Essentially a planet stops, and then turns retrograde when it catches up to, and then passes a slower moving planet.
Mercury moves faster than the Earth as they orbit around our sun, and — unlike other planets — the speed of its orbit often changing.
When Mercury is at its furthest point from the sun, it's also at the slowest point in its orbit, giving the earth a chance to catch up. This is where we spend the next three weeks watching the planetary dance as Mercury turning retrograde, moving in sync with the Earth.
So why of all the planets does Mercury seem to have the most noticeable effect on humans?
From an astrological standpoint, Mercury is the ruler of all forms of communication, honesty, clarity and even travel.
Those who believe in astrology will find a correlation between retrograde motion and sheer bad luck, because the planet is going against its natural movement. But in reality, the planet isn't changing its movement — it's just CATCHING UP TO MERCURY — and what's different is our perception of how the Earth is moving.
This is the third time this year that Mercury has stationed (stopped) in a water sign and gone retrograde, then prograde (direct) in an air sign. Today marks the beginning of a three-week period of Mercury Retrograde in the constellation Scorpio, before returning to Libra on Oct. 25th.
This is considered a time of reflection. You may notice that past issues are revisited, hashed out and made peace with. It's possible a new perspective will be gained from this awareness, if you work with the energies at play instead of against them.