Page:The Solar System - Six Lectures - Lowell.djvu/125

From Wikisource
Jump to navigation Jump to search
This page has been validated.
  Jupiter and his Comets 107;

FIG. XV. ACTION OF JUPITER.
FIG. XV. ACTION OF JUPITER.

represents in amount and direction the comet's actual velocity in space. similarly denotes that of the planet, the two bodies meeting one another under the angle . will then represent the relative motion, in amount and direction, with which the comet approaches the planet.

The action of the planet is to turn the relative motion of the comet through an angle, say AOE, OA representing the in-coming asymptote of the relative orbit, OE the out-going one. EP or V' will then represent the absolute motion in space of the comet after the encounter. Similarly, if the comet passed behind the planet and was turned through the angle AOI, PI would be the new absolute velocity of the comet on leaving the planet.