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The Moon

The choice of flying over the mountains at night lies strictly with the pilot. Some pilots do, some don't. When you choose to fly at night over those scary old mountains it is beneficial to have the aid of the moon's light.

We don't all understand the lunar cycle, so the following trivia may be interesting.


Without attending astronomy classes we already know the moon has four main phases: new moon, waxing moon, full moon and waning moon. The moon cycle or lunar month is about 28 to 29½ days long, displaying 13 cycles during the year.

Terms and Definitions

Waxing - The time from the first day of the new moon to the full moon. You might think of this as a candle dripping. As it drips, it builds up. During this phase the moon looks like the letter "D." 

Waning - The time from the full moon to the new moon. During this phase the moon looks like the letter "C." 

Gibbous - You might run across the term waxing gibbous or waning gibbous. This is the "pregnant" time of the moon. More than half of its surface is illuminated approaching and departing from the full moon. (definition below)

New Moon

The new moon rises at sunrise and is visible in the sky all day.

Moonrise occurs about an hour later each day.


First Quarter

The waxing moon rises about noon and remains visible until about midnight.

The "D" shape stands for the French word, dure, meaning strong or enduring.


Full Moon

The full moon rises at sunset and is visible most of the night. It is not visible during the daytime.

Last Quarter

The waning moon rises about midnight and remains visible until about noon.

The "C" shape is "coy" or shyly retiring.


Main Entry:gib£bous
Pronunciation:*ji-b*s, *gi-
Etymology:Middle English, from Middle French gibbeux, from Late Latin gibbosus humpbacked, from Latin gibbus hump
Date:14th century

1 a : marked by convexity or swelling; b: of the moon or a planet : seen with more than half but not all of the apparent disk illuminated
2 : having a hump : HUMPBACKED
*Merriam-Webster's Collegiate Dictionary

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