As all scholars know, the moon in the sky once held a fainter moon of its own, which winked in and out of clarity at the edges of sight during only the days immediately surrounding the full moon. The common folk were most likely to refer to it as the Ghost Moon, but in proper scientific terminology it was called Desdemona, a relic of earlier scientists of more fancifully mythological bent believing the story about the Laughing Sylphs having tossed some poor girl into the sky after a fit of jealousy involving a godling and a remarkably verbose myrtle tree.
For obvious reasons, complete records of Desdemona are difficult to come by: there was little interest in referring to a celestial object of only modest beauty and less frequent appearance, not to mention the perfect regularity of its appearances leading to utterly no interest in meticulous tracking of its cycle. We know that it was imperfectly round, a sort of dull beige, and containing no pockmarks or other features worth recording. Nothing else was ever given to the records of the astronomers, even among the magi of the Orphan Tower. However, at some point after the destruction of Atlantis, Desdemona surely did disappear from the sky, and those scientists who were able to record anything in the midst of the evacuations and resettlements made a note of the first interesting thing the peripheral moon had ever done.
It is the theory of some that Desdemona crashed into the ground, taking out Atlantis, causing tidal waves and earth quakes and volcanic eruptions, and giving rise to the theory of Antipodal Reversal. This is plausible only on its surface, as any proper calculations regarding the distance between the land and Desdemona's original position would have shown that if such a large object had crashed into Atlantis, we would have been left with an enormous, half-crushed dome of rock protruding from the ocean where once that island lay. As there is no dome, there was no crash of Desdemona; the relative plausibility of Antipodal Reversal is left as a simple logical exercise for other scholars.
The more plausible theory to explain both the loss of Atlantis and the disappearance of Desdemona is the far more respectable science involving massive gravitational flux as created by the nation's infernal machines. No doubt this force tossed the moon far away into the sky, where it is no longer visible, while simultaneously pushing Atlantis down beneath the waves: one may demonstrate a similar process on a smaller scale by observing how a cart that moves suddenly forward will send a man balanced precariously atop it falling backward, away from the motion of the cart.
