ASTRONOMY. 



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days and nights, and the different seasons in this 

 planet, will bear a considerable resemblance to 

 those we experience in our terrestrial sphere.* 



At his nearest approach to the earth, his dis 

 tance from us is about 50 millions of miles ; 

 and, at his greatest distance, he is about 240 

 millions of miles ; so that in the former case he 

 appears nearly 25 times larger than in the latter. 

 To a spectator in this planet, our earth will 

 appear, alternately, as a morning and evening 

 star, and will exhibit all the phases of the moon, 

 just as Venus does to us, but with a less degree 

 of apparent magnitude and splendour. A lumi 

 nous zone has been observed about the poles of 

 Mars, which is subject to successive changes. 

 Dr. Herschel supposes that it is produced by the 

 reflection of the sun s light from his frozen re 

 gions, and that the melting of these masses of 

 polar ice is the cause of the variation in its mag 

 nitude and appearance. This planet moves, in 

 its orbit, at the rate of fifty-five thousand miles 

 an hour. 



The new planets. Between the orbits of 

 Mars and Jupiter, four planetary bodies have 

 been lately discovered, accompanied with cir 

 cumstances somewhat different from those of the 

 other bodies which compose our system. They 

 are named Ceres, Pallas, Juno, and Vesta. 

 The planet Ceres was discovered at Palermo, 

 hi Sicily, by M. Piazzi, on the first day of the 

 present century. It is of a ruddy colour, and 

 appears abour the size of a star of the 8th magni 

 tude, and is consequently invisible to the naked 

 eye. It performs its revolution in 4 years and 7 

 months, at the distance of 260 millions of miles 

 from the sun, and is reckoned, by some astrono 

 mers, to be about 1624 miles in diameter, or 

 about half the diameter of Mercury. It appears 

 to be surrounded with a large dense atmosphere. 

 Pallas was discovered the following year, 

 namely, on the 28th of March, 1802, by Dr. 

 Olbers of Bremen. It is supposed to be about 

 2000 miles in diameter, or nearly the size of the 

 moon. It revolves about the sun in 4 years and 

 7 months, or nearly in the same time as Ceres, 

 at the distance of 266 millions of miles; and is 

 surrounded with a nebulosity or atmosphere, 

 above 400 miles in height, similar to that of 

 Ceres. The planet Juno was discovered on the 

 1st September, 1804, by Mr. Harding of Bre 

 men, its mean distance from the sun is about 

 253 millions of miles ; its revolution is comple 

 ted in 4 years and 130 days, and its diameter is 

 computed to be about 1425 miles. It is free 

 from the nebulosity which surrounds Pallas, and 

 is distinguished from all the other planets by the 



The inclination cf the earth s axis to the ecliptic, 

 or, in other words, to the plane of its annual orbit, 

 is 23 degrees and 25 minutes, which is the cause of 

 the diversity of seasons, and of the different length 

 of days and nights. Were the axis of the earth per 

 pendicular to its orbit, as is the case with the pla 

 ne* Jupiter, there would be no diversity of seasons. 



great eccentricity of its orbit : being, at its least 

 distance from the sun, only 189 millions of miles, 

 and at its greatest distance 316 millions. Vesta 

 was discovered by Dr. Olbers on the 29th 

 March, 1807. It appears like a star of the 5th 

 or 6th magnitude, and may sometimes be distin 

 guished by the naked eye. Its light is more in 

 tense and white than any of the other three, and 

 it is not surrounded with any nebulosity. It is 

 distant from the sun about 225 millions of miles, 

 and completes its revolution in 3 years and 240 

 days. Its diameter has not yet been accurately 

 ascertained ; but from the intensity of its light, 

 and other circumstances, it is concluded, that it 

 exceeds in magnitude both Pallas and Juno. 



These planetary globes present to our view a 

 variety of anomalies and singularities, which 

 appear incompatible with the regularity, pro 

 portion, and harmony which were formerly sup 

 posed to characterize the arrangements of the 

 solar system. They are bodies much smaller in 

 size than the other planets they revolve nearly 

 at the same distances from the sun, and perform 

 their revolutions in nearly the same periods 

 their orbits are much more eccentric, and have a 

 much greater degree of inclination^ the ecliptic, 

 than those of the old planets and, what is alto 

 gether singular, (except incase of comets,) their 

 orbits cross each other; so that there is & possibi 

 lity that two of these bodies might happen to in 

 terfere, and to strike each other, in the course of 

 their revolutions. The orbit of Ceres crosses 

 the orbit of Pallas. Vesta may sometimes be at 

 a greater distance from the sun than either Ceres, 

 Pallas or Juno, although its mean distance is less 

 than that of either of them, by several millions 

 of miles ; so that the orbit of Vesta crosses the 

 orbits of all the other three. From these and 

 other circumstances, it has, with a high degree 

 of probability, been concluded that these four 

 planets are the fragments of a large celestial body 

 which once revolved between Mars and Jupiter, 

 and which had been burst asunder by some im 

 mense irruptive force. This idea seems to have 

 occurred to Dr. Olbers after he had discovered 

 the planet Pallas, and he imagined that other 

 fragments might possibly exist. He concluded, 

 that, if they all diverged from the same point, 

 &quot; they ought to have two common points of re 

 union, or two nodes in opposite regions of the 

 heavens, through which all the planetary frag 

 ments must sooner or later pass.&quot; One of these 

 nodes he found to be in the constellation Virgo, 

 and the other in the Whale ; and it is a remark 

 able ( oincidence, that it was in the latter of 

 these regions that the planet Juno was discover 

 ed by Mr. Harding. In order to detect the re 

 maining fragments (if any existed) Dr. Olbers 

 examined, three times every year, all the small 

 stars in Virgo and the Whale ; and it was ac 

 tually in the consellation Virgo, that he dis 

 covered the planet Vesta. It is not unlikely 



