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of a considerable size ; 2. They move in not very excentric ellipses 

 round the sun ; 3. The planes of their orbits do not deviate many 

 degrees from the plane of the earth's orbit ; 4. Their motion is direct ; 

 5. They may have satellites or rings ; 6. They have an atmosphere 

 of considerable extent, which, however, bears hardly any sensible 

 proportion to their diameters ; and lastly, Their orbits are at certain 

 considerable distances from each other. 



These characters being next applied to the new stars, we find, in 

 the first place, that as to the magnitude, they can certainly not be 

 classed among planets ; since the least of these (Mercury) is no less 

 than 73,839 times larger than Pallas ; 2. Their motions may perhaps 

 agree sufficiently ; but 3. The planes of the orbits of the new stars 

 appear to deviate so much from that of the earth, that, were they 

 admitted into the number of planets, we should have to extend the 

 zodiac far beyond its present limits ; and as it is not improbable that 

 more of these bodies will be hereafter discovered, we shall perhaps 

 end in having no zodiac at all. As to the 4th article, The motion of 

 the new stars appears to be direct, like that of the planets. 5. Besides 

 that no satellites have as yet been discovered belonging to these new 

 stars, it may be inferred cl priori that they have not a sufficient mass 

 of matter to retain any. 6. The new stars, with respect to the small 

 comas they exhibit, differ widely from planets, and might rather be 

 classed among the comets, did not other circumstances militate 

 against this opinion ; and lastly, The orbits of the new stars are so 

 near each other, that the admitting them as planets would materially 

 affect the general harmony that takes place among the rest. As to 

 their being comets, the five following criteria are here given, by 

 which those desultory bodies have hitherto been distinguished : 

 1. They are generally of a very small size; 2. They move in very 

 excentric ellipses, or apparently parabolic arches round the sun ; 

 3. The direction of their motion is totally undetermined; 4. The 

 planes of their orbits admit of the greatest variety in their situation ; 

 and 5. They have atmospheres of very great extent, which show 

 themselves in various forms of tails, comas, haziness, &c. On apply- 

 ing these distinguishing characters to the new stars, we find, that as 

 to size, they might perhaps be classed with comets ; but that, as to 

 the nature of the curve in which they move, the direction of their 

 motion, and the planes of their orbits, they deviate still more from 

 comets than they do from planets ; and that, as to their atmosphere, 

 though they bear in this respect a greater resemblance to comets 

 than to planets, yet, upon a careful comparison with the appearances 

 of several comets observed of late years, it seems evident that they 

 are not entitled to a place among them ; the most considerable of 

 their comas being barely one-fiftieth part of the smallest that has 

 ever been observed to attend a comet. 



Thus it appears, that neither the appellation of planet nor comet 

 can be assigned to these newly discovered bodies. And it remains, 

 therefore, to find out some new term by which they may be distin- 

 guished. Previously to this, the author thinks it necessary to fix 



