ASTRONOMICAL PHENOMENA AND PROGRESS. 



Prof. Young and Mr. McNeill showed unmis- 

 takably the presence of water-vapor in the at- 

 mosphere of Venus. " Between the first and 

 second contacts the atmosphere of the planet 

 was conspicuous as a delicate halo around its 

 disk." 



The transit was observed at Vassar College, 

 Poughkeepsie, N. Y., by Prof. Maria Mitchell ; 

 at Harvard College Observatory, by Prof. Pick- 

 ering and others ; at Dearborn Observatory, 

 Chicago, by Professors G. W. Hough and S. W. 

 Burnham; at Allegheny Observatory, Pa., 

 by Prof. 8. P. Langley ; at Tarrytown, N. Y., 

 by Mr. Charles H. Rockwell ; at Columbus, O., 

 by Prof. R. W. McFarland and Mr. F. H. El- 

 dredge ; at Phelps, N. Y., by Mr. W. R. Brooks ; 

 at Nashville, Tenn., by Prof. E. E. Barnard ; at 

 New Windsor, 111., by Prof. E. L. Larkin ; and 

 by many others in various parts of the country. 

 The observations of foreign astronomers were 

 also generally successful. "How long it will 

 be before the observations, especially the pho- 

 tograph and heliometer measures, are fully re- 

 duced and published, it is impossible to say. 

 It must be years at least. After this is done, 

 it will be extremely probable that some high 

 authority, perhaps an international commis- 

 sion, should collect and discuss all the various 

 observations, both of this transit and that of 

 1874, and, from the enormous mass of material 

 thus obtained, deduce the best final result which 

 it can furnish a result which can not fail to be 

 of the highest value in settling the dimensions 

 of our universe." * 



Mr. A. Stanley Williams, who observed the 

 transit at Brighton, Eng., while examining the 

 border of light around Venus, noticed this 

 fringe to be very conspicuous on the southern 

 portion of the planet's limb, but very faint and 

 narrow elsewhere. During the transit, how- 

 ever, some change was manifest in the relative 

 brightness at different parts of the ring. The 

 phenomenon was ascribed by Mr. Williams to 

 the presence of clouds on the limb of Venus. 



The Moon. In " The Observatory " for March 

 and April, 1883, Mr. A. Stanley Williams, of 

 West Brighton, Eng., gives an interesting ac- 

 count of his observations on the lunar crater 

 Plato during the past five years. The condi- 

 tion of our satellite has long been regarded as 

 dead and changeless ; but the observations of 

 Mr. Williams, in connection with a most care- 

 ful examination of the floor of Plato by several 

 astronomers from 1869 to 1871, reveal the fact 

 of undoubted physical changes within the past 

 twelve years. The evidence of variation does 

 not rest on the testimony of a single observer. 

 Observations of Plato were simultaneously con- 

 ducted by the Rev. J. B. Allison, of Chester- 

 field; W. F. Denning, of Bristol; T. P. Gray, 

 of Bedford ; and H. Pratt, of Brighton. Some 

 of the changes discovered by a comparison of 

 the late observations with those of 1869-'71 

 are as follow : 



1. Of the thirty-seven spots observed and 

 * " Sidereal Messenger, 11 February, 1883. 



mapped about 1870, six have entirely disap- 

 peared. Seven new ones have been found, 

 however, during the recent observations. 



2. A very large increase in visibility is found 

 in the spots numbered 12 and 13 on the chart 

 of the floor of Plato. The latter also exhibits 

 some remarkable changes in form. 



3. No. 16 has to a considerable extent de- 

 creased in brightness. 



4. Several streaks in the floor of the crater 

 have sensibly increased in breadth ; three new 

 streaks have appeared within the past ten 

 years, and several that were distinctly visible 

 about 1870 can not now be found. 



5. Very obvious changes in the state of the 

 floor of the crater have taken place since the 

 observations of 1869-'71. 



Diameter of the Moon. Prof . H. M. Paul, of 

 the United States Navy, has lately redeter- 

 mined the semi-diameter of the moon from two 

 occultations of the Pleiades, observed on July 

 6, 1877, and September 6, 1879. His value of 

 the mean apparent semi-diameter is 15' 31*78" ; 

 corresponding to a diameter of 2158*3 miles. 



Minor Planets. The 232d minor planet was 

 detected on the 21st of January, 1883, by Herr 

 Palisa, of the Vienna Observatory. It is of 

 the twelfth magnitude, and is the thirty-ninth 

 discovered by this observer. The right to 

 select a name was delegated to Dr. Engel- 

 hardt, of Dresden, who called it Russia. Its 

 elements, computed by Dr. Herz, from Vienna 

 observations of January 31st, Rome, March 

 8th, and Dresden, April 13th, are as follow : 



Epoch, April 15- 5, Berlin mean time. 



Longitude of perihelion 200 24' 87' 



Longitude of ascending node 152 80 28 



Inclination 6 8 34 



Mean daily motion 870-2296" 



Period 1489 26 days. 



Mean distance 2-5522 



Eccentricity '. 1 754 



The mean distance falls in the cluster imme- 

 diately exterior to the well-known hiatus where 

 the period of an asteroid would be one third 

 that of Jupiter. 



Another asteroid was discovered at Mar- 

 seilles, on the llth of May, by M. Borelly. Its 

 light is about equal to that of a star of the 

 eleventh magnitude. The third minor planet 

 of the year was detected, August 12th, by Dr. 

 Peters, of Clinton, N. Y. This is the 234th 

 of the group, and the 42d discovered by him. 

 It is of the ninth magnitude, and its approxi- 

 mate elements are as follows : 



Epoch, 1883, August 30- 5, Berlin mean time. - 



Longitude of perihelion 332 6' 35 5" 



Longitude of ascending node 144 6 44 



Inclination 15 81 19 



Eccentricity 0'2436 



Mean daily motion 956'674" 



Period 1354-7 days.' 



Mean distance... 



Owing to the great eccentricity of this 

 planet's orbit, its least distance from the sun 

 is only T812. Its remarkable brightness when 

 discovered was due to the fact that it was 

 nearly in opposition, as well as near the sun, at 

 the time of its detection. The 235th minor 



