All the planets orbiting the sun counter clockwise. Sometimes a planet seems to move against its natural course, from the point of view of earth. It is as if the planet is moving in the opposite direction – clockwise – that is what we call “Retrograde”.
The planets that are closer to us, Mercury and Venus have a short and quick orbit. And so it is often that we see them moving “behind” the sun. In fact they are moving forward, but from our point of view they seem to move in the opposite direction.
In addition there is another factor which is the movement of earth around the sun. Because of earth’s movement around the sun, the planets which are farther away from the sun (Jupiter, Saturn, Uranus and Neptune) would seem to move “backwards” half a year – and that is because of earth’s course “behind the sun” from the point of view of these planets! (I know it’s hard to understand in the beginning, it requires mathematical abilities and spatial vision which I luck… try to illustrate it with glasses on a table, or with balls on a carpet…)
Anyway (and without a lot of math this time)…
Each planet has a different length of retrograde phase: Mercury retrograde approximately 3 times a year for 3 weeks, Venus retrograde approximately every year and half for a month and a half. The retrograde phase of Jupiter, Saturn, Uranus and Neptune, lasts 5-6 month every year.
When we set important dates like wedding, opening a business etc. it is advisable to take these factors under account.
What is the meaning astrologically?
The influence of Mercury, Mars and Venus will be the most noticeable. But each planet has a different influence. During retrograde we will feel the less positive sides of each planet or that we feel a disruption in the course of things the planet is responsible of (Mercury-thinking, Venus –emotions etc.) Thus, during Mercury retrograde we should expect miscommunication, during Mars retrograde we should expect difficulty doing things, but very easily get into fights and disputes` during Venus retrograde it is not advisable to find a new relationship…