44 



KNOWLEDGE & SCIENTIFIC NEWS. 



[Feb., 1905. 



The Face of the Sky for February. 



By W. Shackleton, F.R..-\.S. 

 The Sun. — On the ist the Sun rises at 7.41, and sets at 

 4-47 ; on the 28th he rises at 6.50, and sets at 5.36. The 

 Sun is after the clock, the equation of time being 

 appro-ximately 14 mins. throughout the month. 



For plotting the positions of spot?, with respect to the 

 a.xis and equator, the following table may be used : — 



Axis inclined from N. Equator N. of 



point. Centre of disc. 



Date. 



Feb. 5 

 .. 15 

 .. 25 



13° 55' W. 



17° 35' w. 

 20° 40' \v. 



6-54' 

 7° II' 



A partial eclipse of the Moon takes place on February 

 19. In this country the Moon rises about half an hour 

 bsfore first contact with the shadow. 



Diagram abowinK Path of Moon IhrouKh the Earth's Shadow. 



Further particulars are as follows : 

 F"irst contact with Penumbra Fel 



.. I, „ Shadow 



Middle of Eclipse 

 Last contact with Shadow 



„ „ „ Penumbra 



Magnitude of Eclipse 0-410 (Moon's i3iarn. 



Moon rises at Greenwich, 5.16 p.m. 



Occi'LTATioNs. — The following are the occultations of 



the brighter stars visible at Green wich at convenient times. 



Diwpiwarancc. I Reappearance. 



4.41 p.m. 

 5-54 .. 

 7-0 ,, 

 8-7 ,. 

 919 .. 



Angle feom Angle from 



' Mean 



Time.' 



N. Ver- N. Ver- 



poinl. lex. point, lex. 



IJ..' 9' I Hull . 



13..' B.AX:. 1^1 



14.. I tir Taun 



ai.. n VirRJnitis 



pm. 



Thi; Planets. — Mercury is a morning star, rising about 

 an hour before the Sun for a few days early in the month ; 

 later, he is in too close pro.ximity with the Sun to be 

 observable. 



Venus is now the most brilliant object in the evening 

 sky, looking S.W. The planet is at greatest elongation 

 of 46^41' E. on the 14th, setting about y.io p.m. on the 

 1st and at 10.5 p.m. on the 2Sth. About the middle of 

 the month the apparent diameter of the planet is 25", 

 whilst the phase is "half moon," 0-516 of the disc being 

 illuminated ; her lustre, however, is increasing, as the 

 point of ma.ximum brilliancy is not attained until near 

 the end of next month. Throughout the month the 

 planet souths about 3 p.m. on each day, and is easy to 

 discern about this time even with the naked eye ; the 

 meridian altitude increases from 38- on the ist to 51 ' on 

 the 2Sth. The Moon is near the planet on the evening of 

 the 8th. being 3 20' S. of \'enus. 



Mars does not rise until after midnight. 



Jupiter is diminishing somewhat in brightness, and 

 getting more to the west, and sets about 10.45 P-"^- "6'^'' 

 the middle of the month; he is, however, very conveni- 

 ently situated for observation in the early evening. The 

 equatorial diameter of the planet is 37"-3 on the 13th, 

 whilst the polar diameter is 2"-4 smaller. The satellite 

 phenomena visible in this country are as follows : — 



" Oc. D." denotes the disappearance of the Satellite behind the disc, and 

 ** Oc. R." its re-appearance; *''rr. I." the ingress of a transit across the disc, 

 and " Tr. E." its egress ; " Sh. I." the ingress of a transit of the shadow across 

 the disc, and " Sh. E." its egress. 



Saturn is no longer observable, being in conjunction 

 with the Sun on the 12th. 



Uranus is unobservable. 



Neptune is on the meridian about 8,45 p.m. on the 14th ; 

 he is describing a short retrograde path in Gemini, and 

 can be found by reference to the star i^ Geminorum. 

 Right Ascension. Declination. 



Neptune (F"eb. I4). 6'' 24"" 17" . . N. 22" ly' 18" 



M Geminorum . . e"* 17"" 13' .. N. 22" 33' 37" 



Meteor Showers: — 



Variable Stars. — Algol maybe observed at minimum 

 on the 5th at 9.8 p.m., 8th at 5.57 p.m., 25th at 10.51 

 p.m., and 28th at 7.40 p.m. 



o Ceti (Mira) is due at a maximum on 25th February ; 

 its period, however, is somewhat irregular. 



