The Phases of the Moon

The Moon has eight phases in a lunar month: four primary and four intermediate phases.

Illustration of the eight phases of the Moon with an arrow showing the order they appear in, seen from Earth. — A Moon cycle, or a lunation, is the time the Moon travels through its lunar phases.
©timeanddate.com

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Moon Phases in Order

The eight Moon phases of a lunar month are divided into four primary and four intermediate (waxing and waning) Moon phases:

Primary Moon phases happen at a specific moment in time, while the time between these moments are the intermediate Moon phases. The lunar cycle lasts about 29.5 days, just under a calendar month.

Lunar calendar: next Full Moon and New Moon phase

New Moon

Moon phase: primary
Moonrise: around sunrise | Moonset: around sunset
Illumination: 0% (approx)
Position in space: the Moon is between the Sun and Earth

If the Moon’s path crosses the plane of Earth’s orbit around the Sun (the ecliptic) while the Sun, Moon, and Earth are aligned at New Moon, a solar eclipse happens somewhere in the world.

Why the illumination doesn’t quite drop to 0%

Side-by-side illustration of the New Moon as seen from space where the Sun, the Moon, and the Earth are in a line. A 0% lit up Moon is shown on the side to show how it looks from Earth. — New Moon: The Moon is between the Sun and Earth. Only the dark unlit side of the Moon is facing toward us.
© timeanddate.com

Waxing Crescent Moon

Moon phase: intermediate
Moonrise: morning | Moonset: afternoon
Illumination: 0% to 50% (approx)
Orientation: the lit part appears on the right side in the Northern Hemisphere,
and the left side in the Southern Hemisphere
Position in space: moving from New Moon to First Quarter Moon

The Crescent phases can be a good time to see Earthshine, when sunlight reflected from Earth gives the dark areas of the Moon a faint glow.

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First Quarter Moon (Half Moon)

Moon phase: primary
Moonrise: around midday | Moonset: around midnight
Illumination: 50% (approx)
Orientation: the lit part appears on the right side in the Northern Hemisphere,
and the left side in the Southern Hemisphere
Position in space: the Moon has gone one quarter of the way around Earth

Look for the First Quarter Moon in the blue afternoon sky.

A Quarter Moon isn’t exactly 50% illuminated

Side-by-side illustration of the First Quarter Moon as seen from space. A 50% lit up Moon is shown on the side to show how it looks from Earth. — First Quarter Moon: The Moon is 90 degrees from the Sun, and half of the Moon’s surface facing us is lit up.
© timeanddate.com

Waxing Gibbous Moon

Moon phase: intermediate
Moonrise: afternoon | Moonset: early morning
Illumination: 50% to 100% (approx)
Orientation: the lit part appears on the right side in the Northern Hemisphere,
and the left side in the Southern Hemisphere
Position in space: moving from First Quarter to Full Moon

A couple of days into the Waxing Gibbous Moon phase, you can see the Golden Handle.

Full Moon

Moon phase: primary
Moonrise: around sunset | Moonset: around sunrise
Illumination: 100% (approx)
Position in space: the Moon and the Sun are on opposite sides of Earth

If the Moon’s path crosses the plane of Earth’s orbit around the Sun (the ecliptic) while the Sun, Earth, and Moon are aligned at Full Moon, a lunar eclipse happens on the night side of Earth.

Side-by-side illustration of the Full Moon as seen from space where the Sun, Earth, and the Moon are in a line. Also, a 100% lit up Moon is shown on the side to show how it looks from Earth. — Full Moon: The Moon and the Sun are on opposite sides of Earth, and the side facing us is fully lit up.
© timeanddate.com

Waning Gibbous Moon

Moon phase: intermediate
Moonrise: evening | Moonset: morning
Illumination: 100% to 50% (approx)
Orientation: the lit part appears on the left side in the Northern Hemisphere,
and the right side in the Southern Hemisphere
Position in space: moving from Full Moon to Third Quarter Moon

The Moon can still look quite full a few days after Full Moon in the Waning Gibbous phase.

Third Quarter Moon (Half Moon)

Moon phase: primary
Moonrise: around midnight | Moonset: around midday
Illumination: 50% (approx)
Orientation: the lit part appears on the left side in the Northern Hemisphere,
and the right side in the Southern Hemisphere
Position in space: the Moon has gone three quarters of the way on its orbit around Earth

The Third Quarter Moon begins the last quarter of the lunar cycle.

Side-by-side illustration of the Third Quarter Moon as seen from space. A 50% lit up Moon is shown on the side to show how it looks from Earth. — Third Quarter: The Moon has completed three quarters of its orbit around Earth, and half of its surface facing us is lit up.
© timeanddate.com

Waning Crescent Moon

Moon phase: intermediate
Moonrise: early morning | Moonset: afternoon
Illumination: 50% to 0% (approx)
Orientation: the lit part appears on the left side in the Northern Hemisphere,
and the right side in the Southern Hemisphere
Position in space: moving from Third Quarter to New Moon