I think the moon is fascinating. I admit it: I’m a moon nerd. I love it when I get a chance to view it in its various stages, and I enjoy learning about moon facts and folklore. I even have an app on my iPad that shows what phase the moon is in on any given day.
Many people think the moon cycle starts on the full moon, but it actually begins in the new moon phase, which is when you can’t see it. This is because the moon is actually up during the day; the rise and set times coincide with that of the sun so the moon is not visible to us.
When you start to see a small sliver in the early evening, right after the sun goes down, that is a waxing crescent. (Some traditions call this the new moon, and refer to the period with no visible moon as the dark moon.) Waxing is when it is getting bigger night after night until it reaches full, then it is waning until it comes back to the new moon phase.
The moon will be a crescent for about a week until it reaches the first quarter, which refers to the fact that the moon is a fourth of the way through it’s cycle. Sometimes people call this a half moon because you’re seeing half of the illuminated face. When it is between the quarter and full phases, it is called gibbous. (A friend often gets this wrong and refers to it humorously as a “giblet” or “gibbon” moon.)
Of course, everyone knows what a full moon looks like. This phase is great because the moon is out the entire night, so it’s the best time to schedule bonfire parties and the like. There is about a three-day window where the moon looks full. After that it is waning gibbous, then last quarter, waning crescent and then back to new.
The full moon closest to the Autumnal Equinox is called the Harvest Moon because the light enabled farmers to continue working uninterrupted into the night. The full moon after that, usually in October, is called the Hunter’s Moon. There are other names for full moons that can vary between different groups, whether European or Native American.
There is also the blue moon. In popular terminology, this is the second full moon in a calendar month. The moon cycle is 29.5 days, so it is just a little bit shorter than our calendar month, so sometimes there will be 13 full moons in a year, which means two in one calendar month.
Compare this to a black moon, which would be two new moons in a month.
How can you tell if the moon is waxing or waning? I learned a cute phrase: “Dog comes, cat goes.” When it is waxing, the crescent looks like a “D” for dog but when waning, the curve resembles a “C” for cat. It’s easy to remember because dogs (generally) come when called but cats don’t.
You can also tell the phase by the time of night that you see it. A waxing crescent is up in the early part of the evening. The first quarter moon is in bed before midnight and a waxing gibbous is up until the wee hours of the morning. The waning gibbous moon won’t start to be visible until later in the evening, and the last quarter doesn’t get up until after midnight. If you see a thin waning crescent, then it is in the hours before dawn.
Knowing the moon phases is helpful if you want to do any kind of stargazing. The annual Perseid meteor shower happened in mid-August, at the time of the waning crescent moon. This gave plenty of time through the night to see the shower. I regret not taking the time to make arrangements for viewing; I need to remind myself that doing interesting things is worth the inconvenience to get there.
There is all sorts of folklore out there about the moon, such as gardening according to the moon phases. This seems a bit too much like astrology for my taste, but apparently my maternal grandmother followed these guidelines and did quite well. There are superstitions of the moon having an effect on human behavior, but this has not been able to hold up to scientific scrutiny.
What we do know is that the moon is a really interesting thing to study. Read and learn about it, but most of all make the effort to get out there and look at it.