THE FACE OF THE SKY FOR OCTOBER. 



By W. SH.VCKLETON, F.R.A.S., A.K.C.S. 



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The Sun. — On the 1st the Sun rises at 6.1 and sets at 

 5.39; on the 31st he rises at 6.52 and sets at 4.35. Sunspots 

 and faculae may usually be seen on the disc, though of late the 

 spots have been rather small. The granular structure of the 

 surface can be particularly well seen on foggy mornings, as 

 the atmosphere is quiet and the image steady. The positions 

 of the Sun's axis, centre of the disc, andheliograpliic Icmgitnde 

 of the centre are given in the following table : — 



The Moon : — 



OCCULTATIONS. — The following table gives particulars of 

 the principal occultations visible from Greenwich. 



The second magnitude star o Scorpii is occulted just before 

 Sunset, but the phenomenon can be observed with telescopes 

 of moderate aperture since the star is bright. 



The Pl.\nets.— Mercury (Oct. Lst, R.A. ll'' 49"; Dec. 

 N. 0^ 5'. Xov. 1st. R.A. 13" 58"'; Dec. S. 10° 50') is a 

 morning star in Virgo, rising on the 15th about 4.30 a.m. or 

 1" 40"" before the Sun. The planet is at greatest westerly 

 elongation of 18° 3' from the Sim on the 11th. The elongation 

 is moderately favourable for observation except that the 

 planet is only visible in the early morning. 



Venus (Oct. 1st, R.A. ll" 37'"; Dec. N. 4° 2'. Nov. 1st, 

 R.A. 14 1'" ; Dec. S. 11" 5') is a morning star in Virgo, rising 



at 5.20 a.m. on the 15th. The planet is practically invisible as 

 she will shortly be in superior conjunction with the Sim. The 

 planet is in conjunction with Mercury on the 3rd. 



Mars (Oct. 1st, R.A. 12" 24'" ; Dec. S. 1' 43' ; Nov. 1st. R.A. 

 1 3" 40"" ; Dec. S. 9° 44') is out of range for observation as he 

 was in conjunction with the Sun on the 27th of last month. 



Jupiter (Oct. 1st. R.A. 13" 20"' ; Dec. S. 7" 14'. Nov. 1st, 

 13" 45""; Dec. S. 9° 42'l is inobser\able being in conjunction 

 with the Sun on the 19th. 



Saturn (Oct. 1st, R.A. 2" 15'"; Dec. N. 10^ 39'. Nov. 1st. 

 R.A. 2" 6""; Dec. N. 9° 50') attains a greater altitude than he 

 has done for many years and is very favourably placed for 

 observation, since he is in opposition to the Sun on the 27th, 

 and visible throughout the whole night. On the 23rd he is due 

 South at midnight. The planet forms a conspicuous object 

 in the sky looking S.E., being situated about 13° South of 

 « Arietis, where he may be observed shining as a bright star 

 free from scintillation, but with a peculiar lustre which has 

 given it the name of the leaden planet. The telescope view of 

 the planet is superb, and even when other objects are difficult 

 to define Saturn e.xhibits crisp detail, well repaying observation. 

 The rin,g is visible in quite small telescopes, such as ordinary 

 good deer stalkers, with a high power eye-piece, and in a good 

 three-inch telescope the ring is visible with a power of about 50, 

 and the belts on the planet's surface with a power of about 

 80 ; using higher powers the principal division in the ring may 

 be seen. The diameters of the outer major and minor axes of 

 the ring system are respectively 47" and 14", so that the ring 

 appears well open, being inclined to our line of vision at an 

 angle of 17°, the Southern surface being visible. The planet 

 has eight satellites: of these Titan (magnitude 8'5) can be 

 observed with a good objective of two inches aperture, lapetus 

 (magnitude 9-12) may be seen at westerly elongation (Oct. 1 5th) 

 with a telescope of three inches aperture, which is also 

 sufficient to show Rhea (magnitude 9'5) and Tethys (magnitude 

 10), whilst Dione (magnitude 10'5) requires an aperture of four 

 inches. 



The three other satellites require larger telescopes since 

 their magnitude is less than 12. 



Ceres (Oct. 1st. R.A. l" 29"°; Dec S. 6° 31'. Oct. 31st R.A. 

 1" 4"° ; Dec. S. 7° 53') is in opposition to the Sun on the 9th ; 

 the asteroid then appears at its brighest, the magnitude being 

 7'5, and is thus visible in very small telescopes. The minor 

 planet is situated about 1° N. of Ceti. Ceres is probably 

 the largest of the minor planets but its reflective power is less 

 than Vesta, hence it is somewhat fainter. 



Uranus (Oct. 15th. R.A. 19" 33"; Dec. S. 22° 15') remains in 

 Sagittarius but is rather low down and sets about 10 p.m. near 

 the middle of the month. The planet is situated in a part of 

 the sky devoid of good reference stars, though the 4th 

 magnitude star h Sagittarii is about 2° to the South. The 

 planet is in quadrature on the 15th. 



Neptune (Oct. 15th. R.A. 7" Si"'; Dec. N. 21° 6') rises 

 shortly after 10 p.m. and crosses the meridian at 6 a.m. at the 

 middle of the month. The planet is situated about four-and- 

 a-half degrees South- East of the star Geminorum, is in 

 quadrature on the 15th and stationary on the 25th. 



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