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received Piazzi's letters, the newly-discov- | been so long unsuccessful in their labours ; ered planet had become lost to view, having and on the last day of the year the planet already approached that part of the heavens was detected by De Lach close to the place in which the sun was situated, and being assigned to it by the ephemeris of Gauss. thus lost to sight through the overpowering Thus, by a singular coincidence, the disbrilliancy of the solar light.

covery of the new planet was the work of Nothing remained for the present but to exactly one year. Detected on the evenawait the re-appearance of the missing orb. ing of the first day of the present century, Six long months, however, were to elapse, the stranger was finally admitted into the and all this time the stranger would be family of planets at the end of the first speeding onward in an orbit of which so year of the century. On January 1st, little was known, that it seemed all but 1802, the new planet was independently hopeless that the place of the new planet re-discovered by Olbers. The name Ceres should be guessed at after so long an inter- was assigned to it. val. In the meantime a rough analysis was On a careful examination of the orbit of made of the stranger's path, and all agreed Ceres, a very satisfactory accordance with in the conclusion that Kepler's prediction the anticipations of astronomers was found had really been fulfilled, and that the new to result. On the supposition that the planet revolved in an orbit intermediate earth's distance from the orbit of Mercury between the orbits of Mars and Jupiter. is expressed by two, the distance of Ceres Not only was this found to be the case, but should have been eight : it is actually seven it was shown that the distance of the stran- and nine-tenths. ger corresponded very closely with the law But it was not long before some very which has been stated above.

anomalous features were observed in the In September, 1801, the search for the relations presented by the new planet. In returning planet was commenced. But, the first place, it was found to be a very as had been feared, it proved unfruitful. minute object, not merely in comparison Again and again the keenest observers with the primary planets, but even when scrutinised those regions of the sky in compared with their satellites. Sir W. which the stranger might be expected to Herschel estimated its diameter at only 161 appear, but no success rewarded their la- miles; so that the surface of the new bours. “ The world began to sneer," world (assuming this estimate to be corwrites a modern'astronomer, “ at a science rect) is considerably less than that of which could find a body in the heavens and Great Britain. Then, again, the motion of then lose it for ever."

the new planet is not of the orderly nature Observational astronomy had been tried which is characteristic of the planetary sysand had failed - the time had come to tem. It travels in a path which is considapply the powers of physical astronomy. erably inclined to that plane in space near The young astronomer, Gauss, already well- wbich all the other planets are observed to known for his application of new modes of move. analysis to the computation of cometic or- While astronomers were speculating on bits, was fired with the ambition of com- these peculiarities, a new discovery was efpleting by means of computation the track- fected. The astronomer Olbers, during ing process which Piazzi had pursued by his search after Ceres, had familiarised actual observation, and had been com- himself with the aspect of all the telescopic pelled to leave unfinished.

stars which lie near the path followed by The attempt was a bold one - almost as that planet. On the 28th of March, 1802, bold as that later effort which led to the while examining a portion of this track discovery of distant Neptune. It was suc- region very near to the spot on which he cessful, however. The long process of had detected Ceres three months before calculation was finished a few days before he observed a small star of the seventh the end of the year 1801; the calculated magnitude where no star, he felt sure, had path of the planet on the celestial sphere been seen by him on any former occasion. was announced to the observers who had Now there is nothing very uncommon in

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such an observation as this, because there the massive globe of a primary planet into are many stars which only shine out at in- fragments, and hurled these forth with suftervals. Olbers supposed the stranger to ficient energy to account for the anomalous be one of these fitful variables ; but he motions of the recently discovered bodies. thought it well to re-examine the star, after He suggested the possibility that other an interval, in order to see whether it had fragments might be discovered; and he any perceptible motion. He found that it pointed out two parts of the heavens in was moving, and continuing his observa- which the search after such fragments would tions he established the fact that the stran- have the best chance of success. ger was a planet, on the very evening on The views of Olbers were quickly acted which he had first discovered it.

upon, and no very long time elapsed beIn exactly one month from the discovery fore the discovery of a third planet in one of this second planet, Gauss had calcu- of the very regions indicated by Olbers, lated its orbit. To the surprise of the as- seemed to confirm his fanciful theory. tronomical world, the stranger was found The new planet, which received the name to be quite as fitting a representative of of Juno, was detected by Harding, of LilienKepler's missing planet as Ceres had been thal, on September 2nd, 1804. It appears shown to be. Its mean distance is nearly to be smaller than either of the others, and the same as that of Ceres; and its dimen- revolves in an orbit of singular eccentricsions appear to be equally, or perhaps ity. more minute. But the orbit of the new Confirmed in his views by this discovery, planet presents one or two peculiarities. Olbers prosecuted the search after new It is far more eccentric than that of Ceres, fragments of his shattered planet with new and it departs so widely from the mean energy. For two years and a half, howplane of the planetary system, that Sir W. ever, he sought in vain. At length, on Herschel considered the term planet inap- March 28th, 1807, his perseverance met plicable to such a body. Hence arose the with its reward, in the discovery of the larginvention of the name asteroid, perhaps as est known member of the asteroidal family. ill-chosen a term as has ever been adopted He was examining the northern wing of by the scientific world.

Virgo, when his attention was drawn to a The circumstance that two planets should brilliant star of the sixth magnitude in a be found revolving around the sun at near- neighbourhood with which his long-continly the same mean distance, attracted a ued researches had made him intimately great deal of attention among astronomers. familiar. He had never before seen this În fact, we may look upon the discovery star, and, therefore, felt convinced that it as one of the most remarkable that has was a planet. It must be remembered that ever been effected. For men began at to a telescopist, sixth magnitude stars hold once to see that there exists within the sol- much the same position as first magnitude ar system a variety of structure of which stars to the naked-eye observer. They they had hitherto had little conception. shine out in the field of view just as ArctuIt is not saying too much to assert that a rus, Aldeboran, or Sirius shine out among large proportion of the views at present the lesser stars on the celestial vault. held respecting the planetary system would Therefore, a telescopist who has spent any have been scouted as bizarre and fanciful time in examining a particular region of the before the discovery of Pallas. For in as- heavens, would be as much struck by the tronomy, as in the other sciences, the discovery of a new sixth magnitude star, as range of the known limits man's concep- any person familiar with the constellations tions respecting the unknown.

would be if a new and brilliant star were to So strange did the phenomena presented shine out in some well-known star-group. by the two new planets appear, that as

A few hours' observation sufficed to place tronomers were led to suppose that possi- the planetary character of the star beyond a bly these bodies might be but the fraginents doubt. Soon after, Olbers sent to Gauss of a large planet, which had once revolved, a series of observations for the determinabrilliant as Mars or Jupiter, between the tion of the new planet's path, and in two orbits of these planets. "Men recalled the hours from the receipt of Olbers' communifanciful views of the ancient astronomer, cation, Gauss had completed the calculation who spoke of planets which had disap- - an achievement unexampled in the hispeared from the heavens. Olbers, the dis- tory of physical astronomy. The orbit of coverer of Pallas, was the first to give form the new planet was found to resemble that to the new theory. He supposed that of Ceres, Pallas, and Juno, but its distance some internal convulsion might have rent is somewhat smaller. It is the only asteroid which has ever been visible to the nak-four days later, M. Gasparis, of Naples, ed eye, Schroeter being the only observer detected the same asteroid. Within a year, who has so seen it.

M. Gasparis had his revenge, however. Then for a long time the progress of dis- On the 18th of January, 1852, Mr. Hind covery ceased. It would seem that no fur- marked down in the ecliptical chart which ther scarch was made until about the year he was compiling, with the aid of Mr. Bish1830, when M. Hencke, an amateur astron- op's refractor, at the Regent's Park Obseromer of Driessen, in Germany, began a vatory, a star of the eleventh magnitude. careful survey of the zodiac belt. For fif-Cloudy weather prevented him from re-exteen years he continued to examine the amining this object for exactly two months. heavens without success. During all those On the evening of March 18th, he turned long years he was intent on the study of his telescope to the spot which had been ocstars which no unaided eye has ever seen. cupied by the small star; but the star bad Laboriously he traced down their configura- vanished. Immediately he instituted a tion, returning again and again to star- searching scrutiny for the missing object, group after star-group in hopes of detecting and would probably soon have detected it. the signs of change.

But it was not until But, while the search was in progress, news the close of the year 1845, more than thirty- came of the discovery of an asteroid, in eight years after the discovery of Vesta, this particular region of the heavens, by M. that Hencke's unflinching perseverance met Gasparis. Professor Gauss was able to with its just reward. On the 8th of Decem- show that this object must on January 18th ber, he wrote to M. Encke, of the Observa- have occupied the exact place in which tory of Berlin, anno

nouncing the discovery of Hind had seen a telescopic star. In this a star in a certain position which he felt case, although Hind had not been able to sure had hitherto been untenanted. Encke detect the missing object, he would have examined the heavens in this neighbourhood been credited with the discovery of a new six days later, with the magnificent refrac-planet had he missed the starone day earlier. tor of the Berlin observatory, and quickly As it was, De Gasparis, having detected discovered a star which was not marked in the planet on the 17th of March (one day the observatory chart. As in former in- before Hind suspected its planetary nature), stances the planetary nature of the stranger, is entitled to the credit of the discovery: and the fact that it belongs to the same re- The planet, Amphitrite, was detected ingion of space already assigned to the other dependently by three observers, on three asteroids, were quickly established. Encke successive days, viz., by Mr. Marth, at the left the choice of a name with Hencke, who Regent's Park Observatory, on March 1st, selected the name Astræa.

1854; by Mr. Pogson, at Oxford, on March With the discovery of another planet by 2nd; and by M. Chacornac, at Marseilles, M. Hencke, in July, 1847, may be said to on March 3rd. have begun the long series of additions to The discovery of the planet Melese was the planetary system, which has continued attended by circumstances of singular inwithout interruption up to the present time. terest. M. Goldschmidt was engaged at Not one year has passed without the dis- Paris in searching for the planet Daphne. covery of at least one asteroid, and in every This planet had been discovered by him in year, except five, three asteroids and up- 1856, but was so unfavourably situated at wards have been detected. In 1852, eight the time of its discovery that only four were discovered; in 1857, nine; and in views were obtained of it, and the true na1861, no less than ten — the largest number ture of its path remained doubtful. Goldever yet detected in a single year.

schmidt, making use of a roughly calculated There is so little variety in the records ephemeris of the planet's motion, was scruof the discovery of asteroids, that it would tínizing the sky for Daphne, when he debe extremely wearisome to our readers if tected a minute star, which presently turned we were to give an account of the detection of out to be in motion. He announced his all or even of many of the asteroids. But discovery, and the planet, which every one some incidents in the progress of discovery supposed to be Daphne, was carefully have been well worthy of notice.

tracked by experienced observers. HowIn some instances, so closely have the ever, when its orbit was calculated, it beheavens been scrutinized by observers in came clear that there was some mistake. different places, that the same asteroid has The planet just discovered had doubtless been detected independently by two observ- been very near the place occupied by crs within a few days or hours of each other. Daphne in 1856, but not at the precise For instance, Mr. Hind detected Irene on point indicated by M. Goldschmidt's obthe night of the 19th of May, 1851, and, I servations. A careful computation soon such an observation as this, because there the massive globe of a primary planet into are many stars which only shine out at in- fragments, and hurled these forth with suftervals. Olbers supposed the stranger to ficient energy to account for the anomalous be one of these fitful variables; but he motions of the recently discovered bodies. thought it well to re-examine the star, after He suggested the possibility that other an interval, in order to see whether it had fragments might be discovered; and be any perceptible motion. He found that it pointed out two parts of the heavens in was moving, and continuing his observa- which the search after such fragments would tions he established the fact that the stran- have the best chance of success. ger was a planet, on the very evening on The views of Olbers were quickly acted which he had first discovered it.

upon, and no very long time elapsed beIn exactly one month from the discovery fore the discovery of a third planet in one of this second planet, Gauss had calcu- of the very regions indicated by Olbers, lated its orbit. To the surprise of the as- seemed to confirm his fanciful theory. tronomical world, the stranger was found The new planet, which received the name to be quite as fitting a representative of of Juno, was detected by Harding, of LilienKepler's missing planet as Ceres had been thal, on September 2nd, 1804. It appears shown to be. Its mean distance is nearly to be smaller than either of the others, and the same as that of Ceres; and its dimen- revolves in an orbit of singular eccentricsions appear to be equally, or perhaps ity. more minute. But the orbit of the new Confirmed in his views by this discovery, planet presents one or two peculiarities. Olbers prosecuted the search after new It is far more eccentric than that of Ceres, fragments of his shattered planet with new and it departs so widely from the mean energy. For two years and a half, howplane of the planetary system, that Sir W. ever, he sought in vain. At length, on Herschel considered the term planet inap- March 28th, 1807, his perseverance met plicable to such a body. Hence arose the with its reward, in the discovery of the larginvention of the name asteroid, perhaps as est known member of the asteroidal family: ill-chosen a term as has ever been adopted He was examining the northern wing of by the scientific world.

Virgo, when his attention was drawn to a The circumstance that two planets should brilliant star of the sixth magnitude in a be found revolving around the sun at near- neighbourhood with which his long-continly the same mean distance, attracted a ued researches had made him intimately great deal of attention among astronomers. familiar. He had never before seen this In fact, we may look upon the discovery star, and, therefore, felt convinced that it as one of the most remarkable that has was a planet. It must be remembered that ever been effected. For men began at to a telescopist, sixth magnitude stars hold once to see that there exists within the sol- much the same position as first magnitude ar system a variety of structure of which stars to the naked-eye observer. They they had hitherto had little conception. shine out in the field of view just as ArctuIt is not saying too much to assert that a rus, Aldeboran, or Sirius shine out among large proportion of the views at present the lesser stars on the celestial vault. held respecting the planetary system would Therefore, a telescopist who has spent any have been scouted as bizarre and fanciful time in examining a particular region of the before the discovery of Pallas. For in as- heavens, would be as much struck by the tronomy, as in the other sciences, the discovery of a new sixth magnitude star, as range of the known limits man's concep- any person familiar with the constellations tions respecting the unknown.

would be if a new and brilliant star were to So strange did the phenomena presented shine out in some well-known star-group. by the two new planets appear, that as- A few hours' observation sufficed to place tronomers were led to suppose that possi- the planetary character of the star beyond a bly these bodies might be but the fraginents doubt. Soon after, Olbers sent to Gauss of a large planet, which had once revolved, a series of observations for the determinabrilliant as Mars or Jupiter, between the tion of the new planet's path, and in two orbits of these planets. "Men recalled the hours from the receipt of Olbers' communifanciful views of the ancient astronomer, cation, Gauss had completed the calculation who spoke of planets which had disap- an achievement unexampled in the hispeared from the heavens. Olbers, the dis- tory of physical astronomy. The orbit of coverer of Pallas, was the first to give form the new planet was found to resemble that to the new theory. He supposed that of Ceres, Pallas, and Juno, but its distance some internal convulsion might have rent is somewhat smaller. It is the only asteroid which has erer been visible to the nak- four days later, M. Gasparis, of Naples, ed eye, Schroeter being the only observer detected the same asteroid. Within a year, who has so seen it.

M. Gasparis had his revenge, however. Then for a long time the progress of dis- On the 18th of January, 1852, Mr. Hind covery ceased. It would seem that no fur- marked down in the ecliptical chart which ther search was made until about the year he was compiling, with the aid of Mr. Bish1830, when M. Hencke, an amateur astron- op's refractor, at the Regent's Park Obseromer of Driessen, in Germany, began a vatory, a star of the eleventh magnitude. careful survey of the zodiac belt. For fif-Cloudy weather prevented him from re-exteen years he continued to examine the amining this object for exactly two months. heavens without success. During all those On the evening of March 18th, he turned long years he was intent on the study of his telescope to the spot which had been ocstars which no unaided eye has ever seen. cupied by the small star; but the star bad Laboriously he traced down their configura- vanished. Immediately he instituted a tion, returning again and again to star- searching scrutiny for the missing object, group after star-group in hopes of detecting and would probably soon have detected it. the signs of change. But it was not until But, while the search was in progress, news the close of the year 1845, more than thirty- came of the discovery of an asteroid, in eight years after the discovery of Vesta, this particular region of the heavens, by M. that Hencke's unflinching perseverance met Gasparis. Professor Gauss was able to with its just reward. On the 8th of Decem- show that this object must on January 18th ber, he wrote to M. Encke, of the Observa- have occupied the exact place in which tory of Berlin, announcing the discovery of Hind had seen a telescopic star. In this a star in a certain position which he felt case, although Hind had not been able to sure had hitherto been untenanted. Encke detect the missing object, he would have examined the heavens in this neighbourhood been credited with the discovery of a new six days later, with the magnificent refrac- planet had he missed the star one day earlier. tor of the Berlin observatory, and quickly As it was, De Gasparis, having detected discovered a star which was not marked in the planet on the 17th of March (one day the observatory chart. As in former in- before Hind suspected its planetary nature), stances the planetary nature of the stranger, is entitled to the credit of the discovery, and the fact that it belongs to the same re- The planet, Amphitrite, was detected ingion of space already assigned to the other dependently by three observers, on three asteroids, were quickly established. Encke successive days, viz., by Mr. Marth, at the left the choice of a name with Hencke, who Regent's Park Observatory, on March 1st, selected the name Astræa.

1854; by Mr. Pogson, at Oxford, on March With the discovery of another planet by 2nd; and by M. Chacornac, at Marseilles, M. Hencke, in July, 1847, may be said to on March 3rd. have begun the long series of additions to The discovery of the planet Melese was the planetary system, which has continued attended by circumstances of singular inwithout interruption up to the present time. terest.

M. Goldschmidt was engaged at Not one year has passed without the dis- Paris in searching for the planet Daphne. covery of at least one asteroid, and in every This planet had been discovered by him in year, except five, three asteroids and up- 1856, but was so unfavourably situated at wards have been detected. In 1852, eight the time of its discovery that only four were discovered; in 1857, nine; and in views were obtained of it, and the true na1861, no less than ten -- the largest number ture of its path remained doubtful. Goldever yet detected in a single year.

schmidt, making use of a roughly calculated There is so little variety in the records ephemeris of the planet's motion, was scruof the discovery of asteroids, that it would tinizing the sky for Daphne, when he debe extremely wearisome to our readers if tected a minute star, which presently turned we were to give an account of the detection of out to be in motion. He announced his all or even of many of the asteroids. But discovery, and the planet, which every one some incidents in the progress of discovery supposed to be Daphne, was carefully have been well worthy of notice.

tracked by experienced observers. HowIn some instances, so closely have the ever, when its orbit was calculated, it beheavens been scrutinized by observers in came clear that there was some mistake. different places, that the same asteroid has The planet just discovered had doubtless been detected independently by two observ- been very near the place occupied by crs within a few days or hours of each other. Daphne in 1856, but not at the precise For instance, Mr. Hind detected Irene on point indicated by M. Goldschmidt's obthe night of the 19th of May, 1851, and, I servations. A careful computation soon

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