Graphical Ephemeris

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A graphic portrayal of planetary positions as opposed to the method of giving their positions in tables as is the case in standard ephemerides. Graphical ephemerides help to gain a quick overview of planetary movements over a given period of time.

Sometimes a circular method is used whereby the twelve segments of the circle represent the twelve houses of the zodiac and lines charting the course of the planets emanate from the centre of the circle, i.e. at the beginning of the chosen period a planet is located in the centre and at the end on the perimeter. However, it is more common to have a rectangular diagram with linear time represented by horizontal coordinates running from left to right and vertical ones for the zodiac. The crossing of two (planetary) lines represents a conjunction of the planets involved. Any retrograde movement can quickly be identified by a line curving back on itself.

A so-called 45 degree ephemeris has only 45 (rather than 360) degrees. The zodiac is basically divided into 8 segments of 45 degrees which are then laid on top of each other. The intersections where two lines cross show all 45 degree aspects (Semi-Square) together with all other aspects divisible by 45 degrees; (Square = 90 degrees; Sesquisquare = 135 degrees; Opposition = 180 degrees), i.e. the most important analytical aspects.

If natal planets are entered into the graphic ephemeris (in the rectangular portrayal on horizontal lines at the degree in the natal chart), it is possible to see when transits occur where the lines of planetary transits cross the lines of natal ones.