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The beauty of the heavens : a pictorial display of the astronomical phenomena of the universe : one hundred and four coloured scenes illustrating a familiar lecture on astronomy / by Charles F. Blunt
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THE BEAUTY OF THE HEAVENS.

Herschel, in his discovery of this planet, which, in honour of the reigningmonarch, he named the Georgium Sidus ; by the astronomers of most foreigncountries it is called Herschel, after its discoverer ; by the astronomers ofPrussia, and some others, it is called Uranus : by this name it is now mostgenerally known.

Uranus appears to us about the size of a star of the smallest visible magni-tude, having a faint blue light; it may, occasionally, be discovered without thehelp of a telescope, in clear weather, and in the absence of the moon ; but thedisc appears distinct and well defined, when observed through a telescope mag-nifying two or three hundred times.

The scene represents, in the upper figure, a telescopic view of the planet,as seen with a great magnifying power. The small lower figures represent ourearth and moon, of the proportion their diameters bear to the planet Uranus , which,perhaps, makes a more satisfactory impression on the mind, of the dimensionsof this planet; and, with reference to its diminutive appearance in the heavens,gives a clearer idea of its vast distance than a statement in figures.

Uranus is accompanied by six satellites, all of which move round him nearlyat right angles to the plane of his orbit; whereas, the orbits of the satellites ofJupiter and Saturn are nearly in the same plane with the orbits of the planetsthemselves. The most remarkable phenomenon, however, exhibited by thesatellites of Uranus , is, that their motion is retrograde, or directly the reverse ofthat of the satellites of the other planets, and of the planets themselves, whichwe have shewn to be in a direction from west to east; whereas, the satellitesof Uranus move round him in a direction from east to west.

The first, or nearest satellite to the planet, is distant

from it .

The second.

The third .

The fourth.

The fifth.

The sixth .

230,330 miles.

298,830

348,390

399,590

746,240

1,597,700

Days. Hours. Min.

The nearest satellite revolves about the planet in ... 5 . 21 . 25

The second. 8.17.

The third. 10 . 23 . 4

The fourth . 13. 11. 5

The fifth. 38 . 2 .

The sixth.107 . 16 . 40

The satellites of Uranus were not discovered with the planet itself; thesecond and fourth were first seen six years after the discovery of the planet,vis. in 1787. The other four were discovered in 1790 and 1794.