It’s no coincidence that the word “moon” looks like “month.” They share a Germanic base — plus, the moon’s cycle resets itself on average every 29.53 days. The period of time between new moons is known as the synodic month. (A new moon, also called a dark moon, is not visible to earthlings. It occurs when the moon’s orbit crosses exactly between the Earth and the sun.)
This month’s full moon is called the flower moon in English. Other religious and cultural traditions have different names for the flower moon. For example, in Algonquian, this full lunar phase is a called the strawberry moon.
This year’s flower moon, however, has an added component. For nearly four hours, a partial lunar eclipse will obscure half the moon. According to Space.com columnist Joe Rao, at its peak the moon will be “possibly tinged slightly with a mixture of faint orange and reddish hues.”
The moon will be crossing through the southern portion of the Earth’s shadow — also known as its umbra. (Notice the relation to “umbrella.”) Because of the moon’s southern position in the zodiac constellation Sagittarius, not everyone will have the best view of the eclipse. People who live on or near the Pacific Ocean should consider themselves lucky; those on the Atlantic, not as much.
The lunar cycle — which includes variants of waxing, waning, and gibbous phases — sometimes produces more than twelve full moons in a year. The most commonly known of these is a blue moon, the third full moon in a three-month calendrical season that has four full moons. Blue moons occur on average every 2.7 years, the next of which is due in August 2012.