In astrology, an aspect is an angle the planets make to each other in the horoscope, and 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 is a 90° aspect). The more exact that an aspect is, the stronger or more dominant it is said to be in shaping character or manifesting change.