424 



Mr. J. R. Hind on Transits of Venus, [Apr. 20, 



and \ the longitude from Greenwich + E., — W., the reductions for paral- 

 lax will be obtained from 



d h m s t 



1st ext. cont.... June 7 17 3 43+[2-2198]p .sin Z-[2-5932] . p . cos I . cos(\+176 32). 

 1st int. cont. „ 17 22 35 + [2-2571 ]p . sin I- [2-5765] . p . cos I . cos(\+ 182 38). 

 2nd int. cont. „ 23 5 40-[2-5090]p . sin J+ [2-4353] . p . cos I . cos(\ + 47 17). 

 2nd ext. cont. „ 23 24 32- [2-4928]p . sin 1+ [2-4631] . p . cos I . cos(\+ 54 35). 



For the Royal Observatory, Greenwich, I find : — 



d h m 



First external contact, June 7 17 9 56 



„ internal „ „ 17 28 5 



Second internal „ „ 23 3 



external „ 23 22 



24 r 



15 J 



Mean times at 

 Greenwich. 



Therefore the entire transit will be visible at Greenwich. 



Similarly the elements of the transit of 2012 are found to be : — 



Greenwich mean time of conjunction in right ascension 2012, June 

 5 d 13 n 4 m 44 s. 3> 



Right ascension of Sun and Venus .... 



74° 31 



11-9 



Declination of Sun .... 



+ 22 40 



24-1 



„ Venus. . . . 



+ 22 50 



3-0 





2 



34-67 



,, „ Venus .... 



-1 



3770 



Horary motion in declination. Sun .... 



+ 



15-23 



„ „ Venus .... 



-0 



45-37 



Semidiameter of Sun .... 



15 



46-01 



„ Venus .... 





28-77 







8-76 







30-86 



Log. distance of Venus from the Earth.. 



9- 



46042 



Equation of time . . l m 19 s, & (additive to mean time). 

 Hence, for the centre of the earth, — 



First external contact 

 „ internal „ 



Second internal „ 

 „ external 



d 



June 5 



h m s 



10 22 11 at 40-3 from N. towards E. 

 10 39 56 at 37-8 



16 42 6 at 293-1 



17 Oat 290-5 



1 For the 

 I direct 

 image. 



And, with the same notation as before, I find for the reductions for 

 parallax, — 



d h m s , 



1st ext. cont. ... June 5 10 22 11 + [2-4536] p . sin I- [2-4582] .p . cos /. cos (X +41 28). 



1st int. cont. „ 10 39 56 + [2-4838] p. sin/- [2-4558] .p. cos I. cos (X+43 52). 



2ndint. cont. „ 16 42 6- [2-1301] p . sin /+ [2-5968] . p . cos I. cos (X-10 57). 



2ndext.cont. „ 17 0-[2-1158] p . sin /+ [2-5825 j ] . p . cos L cos (\- 6 28). 



