PREDICTION OF OCCULTATIONS. 



27 



<p 



Log^ 



Log 5 







9.9971 



0.0000 



10 



9.9971 



0.0000 



20 



9-9973 



0.0002 



3° 



9-9975 



0.0004 



40 



9-9977 



0.0006 



5° 



9.9979 



0.0009 



60 



9.9982 



0.001 1 



7° 



9.9984 



0.0013 



1 



?-sin(f>' = Amid? 

 rcos<p' = 5cos<J> 



a = rcoscp'sin(7i — c 

 i = r cos cp' cos (7« — i 



logA = 9-4192 

 u = a 

 V ?" sin <p' cos Z? — JsinZ> 



OTsinilf = j(? — u 

 mcoaM = q — v 



u' = bf^ 



1/ = af^sinD 



wsiniV = p' — ?{' 

 /«cosiV= q' — V 



los/c = 9-4350 



cos4' = 



msm(M — N) 



^ = 270°— i\^q=4/ 

 "^ r^r 1KT^ ^sin4' 



n 71 



Upper signs for Immersion ; under signs for Emersion. 



^ u-*-tu' 

 tanP = 



v + t'd 

 V=Q + P 

 Mean Solar Time of the Star's apparent contact with the moon's limb ~ 



= T-d+t 

 Angle from North Point = Q 

 Angle from Vertex = V 



The angle ^ is to be taken out positive and less than 180°. If logmsin(Jf — N) 

 be greater than log k, cos >|/ will evidently be greater than 1, or impossible, and there 

 will be no occultation, except in some rare instances where the moon's limb passes 



