Full Moon facts for kids

A full moon is a special time when the Moon looks completely round and bright from Earth. It happens about once a month. This is because the entire side of the Moon facing Earth is lit up by the Sun. It is one of the main phases of the Moon.

What is a Full Moon?

A full moon is when the Moon appears as a complete circle in the night sky. It is the brightest and largest the Moon looks during its monthly cycle. This happens because the side of the Moon facing Earth is fully lit by the Sun's rays.

How Does a Full Moon Happen?

The Moon orbits the Earth, and the Earth orbits the Sun. A full moon occurs when the Earth is positioned almost directly between the Sun and the Moon. This alignment allows the Sun's light to shine fully onto the Moon's surface that we can see.

Because of this alignment, the Moon rises around sunset and sets around sunrise. This means you can see a full moon all night long!

Special Full Moons

Sometimes, a full moon has a special name or appearance. These names often come from ancient traditions or how the Moon looks.

Supermoons

A supermoon happens when a full moon is also very close to Earth. The Moon's orbit around Earth is not a perfect circle. Sometimes it's closer, and sometimes it's farther away. When a full moon happens at the same time the Moon is closest to Earth, it looks a bit bigger and brighter than usual.

The supermoon of 14 November 2016 was 356,511 km (221,525 mi) away from the center of Earth. This occurs yearly.

Blood Moons

A blood moon is another name for a total lunar eclipse. During a total lunar eclipse, the Earth passes directly between the Sun and the Moon. This blocks direct sunlight from reaching the Moon. However, some sunlight still bends through Earth's atmosphere and reaches the Moon. This light often looks reddish or orange, making the Moon appear to glow with a deep, rusty color.

Direct sunlight is being blocked by the Earth, and the only light reaching it is sunlight refracted by Earth's atmosphere, producing a reddish color.

Harvest Moons

The harvest moon is the full moon that happens closest to the start of autumn. This moon often appears larger and more orange when it rises. This is because of how light travels through Earth's atmosphere when the Moon is low in the sky. Farmers historically used the extra light from this moon to work longer into the night, harvesting their crops.

A harvest moon. Its orange color is due to greater Rayleigh scattering as the Moon appears close above the horizon, rather than being unique to harvest moons.

Christmas Full Moons

Sometimes, a full moon can happen on a special holiday like Christmas Day. This is quite rare. The last time a full moon happened on Christmas Day for many parts of the world was in 2015. It's a fun coincidence when it occurs!

The December 2015 full moon coincided with Christmas day. This last occurred in 1977 (for the American timezones). A small horizontal libration is visible comparing their appearances. By the 19-year metonic cycle the full moon will repeat on Christmas day in 2034, 2053, 2072, and 2091.

Images for kids

• 

  A full moon rising, seen through the Belt of Venus

See also

In Spanish: Plenilunio para niños