M 



AflTKoNoMV. PIUMiKKSS OK. IN 189ft. 



d that, undoubi. 

 of Man we* bMtrUy laden 

 .for certain baud, wrr* MI which corre- 

 wfch UM band* of water vapor loud on 

 lif h in thr M~ :*ing and setting 



8w. Btaooami^of ilwspectnunof Mar* 

 S *Sft * ti Moon, tb. latter being at a 

 lower etottad* Ihan tbr form. igfint 



proved the* UMM band* wr* not due to the in- 



Seeingt! 



id thai ihr trllunc Und* f t h, Karth's atraos- 

 plHfeoUbaso 01 > at a very 



CwafetaH * the tflftilttl indication <>f 1 h- 

 of water vaporte the spectrum of Man 



in hisatmos- 



Uarr satrlllt* t Mar*. -Observations of 

 thfe sBtelUt* (Phoboa), made by Prof. W. W. 

 najjl'Tin -* UM Uck Observatory. between Oct. 

 aad Mov. 14. 1*N. show that its eastern 

 etoayetion oorors at a considerably greater dis- 

 laoc* from the planet than does the western 

 NaMllun lW. HalKs studies at the time of 

 jJMJTuiJ ii f these sateUitet of Mars plainly 

 vfaMd that the western elongation of Phobos 

 was than noticeably greater than iU eastern. 

 This variation can be accounted for only by the 

 involution of the orbit itoelf. 



Polar Refloat of Mare. Bet ween the years 

 1181 and ITOS Sir William Herchel noticed 

 be polar snow caps of Mars waxed and 

 with the Martial seasons, increasing as the 

 advanced, and dim i ni-h i MJ; with the prog- 

 of summer, but. until October, 1894, they 



been known to entirely disappear. 



JBr William found that while the north rap had 

 to center exactly at the north pole of the planet, 

 that of the southern cap was 6 or 8 degrees 

 Ito south pole: hence, when the southern 



nd. 7 ' Plot 



: ; .;!! 

 was seen very irregular in 



r. all melted away and dis- 



appeared. totrampt*U.oftheLickObserv- 

 - bo has been a student of Mars, says that 

 oa July It, INK*, an intensely white spot was 

 mm partly detached from UM main cap. but pro- 

 >*% brand i U Whan, two yean later, on 

 JaJyft I W. it wa. observed the'aonthern s\ira- 

 arof Man ww more advanced, the cap, grown 

 Ml the white spot behind, detach- 



latartlianat 1 .... -r aJUtode*. 



nr of l.rn.-Prof, Campbell dotibU 

 of an atmosphere on Man, but the 

 ftlie.petro.Mpeiii the hands of 



to him regardmg this particular. * PP > 



J pltw. For the ascertainment of his she, 

 hb rotational period, UM nature and cause of h& 

 belts and white and dark spota, the ream of the 



dark transits of some of his satellites, and of 



their sometimes " N|liarc-.xli. -llldercd " I 



ance and, again, their duplex M , mm-, like a 

 double tftar, much -n,d\ has been evoked ; but 

 while some of the mysteries of the giant planet 

 have been solved, yet many secret- am 

 locked in this massive world. 



1 1. the account of his measures of the diameter 

 of .lupitr. hi. itarnard calls marked attention to 

 the discrepancy bet ween those made b\ the aid of 

 the fllar micrometer and those of the help 

 the former Divine a diameter about 1' greater 

 than the lat ll he attributes to the defec- 



tive images formed by the divided halves ,f the 

 object glass, and hence he concludes that for 

 planetary diametrical measurements the hdi- 

 ometer is a defective instrument The mean of 

 all his measures gives (at distance 5-Jo. the 

 Karth's distance beinj; taken a- unity) ! 

 56 miles as the equatorial diameter, and 

 75 miles as the polar diameter, the polar com- 

 pression being -r^ir. 



Mass of Jupiter. "Astronomic h. Na -h- 

 richten," No. 8249, has an article bv 

 Simon Newcomb which embodies much valu- 

 able information on this subj. :. !! says: 

 "The following table shows the values and the 

 relative weights to which 1 have judp.. 

 one entitled. I do not deem it neressary at the 

 present time to give in all detail the oonaidera- 

 t ions which led to the adoption of these weights. 

 I may remark, however, that Von Haerdtl's ex- 

 cellent result from the perturbations of \\ 'in- 

 necke's comet, which has by far the -mallet 

 probable error of any determination yet made, 

 has not been assigned a corresponding weight 

 because of a distrust on my part whether 

 vat ions oi> a comet can be considered a- hav- 

 ing always been made in the center of L 

 of a well-defined mas- moving as if its center 

 were a material point subject to the gravitation 

 of the Sun and planets. This distrust seems to 

 me to be amply justified by our general experi- 

 ence of the failure of comets to move in exact 

 accordance with their ephemerides. The mass 

 of Jupiter, from all observations on the satel- 

 lites, 



=-. 1047-82. weight = 1 



Action of Fmy' comet = 1047-79, u =1. 



MUroid Themis = 1047 54, " =5. 



on Saturn =1047-88, " = T. 



a*t*rod PolyhrmoU=104784, " =20. 



" - Wlnnecke'* comet =1047-17, - =10. 



Wdfhted OMMI = 1047-85. 



.luj.it. i -. Ihird satellite. As a test of the 

 correctness of Prof . W. II. Pickering' 

 the elongation of the li>k of the third satellite 

 of Jupiter, hr. Marnard. witli the 36-inch t. 1- 

 scope of the l.jek observatory, has subjected 



'-ii to a Hirid examination, wit h 

 Milt that, with all in.wers up to 1,000 diai 

 the satellite remained perfectly round, even 

 when the eye was put into different j 

 angles. The u-ual markings were seen, but no 

 distortion of the disk was observed at any time, 

 with any power, and under the best conditions 

 of awing. 



k Transit of Satellite III. On Feb. 8, 

 1896, M observed at Greenwich, this satellite 

 Passed on to the disk of the planet at 7 1 " 3. At 

 7* 80- it was invisible. At 8^, and until about 

 a half hour before egress, it was seen as a dark. 



