“Mercury is the smallest and closest to the Sun of the eight planets in the Solar System, with an orbit of about 88 Earth days.” Wikipedia
Because Mercury is visible to the naked eye much of the year, humans have observed and recorded events associated with its position in the zodiac for millennia. Over the course of time, the planet Mercury has become associated with the archetype of the messenger.
The Astronomy, or what it is…
The phenomenon known as Mercury Retrograde occurs three times each year when, for about three weeks, Mercury travels in reverse motion against the backdrop of stars. Of course, it doesn’t really move backward, but only appears to do so from our point of view here on Earth.
Emerging from the far side of the Sun, it becomes an evening “star” seen low in the western sky after sunset and steadily reaches its maximum distance from the Sun (greatest elongation). It slows in its forward motion until it appears to stand still and then change direction. Continuing in its orbit, we see it approach the Sun, disappear while it crosses in front of the Sun, then reappear as a morning “star” heralding the dawn. As Mercury approaches its greatest elongation in the morning sky, it slows in its backward motion, stands still, then resumes its forward course.
All of the planets have a retrograde period, although not as frequently as does Mercury, the closest planet to the Sun. It is during the retrograde period that the planet in question is at perigee, or nearest the Earth.
The Astrology, or what it means…
In astrology Mercury rules communication, local travel and transportation, lower education, the intellect, thought processes, information, commerce and the trades, networks, and networking. It correlates to Hermes in Greek mythology and The Magician in the Tarot.
When Mercury is retrograde familiar channels of communications become tangled and confused. Expect delays and changes in plans. Use this time for researching and problem-solving. This is a great time to rewrite and edit, rework an old project or successfully repeat a task.
Reevaluate and reconsider, but hold final decisions and approvals until Mercury goes direct. The tendency is to initialize or finalize projects prematurely. The contents of verbal or written contracts and plans made now may later seem inadequate or unclear.
This is not a good time to buy on the spur of the moment without investigation. This is also not a good time to purchase electronic equipment or cars. Major purchases may be reduced in price after the retrograde period and you can save money by waiting. Major repairs or surgery performed now may be incomplete or plagued by unexpected repercussions.
Double-check and reconfirm every detail. Typed or written errors are easily overlooked, paperwork mislaid, appointments forgotten. Let your sense of humor overcome the challenge of unexpected adjustments.