Full moon
The Full Moon is the
lunar phase that occurs when the
Moon lies on the opposite side of
Earth from the
Sun. The Moon as seen from the surface of Earth is fully illuminated by the Sun at this time, presenting a "full" round disk to viewers on Earth. As always, only half the total surface of the Moon is illuminated.
Encyclopedia
The
Full Moon is the
lunar phase that occurs when the
Moon lies on the opposite side of
Earth from the
Sun. The Moon as seen from the surface of Earth is fully illuminated by the Sun at this time, presenting a "full" round disk to viewers on Earth. As always, only half the total surface of the Moon is illuminated.
Eclipses
A Full Moon is the only time when a
lunar eclipse is possible; at that time the Moon may move through the shadow cast by Earth. However, because of the tilt or inclination of the Moon's orbit around Earth relative to Earth's orbit around the Sun, the Moon usually passes to the north or south of Earth's shadow at Full Moon, so a lunar eclipse does not occur at every Full Moon.
Full Moons are generally a poor time to conduct
astronomical observations, since the bright reflected sunlight from the Moon overwhelms the dimmer light from stars.
Numbers and formulae
Although on average it takes only 27.322 days for the Moon to complete one orbit around Earth, it requires about two more days than that to again catch up with the Sun. On average, the number of days between Full Moons is about 29.5306 days. The actual number of days may differ from the average number by more than a half day. From one Full Moon to the next, the number of days in one
lunation can vary between 29.272 and 29.833 days.
The age and apparent size of the Full Moon vary in a cycle of just under 14 synodic months, which is called the Full moon cycle.
The combined date and time of Full Moon number
N, using a fictitious moon that moves at a strictly mean rate is approximately:
- D = 20.362954 + 29.5305888531 × N + 102.19 × 10-12 × N 2
- D is the number of days since 1 January 2000 00:00:00 UTC
Coordinated Universal Time is a high-precision atomic [i] time standard [i]....
,
- N is the count of full moons starting with zero as the first as the first Moon in the year 2000.
The
true Full Moon may differ from this by up to about 14.5 hours, due to the normal irregularity in the Moon's
Keplerian orbit, and due to the periodic perturbations on that Keplerian orbit by the Sun, the equatorial bulge of Earth, and nearby planets.
See the
New Moon page for a detailed explanation of the formula.
Folklore
Full Moons are traditionally associated with temporal
insomnia,
insanity and various magical phenomena such as lycanthropy. On a full moon, the
moon is in
opposition to the
sun, thus indicating that one's inner world of feelings and outer persona and expression may be in conflict with each other.
Psychologists have found that there is no strong evidence for effects on behaviour around Full Moon . They find that studies are not consistent, with some showing a positive effect, while others will show a negative effect. In one instance, the December 23, 2000 issue of the
British Medical Journal published two studies on dog bite admission to hospitals in
England and
Australia. The study of the Bradford Royal Infirmary found that dog bites were twice as common at Full Moon, while the study of public hospitals in Australia found they were less likely at Full Moon. Psychologists point out that there is a difference between
correlation and causation. The mere fact that two events happen at the same time doesn't mean that there is a cause and effect relationship between the two.
Neopagans hold a monthly ritual called an Esbat at each Full Moon.
Many people practicing traditional Chinese religions prepare their ritual offerings to their ancestors and deities on every Full Moon and New Moon.
Calendars
The
Hindu Calendars, Islamic calendar and the traditional Chinese calendar are both based on the phases of the Moon. Neither calendar, however, begins its months with the Full Moon.
In the Chinese calendar and some
hindu calendars, the Full Moon is always the middle of a month. The
Mid-Autumn Festival falls on the Full Moon of the eighth month. The
Lantern Festival falls on the first Full Moon of the year.We should also take a look at the Mayan calender as it takes its reference to that of a 13 moon cycle with one obscure day which falls on the 25th of July.Which means that our birthday falls on the same day every year.
Full Moon names
Folklore assigns a special name to each Full Moon, although the rule for determining which name will be assigned to which Moon has changed over time .
Modern practice is to assign the traditional names based on the
Gregorian calendar month in which the Full Moon falls. This frequently results in the same name as the older method would, and is far more convenient in practice. The older method of assigning names is based on seasons and quarters of the year.
Full Moon Names
| Month | English Names | Native American Names | Other Names Used | Hindu Names |
|---|
| January | Moon After Yule | Wolf Moon | Old Moon | Paush Purnima |
| February | Wolf Moon | Snow Moon | Hunger Moon | Magh Purnima |
| March | Lenten Moon | Worm Moon | Crow Moon, Crust Moon, Sugar Moon, Sap Moon | Holi |
| April | Egg Moon | Pink Moon | Sprouting Grass Moon, Fish Moon | Hanuman Jayanti |
| May | Milk Moon | Flower Moon | Corn Planting Moon | Buddha Purnima |
| June | Flower Moon | Strawberry Moon | Rose Moon, Hot Moon | Wat Purnima |
| July | Hay Moon | Buck Moon | Thunder Moon | Guru Purnima |
| August | Grain Moon | Sturgeon Moon | Red Moon, Green Corn Moon | Narali Purnima, Raksha bandhan |
| September | Fruit Moon | Harvest Moon | Corn Moon, Barley Moon | Bhadrapad Pornima |
| October | Harvest Moon | Hunter's Moon | Travel Moon, Dying Grass Moon, Blood Moon | Kojagiri or Sharad Pornima |
| November | Hunter's Moon | Beaver Moon | Frost Moon | Kartik Pornima |
| December | Moon Before Yule | Cold Moon | Long Nights Moon | Margashirsha Pornima |
| These are the traditional English names for each month's Full Moon and the names given by Native Americans in the northern and eastern United States. |
Traditionally these names corresponded to the seasons rather than calendar months. So, for instance, the Egg Moon would always be the first moon after March 21st, and the Lenten Moon would always be the last moon on or before March 21st.
The Blue moon
The origin of the folkloric term "Blue Moon" is complicated, because its meaning has changed over time. Modern practice is to name a Full Moon a
blue moon if it is the second of two Full Moons to occur in the same calendar month. The original meaning of
blue moon was the third Full Moon in a season when there were four Full Moons in that season.
See also
References
