Like most astrologers, I tend to be in awe of Pluto and Neptune as they make their stately, slow-motion passages through houses, signs and aspects. In doing that they illuminate the broad symphonic development of our lives over years and decades. With experience, we soon learn that they can knock us for a loop, sending us out of one relationship and into another, or into a new career, or off to live in a different part of the world. We can say the same for the other slow-moving planets – Uranus, Saturn, and Jupiter – as well as all of the progressions and solar arcs.

Heading sunward toward the center of the solar system from the august realms of the outer planets, we cross the asteroid belt and enter a far more frenetic zone. Like a carousel that's drunk one more cup of coffee than it should, Mars, Venus, and Mercury zoom frantically around the Sun – and around our charts. They’re powerful triggers, but what they actually trigger are those bigger developmental themes that were signaled by the slow moving bodies. Right there, we see one of the bedrock practical principles of working with planetary transits: the distinction between the fast bodies and the slow ones, so beautifully punctuated by the asteroid belt.