Combust (astrological aspect)

In astrology, an aspect is an angle the planets make to each other in the horoscope, also to the ascendant, midheaven, descendant, lower midheaven, and other points of astrological interest. Aspects are measured by the angular distance in degrees and minutes of ecliptic longitude between two points, as viewed from Earth. According to astrological tradition, they indicate the timing of transitions and developmental changes in the lives of people and affairs relative to the Earth.

As an example, if an astrologer creates a horoscope that shows the apparent positions of the celestial bodies at the time of a person's birth (a natal chart), and the angular distance between Mars and Venus is 92° of arc, the chart is said to have the aspect "Venus square Mars" with an orb of 2° (i.e., it is 2° away from being an exact square; a square being a 90° aspect). The more exact an aspect, the stronger or more dominant it is said to be in shaping character or manifesting change.

In medieval astrology, certain aspects, like certain planets, were considered to be either favorable (benefic) or unfavorable (malefic). Modern usage places less emphasis on these fatalistic distinctions. The more modern (but still unscientific) approach to astrological aspects is exemplified by research on astrological harmonics, of which John Addey was a major proponent, and which Johannes Kepler earlier advocated in his book Harmonice Mundi in 1619. But even in modern times, the aspects are divided into hard aspects or easy aspects. Major hard aspects being the square and opposition and the easy aspects as trine and sextile. The conjunction can be in either category depending on the planets that are connected.

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