A horoscope represents a snapshot of the sky at the moment of birth. The planets and signs are symbols, while the houses represent areas of life. By reading the placement of the planets in signs and houses, and the interactions of planets with each other, it is possible to discern character strengths and weaknesses. The chart helps explain why a person is the way they are, and why they do what they do. To the extent a person is aligned with the energy of their chart, there is happiness. The opposite is also true. An understanding of astrology helps people achieve the wisdom of the words on the entrance the Oracle of Delphi: Know Thyself.
While the planets are fixed in the natal chart at the moment of birth, in the sky they continue to move and form new connections with each other and with natal placements. These formations relay the energy of any given moment, and indicate activities to pursue and avoid, as well as areas of ease and struggle. As the famous astrologer Evangeline Adams once wrote: The lesson of astrology is to teach you nature’s intention as indicated by the planets; to deviate from it tends to failure, to know it gives power, to pursue it success.
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The natal chart of When Worlds Collide: 
Another Look at the Lunar Nodes, 
October 22, 2007; 8.56 am EDT