420
Saturn will so pass on October 19th, 1885; that Uranus so passedon April 9th, 1882 ; and that Neptune , as we have previouslyexplained, would have done so in 1881, if its movements hadnot been perturbed; but that it actually was at one nearestposition to the Sun in March 1876, and will be so again in, orabout, 1887, or 1888.
In connection with any such supposed effects as those towhich we just now referred, it may also be remarked, that itcannot matter much whether, when any one of the aboveplanets is in Perihelion, the Earth is very nearly between itand the Sun , or not. For such is their comparatively slowmotion, that, if the Earth were, at the date in question, exactlynpon the opposite side of the Sun , Neptune would only havemoved through ^J^th of its orbit away from its Perihelion,Uranus through about jl^th, Saturn through about dyth, andJupiter through about -And, before the Earth would catchthem up and come between them and the Sun. In fact, evenJupiter would still be comparatively close, and all the otherswould be very close indeed, to Perihelion, when the Earth ,between six and seven months afterwards, would make itsnext especially near approach to them by passing betweenthem and the Sun .
It is rather to be noticed, and is much more to the point,that, if any such effect be produced, the Earth may be underits influence for a considerable time, since, as it goes round itswhole orbit it will be decidedly nearer to any one of theseplanets which may be about to pass, or may have just passed,through its Perihelion, than if the planet were in, or near to, itsAphelion.
For instance, Jupiter would, in the former case, be somethinglike 46,000,000 miles nearer to the Sun during the whole of theEarth 's year than in the latter case ; so that, instead of theEarth ’s distance from it varying, as it would near to its Aphe-lion passage, from about 414,000,000 miles to 600,000,000 milesduring the year, its greatest distance would be about 554,000,000miles, while its least distance would he reduced to about368,000,000 miles. In other words, its average distance allthe year through would be diminished by 46,000,000 miles.