motion, the Sun comes to the plane of the Ring, or even with it’s edge; which being then directed towards us, becomes invisible on account of it’s thinness; as shall be explained more largely in the tenth Chapter, and illustrated by a figure. The Ring disappears twice in every annual Revolution of Saturn, namely, when he is in the 19th degree both of Pisces and of Virgo. And when Saturn is in the middle between these points, or in the 19th degree either of Gemini or of Sagittarius, his Ring appears most open to us; and then it’s longest diameter is to it’s shortest as 9 to 4.
No Planet but Saturn can be seen from Jupiter; nor any from Jupiter besides Saturn.
83. To such eyes as ours, unassisted by instruments, Jupiter is the only Planet that can be seen from Saturn; and Saturn the only Planet that can be seen from Jupiter. So that the inhabitants of these two Planets must either see much farther than we do, or have equally good instruments to carry their sight to remote objects, if they know that there is such a body as our Earth in the Universe: for the Earth is no bigger seen from Jupiter than his Moons are seen from the Earth; and if his large body had not first attracted our sight, and prompted our curiosity to view him with the telescope, we should never have known any thing of his Moons; unless by chance we had directed the telescope toward that small part of the Heavens where they were at the time of observation. And the like is true of the Moons of Saturn.
Place of Saturn’s Nodes.
84. The Orbit of Saturn is 21⁄2 degrees inclined to the Ecliptic, or Orbit of our Earth, and intersects it in the 21st degree of Cancer and of Capricorn; so that Saturn’s Nodes are only 14 degrees from Jupiter’s, § 77.
The Sun’s light much stronger on Jupiter and Saturn than is
generally believed.
All our heat depends not on the Sun’s rays.
85. The quantity of light, afforded by the Sun of Jupiter, being but 1⁄28th part, and to Saturn only 1⁄90th part, of what we enjoy; may at first thought induce us to believe that these two Planets are entirely unfit for rational beings to dwell upon. But, that their light is not so weak as we imagine, is evident from their brightness in the night-time; and also, that when the Sun is so much eclipsed to us as to have only the 40th part of his Disc left uncovered by the Moon, the decrease of light is not very sensible: and just at the end of darkness in Total Eclipses, when his western limb begins to be visible, and seems no bigger than a bit of fine silver wire, every one is surprised at the brightness wherewith that small part of him shines. The Moon when Full affords travellers light enough to keep them from mistaking their way; and yet, according to Dr. Smith[16], it is equal to no more than a 90 thousandth part of the light of the Sun: that is, the Sun’s light is 90 thousand times as strong as the light of the Moon when Full. Consequently, the Sun gives a thousand times as much light to Saturn as the Full Moon does to us; and above three thousand times as much to Jupiter. So that these two Planets, even without any Moons, would be much more enlightened than we at first imagine; and by having so many, they may be very comfortable places of residence. Their heat, so far as it depends on the force of the Sun’s rays, is certainly much less than ours; to which no doubt the bodies of their inhabitants are as well adapted as ours are to the seasons we enjoy. And if we consider, that Jupiter never has any winter, even at his Poles; which probably is also the case with Saturn, the cold cannot be so intense on these two Planets as is generally imagined. Besides, there may be something in their nature or soil much warmer than in that of our Earth: and we find that all our heat depends not on the rays of the Sun; for if it did, we should always have the same months equally hot or cold at their annual returns. But it is far otherwise, for February is sometimes warmer than May, which must be owing to vapours and exhalations from the Earth.
It is highly probable that all the Planets are inhabited.
PLATE I.
86. Every person who looks upon, and compares the Systems of Moons together, which belong to Jupiter and Saturn, must be amazed at the vast magnitude of these two Planets, and the noble attendance they have in respect of our little Earth: and can never bring himself to think, that an infinitely wise Creator should dispose of all his animals and vegetables here, leaving the other Planets bare and destitute of rational creatures. To suppose that he had any view to our Benefit, in creating these Moons and giving them their motions round Jupiter and Saturn; to imagine that he intended these vast Bodies for any advantage to us, when he well knew that they could never be seen but by a few Astronomers peeping through telescopes; and that he gave to the Planets regular returns of days and nights, and different seasons to all where they would be convenient; but of no manner of service to us, except only what immediately regards our own Planet the Earth; to imagine, I say, that he did all this on our account, would be charging him impiously with having done much in vain: and as absurd, as to imagine that he has created a little Sun and a Planetary System within the shell of our Earth, and intended them for our use. These considerations amount to little less than a positive proof that all the Planets are inhabited: for if they are not, why all this care in furnishing them with so many Moons, to supply those with light which are at the greater distances from the Sun? Do we not see, that the farther a Planet is from the Sun, the greater Apparatus it has for that purpose? save only Mars, which being but a small Planet, may have Moons too small to be seen by us. We know that the Earth goes round the Sun, and turns round it’s own Axis, to produce the vicissitudes of summer and winter by the former, and of day and night by the latter motion, for the benefit of its inhabitants. May we not then fairly conclude, by parity of reason, that the end and design of all the other Planets is the same? and is not this agreeable to that beautiful harmony which reigns over the Universe? Surely it is: and raises in us the most magnificent ideas of the SUPREME BEING, who is every where, and at all times present; displaying his power, wisdom, and goodness among all his creatures! and distributing happiness to innumerable ranks of various beings!
Fig. II.
How the Sun appears to the different Planets.
87. In Fig. 2d, we have a view of the proportional breadth of the Sun’s face or disc, as seen from the different Planets. The Sun is represented No 1, as seen from Mercury; No 2, as seen from Venus; No 3, as seen from the Earth; No 4, as seen from Mars; No 5, as seen from Jupiter; and No 6, as seen from Saturn.
Fig. III.
Fig. IV.
Let the circle B be the Sun as seen from any Planet, at a given distance; to another Planet, at double that distance, the Sun will appear just of half that breadth, as A; which contains only one fourth part of the area or surface of B. For, all circles, as well as square surfaces, are to one another as the squares of their diameters. Thus, the square A is just half as broad as the square B; and yet it is plain to sight, that B contains four times as much surface as A. Hence, in round numbers, the Sun appears 7 times larger to Mercury than to us, 90 times larger to us than to Saturn, and 630 times as large to Mercury as to Saturn.
Fig. V.
Proportional bulks and distances of the Planets.
PLATE I.
88. In Fig. 5th, we have a view of the bulks of the Planets in proportion to each other, and to a supposed globe of two foot diameter for the Sun. The Earth is 27 times as big as Mercury, very little bigger than Venus, 5 times as big as Mars; but Jupiter is 1049 times as big as the Earth, Saturn 586 times as big, exclusive of his Ring; and the Sun is 877 thousand 650 times as big as the Earth. If the Planets in this Figure were set at their due distances from a Sun of two feet diameter, according to their proportional bulks, as in our System, Mercury would be 28 yards from the Sun’s center; Venus 51 yards 1 foot; the Earth 70 yards 2 feet; Mars 107 yards 2 feet; Jupiter 370 yards 2 feet; and Saturn 760 yards two feet. The Comet of the year 1680, at it’s greatest distance, 10 thousand 760 yards. In this proportion, the Moon’s distance from the center of the Earth would be only 71⁄2 inches.
An idea of their distances.
89. To assist the imagination in conceiving an idea of the vast distances of the Sun, Planets, and Stars, let us suppose, that a body projected from the Sun should continue to fly with the swiftness of a cannon ball; i. e. 480 miles every hour; this body would reach the Orbit of Mercury, in 7 years 221 days; of Venus, in 14 years 8 days; of the Earth, in 19 years 91 days; of Mars, in 29 years 85 days; of Jupiter, in 100 years 280 days; of Saturn, in 184 years 240 days; to the Comet of 1680, at it’s greatest distance from the Sun, in 2660 years; and to the nearest fixed Stars in about 7 million 600 thousand years.
Why the Planets appear bigger and less at different times.
90. As the Earth is not the center of the Orbits in which the Planets move, they come nearer to it and go farther from it and at different times; on which account they appear bigger and less by turns. Hence, the apparent magnitudes of the Planets are not always a certain rule to know them by.
Fig. I.
91. Under Fig. 3, are the names and characters of the twelve Signs of the Zodiac, which the Reader should be perfectly well acquainted with; so as to know the characters without seeing the names. Every Sign contains 30 degrees, as in the Circle bounding the Solar System; to which the characters of the Signs are set in their proper places.
The Comets.
92. The Comets are solid opaque bodies, with long transparent trains or tails, issuing from that side which is turned away from the Sun. They move about the Sun, in very excentric ellipses; and are of a much greater density than the Earth; for some of them are heated in every Period to such a degree, as would vitrify or dissipate any substance known to us. Sir Isaac Newton computed the heat of the Comet which appeared in the year 1680, when nearest the Sun, to be 2000 times hotter than red-hot iron, and that being thus heated, it must retain it’s heat until it comes round again, although it’s Period should be more than twenty thousand years; and it is computed to be only 575. The method of computing the heat of bodies, keeping at any known distance from the Sun, so far as their heat depends on the force of the Sun’s rays, is very easy; and shall be explained in the eighth Chapter.
PLATE I.
Fig. I.
They prove that the Orbits of the Planets are not solid.
The Periods only of three are known.
They prove the Stars to be at immense distances.
93. Part of the Paths of three Comets are delineated in the Scheme of the Solar System, and the years marked in which they made their appearance. It is believed, that there are at least 21 Comets belonging to our System, moving in all sorts of directions: and all those which have been observed, have moved through the ethereal Regions and the Orbits of the Planets without suffering the least sensible resistance in their motions; which plainly proves that the Planets do not move in solid Orbs. Of all the Comets, the Periods of the above-mentioned three only are known with any degree of certainty. The first of these Comets appeared in the years 1531, 1607, and 1682; and is expected to appear again in the year 1758, and every 75th year afterwards. The second of them appeared in 1532 and 1661, and may be expected to return in 1789 and every 129th year afterwards. The third, having last appeared in 1680, and it’s Period being no less than 575 years, cannot return until the year 2225. This Comet, at it’s greatest distance, is about 11 thousand two hundred millions of miles from the Sun; and at it’s least distance from the Sun’s center, which is 490,000 miles, is within less than a third part of the Sun’s semi-diameter from his surface. In that part of it’s Orbit which is nearest the Sun, it flies with the amazing swiftness of 880,000 miles in an hour; and the Sun, as seen from it, appears an hundred degrees in breadth; consequently, 40 thousand times as large as he appears to us. The astonishing length that this Comet runs out into empty Space, suggests to our minds an idea of the vast distance between the Sun and the nearest fixed Stars; of whose Attractions all the Comets must keep clear, to return periodically, and go round the Sun; and it shews us also, that the nearest Stars, which are probably those that seem the largest, are as big as our Sun, and of the same nature with him; otherwise, they could not appear so large and bright to us as they do at such an immense distance.
Inferences drawn from the above phenomena.
94. The extreme heat, the dense atmosphere, the gross vapours, the chaotic state of the Comets, seem at first sight to indicate them altogether unfit for the purposes of animal life, and a most miserable habitation for rational beings: and therefore [17]some are of opinion that they are so many hells for tormenting the damned with perpetual vicissitudes of heat and cold. But, when we consider, on the other hand, the infinite power and goodness of the Deity; the latter inclining, and the former enabling him to make creatures suited to all states and circumstances; that matter exists only for the sake of intelligence; and that wherever we find it, we always find it pregnant with life, or necessarily subservient thereto; the numberless species, the astonishing diversity of animals in earth, air, water, and even on other animals; every blade of grass, every tender leaf, every natural fluid, swarming with life; and every one of these enjoying such gratifications as the nature and state of each requires: when we reflect moreover that some centuries ago, till experience undeceived us, a great part of the Earth was judged uninhabitable; the Torrid Zone by reason of excessive heat, and the two Frigid Zones because of their intollerable cold; it seems highly probable, that such numerous and large masses of durable matter as the Comets are, however unlike they be to our Earth, are not destitute of beings capable of contemplating with wonder, and acknowledging with gratitude the wisdom, symmetry, and beauty of the Creation; which is more plainly to be observed in their extensive Tour through the Heavens, than in our more confined Circuit. If farther conjecture is permitted, may we not suppose them instrumental in recruiting the expended fuel of the Sun; and supplying the exhausted moisture of the Planets? However difficult it may be, circumstanced as we are, to find out their particular destination, this is an undoubted truth, that wherever the Deity exerts his power, there he also manifests his wisdom and goodness.
This System very ancient, and demonstrable.
95. THE SOLAR SYSTEM here described is not a late invention; for it was known and taught by the wise Samian philosopher Pythagoras, and others among the ancients; but in latter times was lost, ’till the 15th century, when it was again restored by the famous Polish philosopher Nicholaus Copernicus, who was born at Thorn in the year 1473. In this, he was followed by the greatest mathematicians and philosophers that have since lived; as Kepler, Galileo, Descartes, Gassendus, and Sir Isaac Newton; the last of whom has established this System on such an everlasting foundation of mathematical and physical demonstration, as can never be shaken: and none who understand him can hesitate about it.
The Ptolemean System absurd.
96. In the Ptolemean System the Earth was supposed to be fixed in the Center of the Universe; and that the Moon, Mercury, Venus, the Sun, Mars, Jupiter, and Saturn moved round the Earth: above the Planets, this Hypothesis placed the Firmament of Stars, and then the two Crystalline Spheres; all which were included in and received motion from the Primum Mobile, which constantly revolved about the Earth in 24 hours, from East to West. But as this rude Scheme was found incapable to stand the test of art and observation, it was soon rejected by all true philosophers; notwithstanding the opposition and violence of blind and zealous bigots.
The Tychonic System, partly true and partly false.
97. The Tychonic System succeeded the Ptolemean, but was never so generally received. In this the Earth was supposed to stand still in the Center of the Universe or Firmament of Stars, and the Sun to revolve about it every 24 hours; the Planets, Mercury, Venus, Mars, Jupiter, and Saturn, going round the Sun in the times already mentioned. But some of Tycho’s disciples supposed the Earth to have a diurnal motion round it’s Axis, and the Sun with all the above Planets to go round the Earth in a year; the Planets moving round the Sun in the foresaid times. This hypothesis, being partly true and partly false, was embraced by few; and soon gave way to the only true and rational System, restored by Copernicus and demonstrated by Sir Isaac Newton.
98. To bring the foregoing particulars at once in view, with several others which follow, concerning the Periods, Distances, Bulks, &c. of the Planets, the following Table is inserted.
A TABLE
Of the PERIODS, REVOLUTIONS, MAGNITUDES, &c. of the PLANETS.
| Sun and Planets. | Annual period round the Sun. | Diurnal rotation on it’s Axis. | Diameter in English miles. | Mean diam. as seen fr. the Sun. | Mean distance from the Sun in English miles. |
|---|---|---|---|---|---|
| Sun | ---- | 25d. 6h. | 763000 | ---- | ---- |
| Mercury | 87d 23h | Unknown. | 2600 | 20ʺ | 32,000,000 |
| Venus | 224d 17h | 24d. 8h. | 7906 | 30ʺ | 59,000,000 |
| Earth | 365d 6h | 1d. 0h. | 7970 | 21ʺ | 81,000,000 |
| Moon | 365d 6h | 29d. 123⁄4h. | 2180 | 6ʺ | 81,000,000 |
| Mars | 686d 23h | 24h. 40m. | 4444 | 11ʺ | 123,000,000 |
| Jupiter | 4332d 12h | 9h. 56m. | 81000 | 37ʺ | 424,000,000 |
| Saturn | 10759d 7h | Unknown. | 67000 | 16ʺ | 777,000,000 |
| Sun and Planets. | Excentricity of it’s Orbit in miles. | Axis inclined to Orbit. | Orbit inclined to Ecliptic. | Place of it’s Aphelion. | Place of it’s Ascending Node. | Proportion of Diameters. |
|---|---|---|---|---|---|---|
| Sun | ---- | 8° 0ʹ | ---- | ---- | ---- | 10000 |
| Mercury | 6,720,000 | Unkn. | 6° 54ʹ | ♐ 13° 8ʹ | ♉ 14° 43ʹ | 341⁄10 |
| Venus | 413,000 | 75° 0ʹ | 3° 20ʹ | ♒ 4° 20ʹ | ♊ 13° 59ʹ | 1031⁄2 |
| Earth | 1,377,000 | 23° 29ʹ | 0° 0ʹ | ♑ 8° 1ʹ | ---- | 1041⁄2 |
| Moon | 13,000 | 2° 10ʹ | 5° 8ʹ | ---- | Variable. | 281⁄2 |
| Mars | 11,439,000 | 0° 0ʹ | 1° 52ʹ | ♍ 0° 32ʹ | ♉ 17° 17ʹ | 581⁄6 |
| Jupiter | 20,352,000 | 0° 0ʹ | 1° 20ʹ | ♎ 9° 10ʹ | ♋ 7° 29ʹ | 10612⁄3 |
| Saturn | 42,735,000 | Unkn. | 2° 30ʹ | ♐ 27° 50ʹ | ♋ 21° 13ʹ | 8781⁄9 |
| Sun and Planets. | Proportion of Bulk. | Prop. of Gravity on the surface. | Proportion of Density. | Proportion of Light & Heat. | Propor. quantity of Matter. | Hourly motion in it’s Orbit. | Hourly motion of it’s Equator. |
|---|---|---|---|---|---|---|---|
| Sun | 877650 | 24 | 251⁄2 | 45000 | 227500 | ---- | 3818 |
| Mercury | 1⁄27 | Unkn. | Unkn. | 61⁄2 | Unkn. | 95000 | Unkn. |
| Venus | 1 | Unkn. | Unkn. | 13⁄4 | Unkn. | 69000 | 43 |
| Earth | 1 | 1 | 100 | 1 | 1 | 58000 | 1042 |
| Moon | 1⁄50 | 34⁄100 | 1231⁄2 | 1 ± | 1⁄40 | 2290 | 91⁄2 |
| Mars | 1⁄5 | Unkn. | Unkn. | 3⁄7 | Unkn. | 47000 | 556 |
| Jupiter | 1049 | 2 | 19 | 1⁄28 | 220 | 25000 | 25920 |
| Saturn | 586 | 11⁄2 | 15 | 1⁄90 | 94 | 18000 | Unkn. |
| Sun and Planets. | Square miles in surface. | Cubic miles in solidity. | Would fall to the Sun in |
|---|---|---|---|
| Sun | 1,828,911,000,000 | 232,577,115,137,000,000 | days h. |
| Mercury | 21,236,800 | 9,195,534,500 | 1513 |
| Venus | 691,361,300 | 258,507,832,200 | 3917 |
| Earth | 199,852,860 | 265,404,598,080 | 1410 |
| Moon | 14,898,750 | 5,408,246,000 | 6410 |
| Mars | 62,038,240 | 45,969,335,840 | 1210 |
| Jupiter | 20,603,970,000 | 278,153,595,000,000 | 2900 |
| Saturn | 14,102,562,000 | 155,128,182,000,000 | 7670 |
| If the projectile force was destroyed. |
If the Moon’s projectile force was destroyed, she would fall to the Earth in 4 days 21 hours.
| Jupiter’s Moons. | Periods round Jupiter. | ||
|---|---|---|---|
| No | D. | H. | M. |
| 1 | 1 | 18 | 36 |
| 2 | 3 | 13 | 15 |
| 3 | 7 | 3 | 59 |
| 4 | 16 | 18 | 30 |
| Saturn’s Moons. | Periods round Saturn. | ||
|---|---|---|---|
| No | D. | H. | M. |
| 1 | 1 | 21 | 19 |
| 2 | 2 | 17 | 40 |
| 3 | 4 | 12 | 25 |
| 4 | 15 | 22 | 41 |
| 5 | 79 | 7 | 48 |
