THE FACE OF THE SKY FOR MAY. 



Bv 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 L x refers to the 



equatorial zone, L 2 to the temperate zone, Ti, T a are the times of passage of the two zero meridians across the centre of the 



disc ; to find intermediate passages apply multiples of 9 h 50j m , 9 h 55^ m respectively. 



The letters m, e, stand for morning, evening. The day is taken as beginning at midnight. 



The Sun continues his Northward march. Sunrise during 

 May changes from 4-34 to 3-51 ; sunset from 7-20 to 8-3. 

 Its semi-diameter diminishes from 15' 54" to 15' 48". Out- 

 breaks of spots in high latitudes should be watched for. 



for Southern observers. Illumination one-half on 1st, full on 

 31st. Semi-diameter diminishes from 3i" to 2i". 



Venus is a morning star, at greatest brilliancy on 31st, 

 li° North of Moon on 4th. Semi-diameter diminishes from 



Mercury is a morning star till end of month, well-placed 29" to 19". At end of month 0-3 of disc is illuminated. 



Table 27. Occultations of stars by the Moon visible at Greenwich. 



The asterisk indicates the day following that given in the Date column. 



From New to Full disappearances take place at the Dark Limb, from Full to New reappearances. 



The occultation of Mars takes place in daylight, but from experience of a similar phenomenon I know that its observation will 



be possible with (say) a six-inch telescope if the weather is good. The occultation of Spica is also in daylight and as the Moon 



will have just risen it will be difficult to observe. 



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