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Retrograde Shadow Periods

If you have even a passing interest in astrology you have no doubt heard of retrograde planets and Mercury retrograde in particular. When, from our perspective on earth, a planet looks to be going backward, it is said to be retrograde. All the planets (but not the sun and moon) are capable of retrograde motion for various amounts of time.

When Mercury, which rules communication and transport among other things, is retrograde, we are told to act on the words with re as a prefix. Such words as redo, reapply, review, retrace, repair, recheck all apply. This is a time when going back over (just as the planet is going back over where it has just been) is advised, rather than moving forward.

With Mercury, the retrograde period lasts about 3 weeks. After those three weeks, you may think that it is now fine to move ahead with plans you may have put off because of the retrograde period.  However, it may not be smooth sailing just yet, as the retrograde planets have what are called shadow periods.

I have been caught in retrograde shadow periods, as I am sure many others have. You get through the retrograde period with no real mess-ups and breathe a sigh of relief, and then, it happens!

Something that seems to conform to the retrograde period happens and you shake your head and wonder why it is happening now; after all the retrograde period has just passed. You’ve likely just been caught in its shadow.

The shadow period takes into account at what zodiac degree a planet stationed (slowed to a stop before changing direction) retrograde, and the shadow period does not end until the planet has moved across that degree again.

Likewise, the planet will retrograde back to a zodiac degree prior to that which it started its retrograde motion and when the planet last passed over that degree in direct motion is when the shadow period starts.

Here is a little visual example I did of retrograde motion on video. When the car (planet) is blue it is in direct motion and out of the retrograde shadow. When it is grey it is in direct motion but in retrograde shadow. When it is red it is in retrograde motion.

Here is another example, on December 4, 2017, Mercury stationed retrograde at 29 degrees Sagittarius. It then retrograded until the 22nd of December when it stationed direct at 13 degrees of Sagittarius.

Mercury last crossed over 13 degrees of Sagittarius on November 14, 2017. So, we can say that the shadow period started on the 14th of November 2017.

Mercury stationed retrograde at 29 degrees and retrograded back to 13 degrees. As Mercury will be retracing its steps back to 13 degrees, the shadow period is considered to have started when Mercury first passed that degree in direct motion. Likewise, the shadow period is said to end when Mercury catches up to where it was when it first stationed retrograde (29° in this example).

When we look to see when Mercury will actually catch up to the degree it was at when it started its retrograde motion (29 degrees Sagittarius) we see that it will not cross that degree again until the 10th of January 2018.

Therefore the shadow period extends the dates that we need to be wary of Mercury being retrograde from November 14th, 2017 to January 10th, 2018. (All dates CST).

So, what about you? Have you found that you have had problems related to retrograde issues, Mercury is the best known and one of the easiest to notice, but this applies to all the planets.

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Born and bred in Brisbane, Australia, I have had a fascination with astrology since I was a child. Currently studying Hellenistic Astrology and incorporating it with modern astrology.