In the article,
"The Mercury Retrograde Shadow Period: Prepare and Process," The AstroTwins bring awareness to the shadow period of every planet's retrograde cycle, giving examples of how Mercury's motion and position might be reflected in our everyday life, "Even though Mercury retrograde is over, Mercury retrograde’s shadow period is still in effect. The messenger planet began his three-week backspin through analytical Virgo on August 12, and then backed into attention-seeking Leo August 31. Mercury retrograde officially ended on September 5, but it still takes a couple weeks to shake off its juju.
"The “shadow period,” when Mercury’s rearward influence will inevitably make itself known. Mercury’s shadow began on July 24, 2017, and will linger until September 19, 2017. During this cycle, we should all take the necessary Mercury retrograde precautions..." The article explains how to find the shadow periods before and after a retrograde event, including a walk through with images of an ephemeris.
