356 



KNOWLEDGE. 



September, 1913. 



Jupiter is now rather low in the West. Polar semi- 

 diameter, 17i" in mid-October. 



Table 63. 



Configuration at 6 h 30 m m for an inverting telescope. 



Satellite phenomena visible at Greenwich, l d 8 h 22 ra I. Tr. 

 I., 9 h 41 m I. Sh. I.; 2 d 5 h 37 m I. Oc. D., 8 h 4 m 36 s II. Ec. 

 R. ; 9 h 12 m 41 s I. Ec. R. ; 3 d 6" 29 m I. Sh. E. ; 7 d 5 h 57 m 



III. Tr. I., 9 h 16 m III.Tr. E. ; 9 d 7 h 33 m I. Oc. D. ; 10 d 6 h 5 m 



I. Sh. I., 7 h 5 m I. Tr. E., 8 h 24 m I. Sh. E. ; ll d 5 h 25 m II. Sh. 

 E., 5 h 36 m 30 s I. Ec. R. ; 13 d 7 h 44 m IV. Sh. I.; 16 d 7 h 54 m 



II. Oc. D. ; 17 J 6 b 44 m I. Tr. I., 8 h l m I. Sh. I.; 18 d 5 h 9 m 

 II. Sh. I., 5 h 25 m 43 B III. Ec. D., 5 h 29 m II.Tr.E., 7 h 31 m 33 s 

 I. Ec. R., 8 h 1 B II. Sh. E., 8 h 44 m 34 s III. Ec. R. ; 21 d 5 h 24 m 



IV. Oc. D., 8 h 43 m IV. Oc. R. ; 5 h 19 m II. Tr. I., 5* 56 m I. 

 Oc. D., 7 h 44™ II. Sh. I., 7 h 47 m III. Oc. R., 8 h 10 m II. Tr. 

 E. ; 26 d 5" 31 m I. Tr. E., 6 h 45 m I. Sh. E. ; 27 d 5 h 18 m 31 s II. 

 Ec. R. ; 30 d 5 h 44 m IV. Sh. E. All these are in the evening 

 hours, the planet setting before midnight. Attention is called 

 to the double eclipses of 2 d , 18 d , 25 d . On the 25th there is 

 only one satellite visible outside the disc. Satellites 1, 2, 4, 

 are all near together on 30th. 



Saturn is a morning star, in Taurus, in a good position for 

 observation. Polar semi-diameter 9". P. is — 4°-9; ring 



major axis 46", minor 20£". The ring is very widely open. 

 It is of interest to examine the exact amount of overlap 

 beyond the planet's pole. 



East Elongations of Tethys (every fourth given), 2 d h -6m, 

 9 d l"-8e, 17 d 3 h -0w, 24 d 4 h -2e, Nov. l d 5 h -4m; Dione (every 

 third given), l d 2 b -3c,9 d 7 h -4e, 18 d h -4m ; 26 d 5 h -4m; Rhea 

 (every second given), 3 d 7 h - 9c, 12 d 8 h -7c, 21 d 9 b -5e, 00 d 10 h -2e. 

 For Titan and Iapetus E.W. mean East and West Elonga- 

 tions; I. Inferior (North) Conjunctions, S. Superior (South) 

 ones. Titan, l d 7 h -4e I., 5 d 3 h -8eW. ; 9 J 3"-2e S., 13 d 6 h -le 

 E., 17 d 5 h -9 d e I., 21" 2 h -3e W., 25 d l h -5e S., 29 d 4 h -le E. ; 

 Iapetus, 20 d 7 h -4ra I. 



Uranus is an evening star. Semi-diameter, lj". About 2° S. 

 of p Capricorni. 



Neptune is a morning star. 



Meteor Showers (from Mr. Denning's List) : — 



Double Stars and Clusters. — The tables of these given 

 last year are again available, and readers are referred to the 

 corresponding month of last year. 



Variable Stars. — Tables of these will be given each 

 month ; the range of R.A. will be made four hours, of which two 

 hours will overlap with the following one. Thus the present 

 list includes R.A. 22 h to 2 h , next month h to 4 h , and so on. 



Table 64. Non-Algol Stars. 



(3 Lyrae minima Oct. 13 d 9 h e, 26 d 7 h e, Period 12 21 -8 h . 

 Algol minima Oct. l d 4 h 21™e, 10 d 6M8 m m, 13 d 3 h 37 m m, 16 d h 26 m m, 18* 9 h 15 m e, 21 d 6 h 3 m e, Period 2 d 20 -8 h . 



