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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?

The moon looks full and round for several nights around full moon. C.B. Devgun caught this nearly full moon on Friday night – March 10, 2017 – from India.

Next full moon happens on March 12, 2017 at 14:54 UTC. Translate to your time zone.

A 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.

So, at full moon, we’re seeing all of the moon’s day side.

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? Especially when there’s an eclipse, as there was for the February 2017 full moon? In fact, a lunar eclipse must always 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.

February 10, 2017 full moon – while a penumbral eclipse is taking place – behind the Great Beds Lighthouse in the Raritan Bay, New Jersey (with airplane). Photo by John Entwistle Photography. See more photos of the February 2017 lunar eclipse.

Skylore assigns names for each and every full moon. The February full moon is called the Snow Moon, Hunger Moon, Wolf Moon here in the Northern Hemisphere. In the Southern Hemisphere, where it’s high summer now, this full moon is called the Grain Moon, Sturgeon Moon, Red Moon, Wyrt Moon, Corn Moon, Dog Moon, Barley Moon.

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.

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.

No matter where you are, it’s fun to watch the full moonrise. Gowrishankar Lakshminarayananw wrote: “This composite image captures the moonrise over the Manhattan (NYC) skyline taken across the Hudson river from the Hoboken Pier C park waterfront. This image consists of 19 images stacked into one.”

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