There are 3 major general techniques used to forecast the future in western astrology and several additional ones that are used in Vedic astrology. The 3 major techniques are: Transits, Progression, and Returns
What are Transits
Transits are perhaps the most intuitively obvious of the 3 major predictive techniques (transits, progressions, and returns) to understand. If I want to predict what will happen today to a particular person, then I compare the positions of the planets in the sky today with the positions of the planets in that person’s birth chart. The positions of the planets in the sky today are called the transiting planets. For example, if Sally’s natal Venus is at 10 degrees of Gemini and transiting Jupiter (the position of Jupiter today) is also at 10 degrees of Gemini, then transiting Jupiter is conjunct Sally’s natal Venus. Consequently, today is a Jupiter-Venus day for Sally, a good day to entertain people, go to parties, and generally have a relaxing, good time.
In addition to looking at aspects formed by the transiting planets to the natal planets, you can also study the placement of the transiting planets in the houses of the birth chart. Some astrologers also compare the zodiac signs of the transiting planets to the zodiac signs of the natal planets.
What are Progressions
There are several kinds of progressions. The most commonly used kind of progression is the day-for-a-year progression, also known as a secondary progression. A secondary progression is calculated by adding one day to the person’s birth date for each year of life. For example, suppose a person is born on June 15, 1982. On June 15, 1992 this person is 10 years old so you would add 10 days to the birth date to determine the influences 10 years later.
Therefore, the secondary progressed chart is a chart calculated for June 25, 1982. When the person is 20 years old (June 15, 2002), the secondary chart is calculated for 20 days after the birth date, which is July 5, 1982. The secondary progressed chart moves gradually so that the progressed chart for December 15, 1992 when the person is 10 1/2 years old is calculated for 10 1/2 days after birth.
A few astrologers also use a day-for-a-month, also known as a tertiary progression. In this kind of progressed chart, one day is added to the date of birth for each month of life.
Similar in concept to the tertiary progression is the minor progression, a chart that has one month added to the birth date for each year of life.
What are Returns?
A return is the moment that a transiting planet returns to the position it occupied at birth. For example, suppose that a person’s Sun position is 14 degrees 20 minutes of Cancer. At about the time of the person’s birth day each year the Sun will return to precisely this position of 14 degrees 20 minutes of Cancer. A chart constructed for this exact moment when the Sun returns to 14 degrees 20 minutes of Cancer is the solar return chart.
Similarly, the Moon will return to the position it had at birth approximately once a month. A chart constructed for this time is the lunar return chart.
The solar return and lunar return charts are used by many astrologers. Some astrologers have also experimented with charts of the times that other planets return to their natal position, so there is a Mercury return chart, a Venus return chart, etc.
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