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Incl. Long. Per.
2° 9' 852° 45' 7 52 215 57 12 10 SO 0
7 51 254 42 20 49
168 41 7 29 155 57 11 50 109 12 1 28 835 10 8 51 56 49
2.5357 2.9901 2.7834
more were detected in 1876, making the present number 168. Coronis, No. 158, was discovered by Dr. Knorre, of the Berlin Observa
2.9807 tory, on the 5th of January. Its distance from the sun is 2.99, and it shines with the light of 152 a star of the 11th or 12th magnitude. No. 159, Æmilia, was detected by Paul Henry, of 156 Xantippe.
3.0375 15 17 the Paris Observatory, January 26th. Una, 157 Dejanira the 160th of the group, was found by Dr. Peters, of Hamilton College, Clinton, N. Y., February 20th. It is of the 11th magnitude. Saturn and his Rings.—The American JourNo. 161 was first seen on the 19th of April, by nal of Science for June, 1876, contains an inProf. Watson, of Ann Arbor, Mich. The 162d teresting paper by L. Trouvelót on some physwas discovered on the 22d of April, by Prof. ical observations of the planet Saturn. The Henry, of Paris. M. Perrotin, of Toulouse, observations of Mr. Trouvelot were continued detected No. 163 on the 26th of April. Its through several years, and were made with the light is not greater than that of a star of the fifteen-inch refractor of the Harvard College 12th magnitude. The 164th of the cluster was Observatory, the twenty-six-inch refractor of discovered by M. Paul Henry, at Paris, July the Washington Observatory, and the six-inch 12th. It is of the 12th or 13th magnitude. refractor of his own observatory at Cambridge. Nos. 165, 166, and 167, which have received The ring exterior to the principal division has the names of Loreley, Rhodope, and Urda, been always seen under favorable circumstances were discovered on the 9th, 15th, and 28th to be divided into two sections by a narrow, of August, by Dr. Peters, of Clinton, N. Y. grayish line, called “the pencil-line." Thie The first two are of the 11th magnitude; the dusky ring, discovered by Bond, does not aplast, of the 12th. Urda is the 26th member pear to be separated from the old interior ring of the group first seen by the Director of the by any break or chasm. Designating the anClinton Observatory. No. 168 was discovered nulus exterior to the pencil line by A, that beby Prof. Watson, at Ann Arbor, Mich., on tween the pencil line and the principal division the 28th of September. This planet is of by B, and the outer portion of the interior ring the 11th magnitude, and is the 19th detected by C, Mr. Trouvelot's observations showby Prof. Watson. The supposed discovery of another member of the group on the 28th of the outer border of the principal division, has shown,
1. That the inner margin of the ring B, limiting September by Prof. Henry, of Paris, proved on the ansæ, some singular dark angular forms, which to be a rediscovery of Maia, No. 66, which may be attributed to an irregular and jagged conforhad been wholly lost sight of for several mation of the inner border of the ring B, either per
manent or temporary. years. The name of No. 139, discovered by Prof. shown a mottled or clouded appearance on the ansæ
2. That the surface of the rings A, B, and C, has Watson while at Peking, was erroneously during the last four years. given in a former volume. The Chinese name 3. 'That the thickness of the system of rings is selected by the discoverer is Juewa. Most increasing from the inner margin of the dusky ring members of the group discovered in 1875 are
to the outer border of the ring C, as proved by the
forın of the shadow of the planet thrown upon the of the 11th or 12th magnitude, and belong to
rings. the exterior portion of the ring. No. 153, de 4. That the cloud-forms seen near the outer tected by Palisa, November 2, 1875, and which border of the ring C attain different heights, and was named Hilda by Dr. Oppolzer, has a much change their relative position, either by the rotation longer period than any other yet discovered. indicated by the rapid changes in the indentation of Its mean daily motion, according to Dr.
the shadow of the planet. Schmidt, is 452", which corresponds to a 5. That the inner portion of the dusky ring disperiod of 2,865 days, or seven years and ten appears in the light of the planet at that part which months. This is more than double the period is projected upon its disk. of many asteroids in the inner portion of the than in the more central parts, the light diminishing
6. That the planet is less luminous near its limb The mean distance—that of the earth gradually in approaching the border. being unity-is 3.95. The eccentricity of the 7. That the dusky ring is not transparent throughorbit being 0.1487, and the inclination 7° 45', out, contrary to all the observations made hitherto; the least distance between Jupiter and Hilda and that it grows more dense as it recedes îrom the will be less than one-fifth of Hilda's greatest the limb of the planet ceases entirely to be seen
planet, so that, at about the middle of its width, distance from the sun. At times, therefore, through it. the motion of the asteroid must be greatly dis 8. And, finally, that the matter composing the tirbed.
dusky ring is agglomerated here and there into small The elements of several recently-discovered masses, which almost totally prevent the light of
the planet from reaching the eye of the observer. members of the group have not yet been computed. The mean distance, eccentricity, in Comets.—It is remarkable that no nero telclination, and longitude of perihelion, of those escopic comet has been discovered since 1874. detected since October 1, 1875, are given, so This is the longest barren interval in the last far as known, in the following table:
forty years. Some interesting researches, how
ever, have been published during the past year, on the four nights were 18, 6, 9, 7. There was, in regard to the periodic cornets of D'Arrest therefore, a regular decrease from the 10th, and De Vico, both of which will return to the apparent exception on the 11th being due perihelion in 1877. The observations on the to the haze. Making all allowance for unfavorformer, together with the perturbations pro- able circumstances, Prof. Herschel thinks the duced by Venus, the earth, Mars, Jupiter, and shower of 1876 indicates a minimum. Saturn, have been discussed by M. Leveau, of On the evening of October 18, 1876, from the Paris Observatory. Leverrier's Bulletin about half-past seven to nine o'clock, meteInternational, of March 18, 1876, gives the ors were seen in greater numbers than usual elements obtained by M. Leveau for the next at Bloomington, Ind. The maximum numreturn of the comet, as follows:
ber for one observer was eleven per hour. Time of perihelion passage...
They all diverged from the vicinity of a point
..May 10, 1877. Longitude of perihelion...
between Taurus and Auriga. Most of the Longitude of ascending node.
meteors were small, though two were seen of Inclination.. Fecentricity.
extraordinary magnitude. At Newburyport, Perihelion distance...
Mass., on the same night, at two o'clock A. M., Semi-axis major.
a bolide was observed to start from the same Sidereal period.
part of the heavens. De Vico's comet of short period has not
It was half the apparent size of the moon, which been seen since 1844. This body is regarded it rivaled in brightness, the smallest objects being by Leverrier as identical with the comet dis- visible in the intense white light of about two covered by Lahire in 1678. It is situated most seconds' duration. It left a train 10° long and favorably for observation when the perihelion visible over a quarter of an hour. While the train
one-fourth of a degree wide, which remained passage occurs about September 4th, and it is
was being observed a large number of smaller remarkable that those of 1678 and 1844 took meteors passed, as often as ono a minute, over the place within a few days of the most favorable same field, one or two of them leaving a slight date. A possible reason for the non-recovery
train. of the comet at any recent return was given in The meteors of November 14th move in the Nature for July 27, 1876. The orbit of De orbit of Tempel's comet (1866), and are the Vico's comet approaches very near to the orbit débris resulting from its disintegration. The of Mars at two points falling near 42° and 287° comet, together with the principal swarm of heliocentric longitude. At the former point meteors which immediately follow it, is now the distance between the two orbits is about approaching its aphelion near the orbit of 2,000,000 miles, and at the latter somewhat Uranus. As the existence, however, of more less than 1,000,000; "and it is to be borne in than one cluster in the same orbit has been mind that these distances, small as they are, clearly indicated, a yearly watch will be nemay have been diminished very sensibly by the cessary, while passing the node, in order to effect of accumulated perturbation since 1855, discover the law of meteoric distribution. “On beyond which we have no calculation of the the morning of November 14th” (according effects of planetary attraction. If the mean to Prof. Newton), “ between twelve and one diurnal motion in 1855 were as large as 652.05", o'clock, the sky at New Haven was partly a value considerably within Brünnow's sug- clear. Out of about twelve meteors seen, three gested limits, the comet might have come into might be called conformable to the radiant in extremely close proximity to Mars at the end Leo. Shortly after one o'clock the sky became of August, 1866, in about 42.3° heliocentric wholly overcast." longitude."
Aërolites and Meteoric Fire-balls.--In the Meteors.-Between ten and twelve o'clock American Journal of Science for June, 1876, on the night of April 18, 1876, meteors were Prof. J. Lawrence Smith, of Louisville, Ky., seen in unusual numbers near Ellettsville, describes a fire-ball seen by himself and Ind. A large majority of those whose tracks many other observers to pass Louisville on were well observed were conformable to the evening of January 31st, at half-past the radiant in Lyra. Several were remark- five o'clock. The meteor was first seen about ably brilliant, apparently equal to stars of the 60° above the horizon: its direction was from first or second magnitude. The meteors of northwest to southeast; duration of flight, this epoch are supposed to be derived from two or three seconds; apparent size, one-sixthe first comet of 1861, and to move in the teenth that of the moon's disk. The bolid same orbit.
exploded about 10° above the horizon, when Watch was kept for meteors at York, Eng- all the fragments disappeared, except tho land, on the nights of August 10th, 11th, 12th, largest, which continued its course very nearly and 14th. Several nights preceding the 10th to the horizon. were cloudy, and the 11th was very hazy. A fall of aërolites took place near Ställdalen, The brightness of the moonlight also inter- in Sweden, June 28, 1876, between the hours fered with the observations, except on the of eleven and twelve A. M. The fall of the 14th, which may be regarded as the close of stones was accompanied by a brilliant light, the August epoch. The hourly numbers radi- though the day was cloudless. Two or three ating from Perseus, seen by a single observer, loud detonations were heard, after which the
meteorites were seen to fall by eight or ten The fragments thrown off by the explosion persons. Twelve fragments were found, the were more retarded than the principal mass largest of which weighed four and a half by the resistance of the atmosphere, so that, pounds.
in the last part of the course, the appearance On the 25th of June, between nine and ten was that of an elongated cluster about 30 in o'clock A. M., a small meteorite fell in Kansas breadth and 20° in length. The height of City, Mo.
the meteor when first seen was probably 70 or A large fire-ball, moving in a westerly direc- 75 miles; length of the visible track, 1,000 tion, passed over the States of Michigan and miles; time of flight, two minutes; velocity Wisconsin, on Saturday evening, July 8th, with reference to the earth's surface, 8 miles about fifteen minutes before nine o'clock per second ; true orbital velocity, between 22 (Chicago time). It was seen by Mr. E. L. and 25 miles per second. The interval between Linsley, at Stratford, Conn.; Mr. Benjamin the disappearance of the meteor and the vioVail, at Henryville, Clarke County, Ind. ; Mr. lent detonation as observed at Bloomington, William L. Taylor, at Wolcottville, La Grange Ind., was fifteen minutes, indicating a distance County, Ind. ; Rev. Robert Beer, at Valpa- of about 180 miles. A fragment of the meraiso, Ind., and by niany others in various teoric mass, weighing about a pound, was found parts of the Western and Northwestern States. three miles northwest of Rochester, Fulton From the observations of the persons named, County, Ind., on the following morning, Dewith those of others who witnessed the phe- cember 22d. nomenon, it has been found that the course of Star Systems.–Polaris has long been known the meteor was a few degrees north of west; as a double star, its companion being of the that its height when first observed was cer ninth magnitude, and at a distance of eighteen tainly over 100 miles; that it passed vertically seconds from the larger component. In 1869, over the counties of Branch, St. Joseph, Cass, M. de Boë, at Antwerp, detected two other and Berrien, Mich. ; that it did not reach the companions, much nearer and fainter than that earth's surface, but passed out of the atmos- previously known. The observer sought, subphere in its cometary orbit about the sun; and sequently, to confirm his discovery, but his efthat its nearest approach to the earth could forts, until recently, were without success. In not have been less than 70 miles.
1876, using a six-inch equatorial, he rediscovThe meteor was apparently one of great ered the two new stars, and the observation magnitude, as its brilliancy was compared by has been lately confirmed by that of Baron von observers to “the glare of a calcium-light.” Eithorn. The light of the new members of The body left a luminous track in the atmos- the system is probably variable. phere, which continued visible at least thirty The Binary Star Omega Leonis. — In the minutes.
Transactions” of the Royal Irish Academy, On Saturday morning, December 16th, at vol. xxvi., Dr. Doberck, of Markree Observa12h. 45m., an immense ball of fire was seen from tory, Ireland, has given the details of his elabSan Francisco, Cal. When first observed it orate determination of the elements of this was descending rapidly, and, a few moments binary system. The period is 111 years-conafterward, it fell into the sea at apparently no siderably greater than that of Uranus; the ecgreat distance from the shore. The fall was centricity, 0.536. followed by a loud explosion.
Gamma Coronæ Australis.-Prof. SchiapaOn Thursday evening, December 21st, at relli has recently measured this binary star with 89. 45", Cincinnati time, a meteor of extraor- the eight-inch Merz equatorial of the Observadinary magnitude passed over the States of tory of Brera, Milan, and, by comparing his Kansas, Missouri, Illinois, Indiana, Ohio, and own observations with those of Poweil, Sir Pennsylvania. Its course was 17° or 18° north John Herschel, and Jacob, has calculated its of east, and it passed almost vertically over orbit. The periastron passage will take place Fort Riley, Kan.; Weston, Mo.; Peoria, Ill. ; in 1882; the orbital eccentricity is 0.6989, and Rochester, Ind. ; Toledo, Ohio, and Erie, Pa., the period of revolution 55.582 years—somesomewhat south, however, of the place last what greater than that of Sirius. named. At Bloomington, Ind., the meteor Eta Cassiopeia. During the past year, Dr. was first seen at a point about 10° south of Doberck has rediscussed the observations of west, and less than 5° above the horizon. It this star and obtained new elements differing appeared as a single globe of light, surpass- considerably from those previously computed. inz the moon in magnitude and brightness. The periastron passage will occur in the spring When northwest of Bloomington, Ind., or soon of 1909; the eccentricity is 0.5763; the period, after it had passed the zenith of Peoria, Ill., 222.4 years; and the semi-axis major, 9.83". the body was seen to separate into numerous The parallax of Eta Cassiopeiæ, according to fragments. The apparent size, however, of Struve, is 1.4 of a second. It results from the principal mass, was not sensibly diminished. these data that the mean distance of the comThe explosion was followed by a violent deto- panion from the principal star is about 64 times nation, resembling a heavy clap of thunder. the radius of the earth's orbit, and the mass of The height of the meteor when the explosion the system 5.25 times that of the sun. The occurred was estimated at from 45 to 48 miles. distance and apparent magnitude of this binary
system are very nearly identical with those of the trapezium in Orion. The instrument used 70 Ophiuchi, while the mass of the latter is less was the Foucault telescope of 31 inches aperthan that of the former in the ratio of three ture, then recently mounted. Especial attento five.
tion was given to those stars which M. 0. Sirius.—From a discussion of the observa- Struve had designated as variable, and not tions of the companion of Sirius, Dr. Auwers only were the suspicions of the Pulkowa obhas found the period of revolution to be 49 server for the inost part confirmed, but in the years and 146 days; the semi-axis of the or case of several other stars in which he had bit, 37 times the distance of the earth from the detected no change variations of magnitude sun; and the eccentricity, 0.6148—somewhat were clearly indicated. The existence of so greater than that of Faye's comet. The mass many variable stars in this remarkable nebula of the companion is half that of the principal will be regarded by astronomers as a fact of star; or, more exactly, the mass of Sirius is no ordinary interest and significance. 13.76, and that of the telescopic star 6.71, the The Pleiades.—The report of the Council mass of the sun being unity. As the light of of the Royal Astronomical Society to the Sirius, according to Sir John Herschel, is 324 fifty-sixth annual meeting (1876) contains times that of an average star of the sixth mag- the following statements in regard to the nitude, and as the satellite discovered by Pleiades group, several members of which are Clarke is of the ninth or tenth magnitude, the found to be variable : light of the latter must be much less than onethousandth part of that received from the prin- series of measurements of this interesting group of
M. Wolf, of the Paris Observatory, has made a cipal star. The facts seem to indicate å re stars, including all visible through an object-glass markable difference between the physical con of 0.31 millimetre aperture. The exact positions of stitution of Sirius and its satellite.
the 53 stars observed by. Bessel, referred to Eta Procyon. It was stated, in our volume for distance, are given in a table containing the meas
Tauri by differences of right ascension and polar 1874, that M. Otto Struve had discovered a
surements of M. Wolf, compared with those of small companion of Procyon, by which it was Bessel reduced to January 1, 1874. The relative believed the anomalous motion of that star magnitudes of these 53 principal stars have been might be satisfactorily explained. Strangely any possible variation of brightness since Bessels
determined with very great care, in order to detect enough, however, the most diligent search for observations. M. Wolf has been able to detect no this new star with the twenty-six-inch re less than 499 stars around Eta Tauri, contained fractor of the Washington Observatory has within a rectangle of 135 minutes of arc in length been hitherto unsuccessful, although three and
90 minutes breadth. These vary from the third other companions have been distinctly recog. tudes have been compared with those in the cata
to the fourteenth magnitude. The observed magninized by Profs. Newcomb and Holden ; their logues of Jeauret, Lalande, Piazzi, Bessel, and distances from Procyon being 6", 9", and 10", Argelander; from which M. Wolf concludes that respectively. The difference of atmospheric among the eight principal stars of the group, circumstances could scarcely explain the con
Merope and Atlas are decidedly variable, and Maia
appears also to have increased in magnitude since tradictory character of the observations at
the observations of Piazzi and Bessel. The five Polkowa and Washington. We must conclude, others show no evidence of variability, but some of therefore, that the observations of Struve were the smaller stars have certainly changed their relasomehow erroneous, or that the light of the tive brightness since the former observations. new star is variable.
He concludes, from a comparison of the differ
ences between his and Bessel's measurements of Cincinnati Catalogue of New Double Stars. the 53 principal stars, that the Pleiades form a group - The search for new double stars has been whose members are physically connected one with recently prosecuted with eminent success at the other; and, moreover, there appears to exist in the Cincinnati Observatory. As a first result the group a relative displacement of the stars, which of these labors, the director, Mr. Ormond direction to the diurnal motion, slightly diminish
carries the greater number of them in a contrary Stone, has distributed a catalogue of fifty, all ing their polar distance. M. Wolf hopes that his two included in the zone between 8° and 40° south years' observations may serve as a certain basis, at declination. They vary in distance between à future period, for the determination of the proper 0.8" and 8”. The estimated magnitudes of motion of the separate components forming the
group. the components are given, together with their distances asunder, and their angles of position. Spectroscopic Observations.—Sir George B.
Variable Stars.—Dr. Gonid, Director of the Airy, the astronomer royal, has recently pubCordova Observatory, has found the period of lished the results of spectroscopic observaa variable star in Mosca to be less than that of tions made at Greenwich for determining the any other variable hitherto determined. This motions of stars in the line of sight. The star, at minimum, is entirely beyond the reach velocity of approach or recession of the stars of unassisted vision even in the sky of Cor- observed is found by the displacements of the dova, though at maximum it is distinctly visi- lines of known elements in their spectra; the ble. The period of variation is about thirty estimated rates of motion being corrected for hours.
the earth's velocity resolved in the direction In February, 1876, M. Tisserand, Director of the star. The rate of recession assigned to of the Observatory of Toulouse, undertook a Sirius by these observations is 27 miles per series of observations on the small stars near second, or about 852,000,000 miles per annum
VOL. XVI.-4 A
2+ 27 33 39 50
–a velocity considerably greater than that of with. Merope, but extending slightly toward the the earth in its orbit. At this rate of motion east; the other, more luminous, was about seven the star will describe a distance equal to that the diaineter being about one second. From the
seconds of arc from the star, on the same parallel, which now separates it from the solar system month of November, 1874, to the end of February, in less than 140,000 years. The velocities 1875, the nebula was invisible, although it was with which certain other stars are receding looked for on many occasions when the sky was from the solar system are as follows:
very favorable for the purpose. M. Wolf, therefore,
considers that this nebula is certainly variable, with Beta Ursæ Majoris.... 15 miles per second. a‘moderately short period. Castor....
Knobel's Reference Catalogue of AstronomiRigel.
cal Papers and Researches.-The thirty-sixth Regulus Procyon..
volume of the “Monthly Notices ” of the Spica..
Royal Astronomical Society contains, in its
supplementary number, an elaborate and exThe following, on the other hand, are ap- haustive catalogue of the literature of sidereal proaching the sun:
astronomy. This catalogue, prepared by E. Alpha Pegasi. 22 miles per second. B. Knobel, Esq., consists of a list of references Arcturus
to all books, papers, and notes, relating to the Vega.. Alpha Andromeda... 39
following subjects : Alpha Ursæ Majoris... 40
1. Double Stars, including the Mathematical Gamma Leonis.......
Investigation of the Orbits of Binary Systems.
2. Variable Stars. It will be noticed that Alpha and Beta of
3. Red Stars. the Great Bear (the two stars known as “the
4. Nebulæ and Clusters. pointers”) are moving in different directions.
5. Proper Motions of Stars. The former, which is nearer the pole, is ap 6. Parallax and Distance of Stars. proaching the sun; the latter is receding from
7. Star Spectra. it.
The list of references is derived mainly from Nebulæ.-M. Stephan, Director of the Mar
a systematic examination of the libraries of seilles Observatory, has been recently devoting the Royal Society and the Royal Astronomical special attention to the search for new nebulæ. Society, the first of which is said to be peculThe result has been the discovery of 400 of iarly rich and complete in the transactions of these bodies, all of which had escaped the scientific societies. The work was prepared, notice of former observers. The fact that the compiler informs us, “in the hope that they are generally small is favorable to the these references may be found useful to asaccurate determination of their positions—a tronomers in guiding them to the particular point of great importance for the future inves- literature giving information on the abovetigation of their proper motions.
mentioned branches of stellar astronomy, and Supposed Changes in Messier's Nebula No. 17. thereby reducing their labors in reading up - This nebula, which was discovered by Mes- the subject to a minimum.". sier nearly a century since, has lately been the
Gold Medal of the Royal Astronomical Sosubject of critical study by Prof. Edward S. ciety.—The gold medal of the Royal AstroHolden, of the Washington Observatory. It nomical Society was awarded, in 1876, to M. was the object of these researches to deter- Leverrier, Director of the Paris Observatory, mine whether the nebula has undergone any for his theories of the four great planets, sensible changes since the date of the earliest Jupiter, Saturn, Uranus, and Neptune. "Levertrustworthy descriptions. The conclusion de- rier's theoretical investigations of the motions rived from an elaborate discussion is that, of all the principal planets have now been prewhile the stars in and about the nebula have sented to the Académie des Sciences. His retained their relative positions, the part of theories of the four inner planets were comthe nebula known as the “ Horseshoe” has pleted several years since, and for these, it moved with reference to the stars, and that, will be remembered, the medal of the society therefore, we have evidence of a change going was awarded him in 1868. At the annual on in this nebula." This may be a change in meeting in February, 1876, the president, the nebula's internal structure, or it may be Prof. Adams, reviewed the labors of the dis"the bodily shifting of the whole nebula in tinguished mathematician, upon whom the space in some plane inclined to the line of highest honor of the association had been a sight."
second time conferred ; explained the grounds Variable Nebula in the Pleiades.-Of this
on which the council had based their decision; interesting object the Monthly Notices” of and, in concluding, expressed to M. Leverrier the Royal Astronomical Society for February, the deep interest with which astronomers had 1876, says:
followed him in his unwearied researches, and The most remarkable object of the group is the the admiration which they had felt " for the nebula around Merope. Discovered by M. Tempel skill and perseverance by which he had sucin 1859, it has also been seen by Profs. D'Arrest and ceeded in binding all the principal planets of Schmidt, who were of opinion that the nebulosity must be variable. On March 7, 1874, it consisted of our system, from Mercury to Neptune, in the two portions, one of which was nearly concentric chains of his analysis."