A full moon occurs when the side of the Moon facing Earth is fully lit up by the Sun.

There are a few different types of unusual full moon types which include;

  •   Blood moon

  •   Supermoon

  •   Blue moon

  •   Harvest moon

Blood Moon

One meaning of a "blood moon" is based on its red glow. This blood moon occurs during a total lunar eclipse. During a total lunar eclipse, Earth lines up between the Moon and the Sun. This hides the Moon from the sunlight.

When this happens, the only light that reaches the Moon's surface is from the edges of the Earth's atmosphere. The air molecules from Earth's atmosphere scatter out most of the blue light. The remaining light reflects onto the Moon's surface with a red glow, making the Moon appear red in the night sky.

Supermoon

It appears to us as a larger-than-usual Moon in our night sky. A supermoon looks larger just because it's a bit closer to Earth and is actually just a nickname for what astronomers call a perigean full moon – a moon that is full and at its closest point in its orbit around Earth.

Blue Moon

When you hear someone say, "Once in a blue moon …" you know they are talking about something rare. A blue moon is not blue in color. In fact, a blue moon does not look any different than a regular, monthly full moon.

Rather, a blue moon is special because it is the "extra" Moon in a season with four full moons. This usually only happens every two-and-a-half years. Since the 1940s, the term "blue moon" has also been used for the second full moon in a calendar month. This usually happens only every two-and-a-half years.

Harvest Moon

It refers to the full, bright Moon that occurs closest to the start of autumn. The name dates from the time before electricity, when farmers depended on the Moon's light to harvest their crops late into the night. The Moon's light was particularly important during fall, when harvests are the largest.

SOURCE: Space Place Nasa