The buzz right now centers on an event (or non-event, depending on how you think of it) happening Aug. 23. When an astronomical season, which is about three months long, includes four "new moons" rather than three, the third one is sometimes called a Black Moon. This happens about once every 33 months.

This week, the cosmos is serving up a celestial twist: a rare “black moon” on August 23 — an event so mysterious that the moon itself disappears completely from view, even as it captures the world’s i...