Liberal Arts Blog — Cheshire Moon — a Treat for Early Birdsп
Liberal Arts Blog — Wednesday is the Joy of Science, Engineering, and Technology Day
Today’s Topic — Cheshire Moon — a Treat for Early Birds
The Cheshire moon (aka the smiling moon or boat moon) is one of four crescent moons. The two basic crescents are waxing (D-shaped) and waning (C-shaped). But sometimes the horns (also called “cusps”) of the crescent poke upward in a U-shape. That is the Cheshire Moon. At other times the horns point down — called a “reversed crescent.” What is going on here? Experts — please chime in. Correct, elaborate, elucidate.
THE BASIC EXPLANATION (Wikipedia)
1. “A wet moon occurs when the crescent Moon is low above the horizon and at a point more or less directly above the Sun’s (invisible) position below the horizon.”
2. “This in turn is determined by the positions of the Moon and Earth in their respective orbits, the inclinations of these orbits relative to one another and to Earth’s celestial equator. and the observer’s latitude on Earth.”
3. “Wet moons occur routinely in the tropics (where the Sun and Moon riseand set nearly vertically), but rarely in the polar regions (where the Sun and Moon rise and set at a glancing angle or not at all).”
NB: I have failed to find a good youtube video explaining the four types of crescent moon. Can anyone help? Is this a huge opportunity for fame and glory?
HAWAIIAN MYTHOLOGY — the “wet moon” and the “dry moon”
1. The U-shaped moon is called a “wet moon” in Hawaiian mythology because it looks like “a bowl that would fill up with rainwater.”
2. “The period when this is most common, January 20 to February 18, corresponds with Kaelo the Water Bearer in Hawaiian astrology and makes the Moon known as the “dripping wet moon”. As summer comes, the crescent shape shifts, pouring out the water and causing the summer rains.”
3. “After the “bowl” empties, it dries out and rights itself, creating the “dry moon”. However, others say that this is a wet moon because it permitted the water to pour out.”
WHEN DO YOU GET A CHANCE TO SEE THE CHESHIRE MOON? (Farmer’s Almanac)
1. “In the evenings during the spring (March, April, May), and in the mornings during the fall (September, October, November), for “temperate” (mid-northern) latitudes, the crescent Moon is oriented in such a manner so as to resemble a “smile” or “boat” with the “horns,” or “cusps,” of the crescent pointing straight up.”
2. “In contrast, in the evenings during the fall and in the mornings during the spring, the crescent Moon is turned roughly 90-degrees (sideways)…”
3. “Season of year and an observer’s latitude determine the angle the crescent Moon’s cusps make with the horizon. Around the time of the Vernal (Spring) equinox, the ecliptic — that imaginary in the sky that the Sun, Moon, and planets appear to follow in their respective paths against the background zodiacal signs — is oriented almost perpendicular to the western horizon. So the crescent moon in the evening sky (the “waxing” crescent) appears like a smile or a boat.”
FOOTNOTE — THE CHESHIRE CAT IN ALICE AND WONDERLAND
1.“Unlike a regular cat, this cat — “the Cheshire Cat”– can not only talk, but appears and disappears at will. This cat has the irritating habit of engaging Alice in confusing conversations, but its appearances and disappearances are made stranger by its ability to appear only partially.
2. “In one scene, the cat’s head appears without its body. In another the cat fades away until only its grin is visible.”
3. “Alice observes that she has seen a cat without a grin before, but never a grin without a cat.”
https://en.wikipedia.org/wiki/Wet_moon
What Is A Wet Moon or “Cheshire Moon”?
What are the names of full moons throughout the year?
http://lotsofmoons.blogspot.com/2015/01/what-is-cheshire-moon.html
A LINK TO THE LAST THREE YEARS OF POSTS ORGANIZED BY THEME:
PDF with headlines — Google Drive
YOUR TURN
Please share the coolest thing you learned this week related to science, engineering, or technology. Or, even better, the coolest or most important thing you learned in your life related to science and engineering.
This is your chance to make someone else’s day. Or to cement in your mind something that you might otherwise forget. Or to think more deeply about something dear to your heart. Continuity is key to depth of thought.
