THE MAJOR PLANETS. 



237 



THE MAJOR PLANETS. 



PASSING across the wide space which intervenes between the minor planets 

 which, with the earth, circulate under the immediate wing of the sun, in the 

 midst of which space we encounter the strange spectacle of the ruins of a shat- 

 tered world, we arrive at the region of the system in which roll in silent maj- 

 esty the stupendous orbs of JUPITER, SATURN, and HERSCHEL, accompanied by 

 their gorgeous apparatus of multiplied moons, rings, and belts. The mind is pre- 

 pared to expect here another order of worlds, and it is not disappointed. The 

 first of these sublime globes which attracts our attention is that of JUPITER, 

 whose diameter is eighty-eight thousand miles, and whose bulk is fifteen hun- 

 dred times that of our own globe. The distance of this planet from the sun is 

 nearly five hundred millions of miles, and when our globe is nearest to it, it is 

 nearly four times more distant from us than the sun. Nevertheless, such is its 

 stupendous size that it subtends to the eye an angle of forty-five seconds, and 

 is, next to the sun and moon, the most brilliant object in the heavens. It has 

 in this respect the advantage over VENUS, that when nearest to us its illumi- 

 nated hemisphere is presented directly to the line of vision, and it is seen in 

 the meridian at midnight, when the entire absence of the sun's light so much 

 favors its apparent splendor. The orbit of the earth, which is included in that 

 of Jupiter, is so small, compared with that of the planet, that its illuminated 

 hemisphere, which is presented precisely to the sun, is always presented very 

 nearly to the earth. Jupiter, therefore, does not appear sensibly gibbous, and, 

 consequently, is always seen with a full face. 



The time which Jupiter takes to make his complete revolution round the 

 sun, is 4,333 days, being something less than twelve years. Such is the 

 length of the year of Jupiter. 



The weight or mass of the planet Jupiter is*316 times greater than that of the 

 earth ; but its bulk, being greater than that of the earth, in the higher propor- 

 tion of about fifteen hundred to one, it follows that its density is about four 

 times less than that of the earth ; being nearly equal to the density of the sun. 



