SCENES ON THE PLANETS. 343 



seen when they have a dark belt for a background, and are least 

 easily visible when they appear against a bright portion of the 

 planet. Every observer should provide himself wuth a copy of the 

 American Ephemeris for the current year, wherein he will find 

 all the information needed to enable him to identify the various 

 satellites and to predict, by turning Washington mean time into 

 his own local time, the various phenomena of the transits and 

 eclipses. 



While a faithful study of the phenomena of Jupiter is likely 

 to lead the student to the conclusion that the greatest planet in 

 our system is not a suitable abode for life, yet the problem of its 

 future, always fascinating to the imagination, is open; and who- 

 soever may be disposed to record his observations in a systematic 

 manner may at least hope to render aid in the solution of that 

 problem. 



Saturn ranks next to Jupiter in attractiveness for the observer 

 with a telescope. The rings are almost as mystifying to-day as 

 they were in the time of Herschel. There is probably no single 

 telescopic view that can compare in 

 the power to excite wonder with that 

 of Saturn when the ring system is 

 not so widely opened but that both 

 poles of the -planet project beyond 

 it. One returns to it again and again 

 with unflagging interest, and the 

 beauty of the spectacle quite matches ^""^''^ ""^^.^""^1 ^'"^'^""'^ 

 its singularity. When Saturn is in 



view the owner of a telescope may become a recruiting officer for 

 astronomy by simply inviting his friends to gaze at the wonderful 

 planet. The silvery color of the ball, delicately chased with half- 

 visible shadings, merging one into another from the bright equa- 

 torial band to the bluish polar caps; the grand arch of the rings, 

 sweeping across the planet with a perceptible edging of shadow; 

 their sudden disappearance close to the margin of the ball, where 

 they go behind it and fall straightway into night; the manifest 

 contrast of brightness, if not of color, between the two principal 

 rings; the fine curve of the black line marking the 1,600-mile gap 

 between their edges — these are some of the elements of a picture 

 that can never fade from the memory of any one who has once be- 

 held it in its full glory. 



Saturn's moons are by no means so interesting to watch as are 

 those of Jupiter. Even the effect of their surprising number 

 (raised to nine by Professor Pickering's discovery last spring of a 

 new one which is almost -at the limit of visibility, and was found 



