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What’s special about a full moon?

Why does a full moon tug our heartstrings? And why does the moon on this night look full, in contrast to other other nights and other phases of the moon?

Yesterdays supermoon in Switzerland from Gianni Krattli Fine Art Photography.

October 2016 supermoon, seen from Switzerland by Gianni Krattli Fine Art Photography.

Next full moon happens on January 12, 2017 at 11:34 UTC. Translate to your time zone. That means the moon is fullest for us in the Americas on the night of January 11 (before dawn January 12).

Every full moon is special, as evidenced, in part, by the fact that skylore assigns names for each and every full moon. The January full moon is called the Old Moon or Moon After Yule here in the Northern Hemisphere. In the Southern Hemisphere, where it’s high summer now, this full moon is called the Hay Moon, Buck Moon, Thunder Moon or Mead Moon.

The moon is special for another reason. At full moon, we’re seeing all of the moon’s day side.

At full moon, the moon and sun are on a line, with Earth in between. It’s as though Earth is the fulcrum of a seesaw, and the moon and sun are sitting on either end of the seesaw. So as the sun sets in the west, the full moon rises. When the sun is below our feet at midnight, the full moon is highest in the sky. When the sun rises again at dawn, the full moon is setting.

We all love line-ups of things in the heavens. Could it be the alignment of the sun, Earth and moon that causes us to feel a special connection with the full moon?

This composite image captures the Hunter moon rise over the Manhattan skyline taken across the Hudson river from the Hoboken Pier C park waterfront. This image consists of 19 images stacked into one.

Gowrishankar Lakshminarayananw wrote: “This composite image captures the moonrise over the Manhattan skyline taken across the Hudson river from the Hoboken Pier C park waterfront. This image consists of 19 images stacked into one.”

And here’s another reason why the full moon is special. If there’s a lunar eclipse, it must happen at full moon. It’s only at the full moon phase that Earth’s shadow, extending opposite the sun, can fall on the moon’s face.

In many ways, a full moon is the opposite of a new moon. At both the new and full phases, the moon is on a line with the Earth and sun. At new moon, the moon is in the middle position along the line. At full moon, Earth is in the middle.

Full moon always comes about two weeks after new moon, when the moon is midway around in its orbit of Earth, as measured from one new moon to the next.

Marlene Hernandez in Aruba wrote:

Marlene Hernandez in Aruba wrote: “Had to wait for clouds to move. Love the moon, calmness and good vibes.”

As the moon orbits Earth, it changes phase in an orderly way. Follow these links to understand the various phases of the moon.

Four keys to understanding moon phases

Where’s the moon? Waxing crescent
Where’s the moon? First quarter
Where’s the moon? Waxing gibbous
What’s special about a full moon?
Where’s the moon? Waning gibbous
Where’s the moon? Last quarter
Where’s the moon? Waning crescent
Where’s the moon? New phase

Bottom line: A full moon looks full because it’s opposite Earth from the sun, showing us its fully lighted hemisphere or day side.

Can you tell me the full moon names?

Moon in 2017: Phases, cycles, eclipses, supermoons and more

Deborah Byrd

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