Aspects are formed as the planets revolve around the sun and are measured by looking at the angles formed between them. Certain angles (see below) are deemed to be helpful or benefic and others unhelpful or malefic. The more precise in time that the aspect is then the stronger the influence. It is also widely believed that an aspect is stronger while it is forming than when it is waning. The planets closer to the sun move much faster than the outer ones. For this reason the aspects between the outer planets (especially Uranus, Neptune and Pluto) may last for many years and so will be more important to society rather than to an individual. These aspects will not usually be analyzed in depth in a horoscope.
The Main Aspects
This occurs when two planets occupy the same degree of longitide, and will generally increase the prominence of those planets in the readings. This generally brings a positive influence but if the planet is unhelpful in the chart, this will increase its effect. A conjunction is usually effective within an orb of 5-8 degrees
Oppositions occur when two planets are 180 degrees of longitude apart. It will add tension to the interrelationship of the two planets concerned and like the conjunction will be effective within an orb of 5-8 degrees
The Trine aspects are the most helpful in a horoscope and occur when two planets are separated by 120 degrees of longitude. Trines will boost the good luck of a planet and sometimes are called the aspects of good fortune. A Trine to Jupiter for instance, would bring a double measure of that planets generosity and luck.
Squares are the aspects that everyone loves to hate and will be effective when planets are at 90 degrees of longitude to each other, within an orb of about 5 degrees. They indicate difficulties with the planets concerned and in a birth chart, these difficulties will often appear as a challenge to be overcome in life. Remember that your horoscope is NOT a recipe for how your life will turn out, but represents opportunities to be taken and hurdles to be overcome. People who overcome square aspects will gain much out of life.
Sextile aspects are like mini-Trines and occur when the planets are 60 degrees apart within plus or minus 1 degree. They bring good luck but not as much as the Trines. Even so, a sextile aspect should be seen as an opportunity to exploit some of the influence of the two planets. It will be very rare for anything to happen without your positive effort.
The more esoteric Aspects
Quintile 155 degrees – More energy
Bi Quintile 72 degrees – Invigorating
Semi Sextile 30 degrees – Slightly under pressure
Semi Square 45 degrees – Awkward
Quincunx 150 degrees – Under pressure
Sesquiquadrate 135 degrees – Slightly awkward