5000 Earth. General. 

 5050 Geodesy {see J 70). 



5100 Tjonffitude 1 , ni -a t oa\ 



Latitude |(«^^01oO;J80). 



Variatiou of Latitude, 



Pendulum Observatioji.s. {See also B 0170) 

 Disturbance of Giavit3\ {See also B 0180). 

 5400 Atmosphere. 



Absorption. {See C 3240, 3850 ; F 09G0). 

 Scintillation. {See C 3210). 

 Auroi'a. {See also F 1650). 

 Dust. {See F (1420). 

 5500 Intra-Mercuriai Planets. 

 5600 Mercury. General. 

 5610 Observations of position. 



5620 Constants, Dimensions, Diameter and Figure, Mass 



and Density. 

 5630 Distance {see also 4050). 



5640 Kotation, Configuration of Surface. 



5650 Atmosphere. 



5660 Temperature, Radiation, Brightness, Phases. 



5670 Transits, Occultation, {see also 4050, 4870). 



5680 Photographs, Maps and Drawings. 



5690 Spectrum {see 6820). 



5700 Venus. (As Mercury.) 

 5800 Mars. (As Mercury.) ' 

 5900 Minor Planets. (As above in order of reference 



number in each section.) 

 6000 Jupiter. 

 6100 Saturn. 

 6200 Uranus. 

 6300 Neptune 



6400 Extra-Neptunian Planets. 

 6500 Satellites of lutra-Mercurial Planets. 

 6510 Mercury 



6520 Venus. " 



6530 Mars. 



6540 Minor Planets. 



6550 Jupiter. 



6560 Saturn (and Ring System). 



6570 Uranus. 



6580 Neptune. 



6590 Exti^a-Xeptunian. 



6600 Comets. General, Physical appearance, Families. 



Discovery. 



Elements of orbit. 



Ephemerides. 



Observations of position. 



Physical appearance, tails, &c. 



Spectrum {see 6920). 

 [No registration numbers. Reference to Comet by permanent r umber and year]. 



