Consider your place in history when the Sun conjoins with retrograde Mercury at 6:50 pm EDT Thursday, June 19. That will be the message when Mercury passes between Earth and the Sun for an interior (or, “inferior”) conjunction.
Besides the type of Thursday’s solar conjunction with Mercury, its place on the zodiac (28+ Gemini) and history associated with that place will combine to complete the message.
Mercury’s interior conjunctions always take place during its apparent reversals. It is an event that marks both the midpoint of Mercury’s retrograde period, and its top speed.
Sure enough, Thursday will be 12 days after Mercury stationed retrograde on June 7, and 12 days before the innermost planet resumes direct apparent motion on July 1.
Mercury’s apparent speed on June 19 will be just over half a degree per day, as fast as it will get during the 24 days it will take to backpedal less than 10 degrees on the zodiac. That’s about one-fourth of the speed Mercury reaches when it is in direct motion on the other side of the Sun for an exterior (or, “superior”) conjunction. That’s unusually slow.