Welcome to Inconstant Moon. Click on the links in the calendar pane above to discover what might be seen on a particular night, to switch to a different month, to call up the index of features, or to view the Cyclopedia Selenica - our reference library with articles, maps, bookstore and webguide.
The tour for any date relates to that night's viewing. So, for instance, clicking on the 12th of the month will show what can be observed on the evening of the 12th and/or the morning of the 13th.
In the nightly tours, many of the technical terms and all of the images are linked to extra notes which will appear in this pane, and clicking on the name of any physical feature will pull up a brief summary of its characteristics.
Because the moon's aspects and phases are irregular and uneven, and because you may be observing from anywhere in the world, it is impractical to produce a guide for exactly what you will see on a particular date. The guides are based on an "average" lunation (lunar cycle, new to full to new) and you may find that the visible features will be closer to those in the guide for the day before or the day after. Similarly, the same note may occasionally appear on two consecutive days. Although some of the features described are visible to the naked eye, most require a pair of binoculars (7 x 60 are ideal) and some really need a mounted telescope.