HELIOCEXTRIC PLACES OF THE PLANET JUPITER. 



By Robert T. A. Ixnes, F.R.A.S. 



ATons. A. Gaillot of the Paris Observatory has called my 

 attention to the fact that the comparison between the heliocen- 

 tric places of the planet Jupiter derived from the Nautical 

 Almanac and the Connaissancc dcs Temps given in my paper on 

 Lc I ^ err lev's Theory of the Motions of Jupiter and Saturn* is 

 not exact. He points out that the heliocentric places furnished 

 by the Connalssance des Temfs are corrected for nutation, whilst 

 those of the Xautlcal .llmanac are not. and that if we compare 

 the right ascensions there will be a better accordance. Mons. 

 Gaillot further states that, about the dates I have used, Le 

 \'"errier's Tables represent the motion of Jupiter as well if not 

 better tlian those of Hill, but that this is accidental, and in a 

 general manner comparison is more favourable to Hill's Tables. 



I have therefore revised my little table and somewhat extended 

 it. The places from the Connalssance des Temps have been 

 brought to Greenwich Noon by multiplying the daily motion 

 bv -L 0.00649 ( — 9m. 20.9s. of E.Long.), and the *' Obs." are 

 the Xautlcal Almanac places corrected by photographic results 

 obtained at the Greenwich Observatory and published year by 

 year in the ^lonthly Notices of the Royal Astronomical Society. 



*Report S A. Association for Advancement of Science, Cape Town, 1910, 

 p. 104. 



