Question 1

What is the difference between Syzygy and Conjunction?

Accepted Answer

A conjunction is an apparent close approach of two bodies on the sky as seen from a third; a syzygy is a genuine near-straight-line alignment of three. Conjunction is about appearance, syzygy about actual geometry — two objects can look adjacent without being lined up at all.

Question 2

How do I know if I mean Syzygy rather than Conjunction?

Accepted Answer

Readers who land here meaning Syzygy rather than Conjunction are usually searching for phrases like “what is a syzygy”, “word with three ys”, “celestial alignment word”.

Aspect	Syzygy	Conjunction
Bodies	Three	Two, plus observer
About	Real geometry	Apparent position
Produces	Eclipses, tides	A close pairing
Requires alignment	Yes	No

Side by side

Which one did you mean?

Syzygy

Read either one in full