•The ecliptic is defined by the plane of the
 Earth’s orbit
 •If the other planets are
 always found near the ecliptic, they must always be located
 near the plane of the Earth’s orbit – at most slightly above or below it.
 •The planes of their orbits around the sun must
 almost match the Earth’s
 •Their slight motions above and
 below the ecliptic means the match isn’t exact.  (Their orbits are slightly tilted relative
 to ours.)