Red Planet, Red Moon

There was a lunar eclipse this morning and, by coincidence, Mars happens to be as close to earth as it's going to be for about thirty years. This offered a unique opportunity to capture both red objects in the sky at once.

A Syntaxia Mathematica

Ptolemy was not Arabic, but his legendary treatise is known to us as the Almagest, which is a transliteration of its Arabic title al-mjsty; literally, The Magestic.