 The sector is bordered by the first 'marker' star of the next constellation.The ecliptic plane divides the sectors into northern and southern regions in some cases e. g. Aries - Taurus or Aquarius - Pisces, so, for example, a planet with northern ecliptic latitude enters the constellation of Pisces much sooner than one with southern latitude - in this system.Concerning the astrological aspects, Synoptical Astrology focuses also on the arithmological characteristics of the natural number (positive integer) which divide the circle of 360 degrees.