Astrology is not fatalistic – the stars do not foretell you future in such detail that you have no control over your life. Your chart is a map, pointing out areas that may be difficult, and areas that you will find easy. Your destiny, however, is up to you. If you want to climb a mountain, a map is very useful – but even if you take the difficult path you can still reach the summit (and conversely, you can take an easy route and still break your leg). If you have a difficult opposition in your birth chart (this is often called your natal chart), it doesn’t mean that you will suffer for the rest of your life – instead, the chart is pointing out an area that you need to work on. The most difficult combinations in a chart represent lessons to learn, and a challenging aspect is just that; a challenge for you to overcome by achieving balance between apparently conflicting parts of your personality.

Your birth chart is a profile of you as an individual, a map of what you find easy and what you find difficult. However, life is not fixed; we all have ups and downs in life, and these are indicated in astrology not just by your birth chart, but by transits and progressions.

A transit is simply a snapshot of where the planets are right now – as a planet moves around the Sun, it will pass through each sign of the zodiac. At certain times, the transiting planet will make an aspect to one of your natal planets, and for the duration of this transit it will feel as though that planet is part of your chart.

Generally, when looking for future trends, astrologers ignore the “inner planets” of Sun, Moon, Mercury, Venus and Mars. The Moon, for example, whizzes through all twelve signs in a month, so you have a Moon transiting every single one of your natal planets every month. Similarly, the Sun transits every natal planet during the course of a year. These transits do have an effect, but their effect only lasts for a few days at most.

When it comes to the outer planets, though, a transit can make its impact felt for many months. To take an extreme example, Pluto can take up to thirty years to pass through a sign as it’s a very slowly moving planet. This means that a Pluto transit can easily last two or three years, and Pluto transits by their very nature tend to be traumatic.

Transits can cause interesting configurations in your chart for a while; for example, if you have two planets square to each other, then at some point in your life an outer planet will occupy a third position temporarily turning the configuration into a much more challenging T-square; during this time, you will notice the effect of the two natal planets much more strongly than usual. Similarly, two planets in trine to each other will become part of a Grand Trine for a while, and everything will run smoothly in the area of life that these planets represent for the duration. These outer transits can be used to make general predictions over the next few years about easy and difficult times ahead.

Progressions are a little more complicated, and based on the rather curious concept of “a year for a day”, so when looking at your fortieth year we look at the positions that the planets were in forty days after your birth. The outer planets have hardly moved at all, so whereas transits are used for outer planets, progressions are used for inner planets. It’s my belief that the effects of progressions are less strong than those of transits, and I only use them as a secondary backup to the information I get from transits of outer planets.