MOON TOUR
THEOPHILUS
How to find one of the most striking but overlooked craters on the lunar surface
Lunar observers often feel frustrated during summer because the Moon’s low altitude means they have to see it through the murk and haze that lingers above the horizon, so the Moon often appears bloated and its image wobbles and warps in eyepieces. But the Moon is always a lovely sight through a telescope, so why not try and track down something you’ll almost certainly have seen before but not spent time looking at properly.
Set between the dark stain of Mare Nectaris to the southeast and Sinus Asperitatis in the north, Theophilus is one of the most striking craters on the whole of the Moon – or at least on the side that faces us. Named after the 23rd Pope of Alexandria, who made no friends in religious circles by ordering the slaying of 10,000 monks, the crater is best seen during the lunar month for four or five days after new Moon and just before it reaches last quarter, when it lies close to the terminator. During full Moon Theophilus’ features are washed out. It then looks more like a white smoke ring than a pit, but is still easy to see.