THE FACE OF THE SKY FOR JUNE. 



By A. C. D. CROMMELIN, B.A., D.Sc, F.R.A.S. 



Table 25. 



Table 26. 



P is the position angle of the North end of the body's axis 

 measured eastward from the North point of the disc. B, L 

 are the helio-(planeto-)graphical latitude and longitude of the 

 centre of the disc. In the case of Jupiter System I refers to 

 the rapidly rotating equatorial zone, System II to the tem- 

 perate zones, which rotate more slowly. To find intermediate 

 passages of the zero meridian of either system across the 

 centre of the disc, apply to Ti T 2 multiples of 9 h 50 m -5, 

 9 h 55 m *7 respectively. 



The data for the Moon and Planets in the Second Table 



are now given for Greenwich Midnight, i.e., the Midnight at 



the end of the given day. 



The letters m, e stand for morning, evening. The day is 

 taken as beginning at midnight. 



The Sun is moving Northwards till the 22nd, when it 

 reaches the Summer Solstice and commences to move 

 Southward. Its semi-diameter diminishes from 15' 48" to 

 15' 45". Sunrise changes from 3 h 51™ to 3 h 49 m ; sunset from 

 8 h 4 m to 8 h 18 m . The Sun's surface is likely to repay care- 

 ful scrutiny, owing to the recrudescence of activity. 



Mercury is an evening star, till June 27th. East Elonga- 

 tion, 23° from Sun, on May 31st. Semi-diameter increases 

 from 4" to 6". Illumination diminishes from I to Zero. 



VENUS is a morning star. Illumination over nine tenths. 

 Semi-diameter diminishes from 6" to 5}". 



The Moon.— Last quarter 4° 4 h 32™ e. New 12 a 6 h 57 m e. 

 First quarter 20 d 2 h 24 m c. Full 27° 4" 27 m m. Apogee 



ll' 1 l h tn. Perigee 26° 2" ***. 



semi-diameter 14' 43", 16' 40" 



respectively. Maximum librations 3 d 8° W., 10° 7° S., 19° 7° F... 

 24 7° N. The letters indicate the region of the Moon's 

 limb brought into view by libration. E., \V. are with 

 reference to our sky, not as they would appear to an 

 observer on the Moon (see Table 27). 



Mars is still badly placed, but may be observed as a 

 morning star. Semi-diameter 24/'. 



Jupiter is a morning star, in Pisces; in quadrature with 

 the Sun on 19th. Equatorial diameter 39", Polar 37". 

 Configurations of satellites at 2 h in. 



The following satellite phenomena are visible at 

 Greenwich, all in the morning hours: — l d l h 52 ln I. Sh. E., 

 3" 12 m I.Tr. E; 2 d 3° 24 m 111. Sh. E. ; 6 J l h 2S m 19" II. Ec. 

 D. 8" l h 22"' II. Tr. 1'.. l h 27"' 1. Sh. I., 2" 50 m I. Tr. I.; 

 9 d 2" 17™ I. tic. K„ 2° iZ m IV. Sh. I. ; 13 d 2° 52'" III. Oc. 

 R. ; 15 J 1" 10"' II. Tr. I., l h 13 ra II. Sh. F... 3" .T I. Sh. I ; 

 16" h 3i m Z5" I. Ec. D. ; 1 7 a l h 30 m I. Tr. E. ; 1S° 2° 45 m 

 IV. Oc. R. ; 20 a l h 19™ 58* III. Ec. U.; Z2* h 57™ II. Sh. I.; 

 '3" 2" 27 m 33' I. Kc. D; 24° l" 6 m I. Tr. I., 1° 27 m II. Oc. R.. 

 2 h l m I. Sh. E., 3 h 24 m I. Tr. E. : 25° h 34 ni I. Oc. R. ; 



157 



