These aspects are often classified as “hard” and “soft”. The soft aspects are smooth and flowing relationships such as the trine and the sextile. The hard aspects are the more difficult aspects with some friction, including the square, the opposition and in some cases the conjunction. The energy of soft aspects flows naturally and easily between the planets in the relationship. The energy of hard aspects can cause friction or challenges, but this can lead to motivation and growth.
Many modern astrologers include the aspects that traditional astrologers did not use. The semi-sextile is the aspect representing 30° between the two planets. It is considered a soft aspect, like the sextile and the trine. The quincunx is the aspect when the planets are 150° apart. This is considered a hard aspect, like the square and opposition.
There are also astrologers that use other divisions of the circle like the quintile (1/5), the septile (1/7) and the novile (1/9). These are called minor aspects. The circle can actually be divided into any number of “slices”, and that is done in some forms of astrology such as Harmonic Astrology and Vibrational Astrology.
It is also important to note that the relationships visible in the astrology chart are based on longitude so the planets may not be next to each other in the sky. Astrologers who want to account for the latitude also consider the declination graphs and may use parallel and contra parallel aspects.
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