44 A. Hinrichs on the Density, Rotation, and Age of the Planets. 
Mass, Age. Correction. Corrected Age. 
Jupiter, 25 3 2°5 "5 | 
Saturn, 7 2 i 13 
Uranus, . 1 1 *] 9 
Neptune, 2 3 3 2°8 
This is already a much more regular series; the mean of the 
corrected ages for Jupiter and Saturn is ‘9, for Uranus and Nep- 
tune 1°8, or, whilst the uncorrected age of the former was greater 
than that of the latter, by this (very imperfect) correction for 
mass it is as one of Jupiter-Saturn to two of Uranus-Neptune. 
The conclusion seems therefore well-founded, that a more thor- 
ough investigation of the variation of » in time, tf possible at all, 
would give the age of the different planets as regularly increasing 
un. 
of our solar system, we shall find the following four laws: 
First Law. The nearest seconda approaches its primary with 
advancing age.—Expressing these distances in radii of the central 
ody, we have: 
Mercury, 80 rad. of the Sun. 
Moon SS ot =a 
? . 
Jupiter, Ist Moon, 6 “ « «& Jupiter. 
Saturn, Ist Moon, 4°“ & & Qaturn. 
thus showing a decrease with age. Uranus, having its moons 
proper measure of the closeness. We ha 
: Nept.-Ur. =1:115 Ur.-Saturn, 
. 4 
Ur.-Sat. =2'247 Sat.-Jupiter. | 
Sat.-Jup. =1'718 Jup.-Asteroid. 
Jup.-Ast. ==2°195 Ast.-Mars. 
Ast.-Mars ==2°195 Mars-Earth 
“a 
4h “ 
