A quasi-conjunction

Mercury comes to a conjunction with Saturn – no, not quite.

It is a quasi-conjunction. There is an appulse, a closest approach, of 3.4 degrees – but they separate again, so there is no conjunction in right ascension or in ecliptic longitude, no moment when one planet is directly north of the other. Quasi is Latin, “as if” or “almost”; perhaps because of association with “queasy,” it has a whiff of slyness or deceit.

In the picture, which will do for several evenings, arrows through the planets’ positions show their movement from 2 days before to 2 days after. You can see Mercury saying “Good evening, Grandpa!” and then sloping away.

The reason is that Mercury is going through the stationary moment (actually on Jan. 14) at the beginning of the apparent retrograde loop it makes as it swings between us and the Sun.

 

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4 thoughts on “A quasi-conjunction”

  1. Perhaps quasi is one of the 15 percent of the Romance words which entered English directly from Latin?But as 41 percent of English words come from French that’s more likely but obviously the French will have collected up quasi from Latin.

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