First Quarter Moon

The Half Moon 

The half moon shows a face of plaintive sweetness
Ready and poised to wax or wane;
A fire of pale desire in incompleteness,
Tending to pleasure or to pain:--
Lo, while we gaze she rolleth on in fleetness
To perfect loss or perfect gain. 

Half bitterness we know, we know half sweetness;
This world is all on wax, on wane:
When shall completeness round time's incompleteness,
Fulfilling joy, fulfilling pain?
Lo, while we ask, life rolleth on in fleetness
To finished loss or finished gain.  

Christina Rossetti

It is impossible to deduce whether the half moon to which Ms. Rossetti refers in this poem is in its first or last quarter. And that's probably the point. Such ambiguity lends itself well to a metaphor of life's inevitable ups and downs, and our human inclination (whether chosen or fated) to view our changing lot as either half-empty, or half-full.

I'd venture a guess that most people today wouldn't be able to tell the difference between a first and last quarter moon. Up until a few years ago I certainly couldn't. Like most, I'd look up from time to time, notice a pale moon...maybe hanging out in the afternoon sky...and think, "Huh...there's the moon...cool." And that would be about it. Of course it doesn't take a whole lot more observation before you pick out a pattern or two. And then there are helpful tricks that can save you in a pinch. "DOC" is my favorite: A waxing "D" progresses to a full "O" moon, and then slowly shrinks away into a waning "C." Of course, the pattern is reversed for southern hemisphere observers. Fortunately "COD" is a word in either direction...at least in English.

The first quarter moon is a lovely sight. With its eastern edge illuminated and the terminator running straight down the middle of its face, a telescope or pair of binoculars will reveal the shadows of great mountain ranges spilling out over vast crater-pocked lava planes. Though my latest astronomy themed drawing interprets the lunar landscape with a good deal of artistic license, I did try to reference real features made visible at first quarter.

The Sea of Rains (Mare Imbrium) is the central focus. Framing some prominent craters (Archimedes, Aristillus, Autolycus, and Cassini), this ancient volcanic plain is edged from south to north by the Appenine and Caucasus mountains and capped by an "Alpine Valley" (admittedly exaggerated in my depiction). The northern Mare Frigoris (Sea of Cold) bleeds around Aristotle's crater and into the lakes of Death and Dreams, finally bringing the eye to rest on a Sea of Serenity at lower right. Forgive my wordy indulgence here. It's easy to get carried away by such tantalizing names. Exploring the lunar surface can feel like wandering through a poem.