My first photo ever published in a daily newspaper showed my landlord tapping the big maple tree outside his home. I’m guessing the month was March, the traditional time for lovers of maple syrup to drill a hole in a tree, tap in the spile and hang a bucket to collect the sap. Native peoples call it the sugarbush season and boiling the sap down into sweet syrup has been an important part of American culture since before there was an America. It’s no surprise that certain tribes named the March full moon the Full Sap Moon.
It has other names, too including Full Crust Moon, for the hardened snow crust that forms after repeated thawing and refreezing, and Full Worm Moon, recalling the return of the earthworms. While it’s a little too early for that here in northern Minnesota, it’s never too early to enjoy the full moon rising. Use this moonrise calculator to find out when the moon comes up for your town, and if it’s clear tonight, set aside a half hour to contemplate the orange orb. The moon will rise almost due east in the constellation Virgo around sunset and remain visible the entire night.
I like to bring a pair of binoculars with me for moonrises to better appreciate the interesting atmospheric effects that can ripple and shimmer the moon’s outline, squeeze it into an oval and color its edges purple and green. Our sightline to the moon passes through the lowest, densest part of the air column across hundreds of horizontal miles. Changes in air temperatures and jumbled up winds across such a large distance greatly affect the moon’s appearance. Refraction, the bending of light to different degrees according to the density or “thickness” of the air is responsible for the moon’s out-of-round shape.
The bottom of the atmosphere also contains the most dust, salt and industrial pollutants which scatter away the cooler blues and greens from moonlight, giving it a mellow, pink-orange glow. Watch for these things tonight while relaxing at tonight’s rising of the Sap Moon.