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Waning Gibbous Moon

This intermediate Moon phase starts after the Full Moon and lasts until half of the Moon's face remains lit up at the Third Quarter.

Illustration image

During the Waning Gibbous phase, the Moon shrinks from Full to Half Moon.

©iStockphoto.com/leospek

Next Waning Gibbous Moon

Starts: 24 Apr 2024, 07:48

Ends: 1 May 2024, 19:27

Times for the Waning Gibbous Moon vary by time zone. Times and dates are based on the local time in Hong Kong. Change location

With some exceptions, the Waning Gibbous Moon rises after sunset but before midnight and doesn’t set until after sunrise.

A Waning Moon Shrinks

The Waning Gibbous phase is when the lit-up part of the Moon shrinks from 99.9% to 50.1%. It starts just after Full Moon and lasts until the Third Quarter Moon.

Waning means that it is shrinking and getting smaller, while gibbous refers to the oval-to-round shape.

It can be challenging to differentiate the first stage of Waning Gibbous from a Full Moon when 98%-99% of the surface is illuminated.

Sun Lights Up the Moon

The Moon's surface reflects the Sun’s rays, and half of it is always illuminated by sunlight. Just how much of that light we can see from Earth varies every day, and we refer to this as a Moon phase.

The Waning Gibbous Moon in the daytime blue sky.

A Waning Gibbous Moon is often visible in the morning daytime sky.

©iStockphoto.com/Greenseas

Looks Different Around the Globe

The Moon phases are the same all over the world, both in the Northern and Southern Hemispheres. The same percentage of the Moon will be lit up no matter where on Earth you are.

The orientation of the Waning Gibbous Moon depends on the time, the date, your location, and the Moon's position in the sky. Exactly which part of the Moon is lit up—the top, bottom, or the side—also depends on how high the Moon is in the sky.

Illustration of the eight phases of the Moon with an arrow showing the order they appear in, seen from Earth.
Illustration of the eight phases of the Moon with an arrow showing the order they appear in, seen from Earth.

It takes around 29.5 days to move through the eight Moon phases.

©timeanddate.com

Lunar Month: A Repeating Moon Cycle

In western culture, we divide the lunar month into four primary and four intermediate Moon phases.

The Moon phases start with the invisible New Moon. The first visible Moon phase is the thin sliver of a Waxing Crescent Moon. Around a week later, half of the Moon’s surface is illuminated at First Quarter Moon.

The illuminated part continues to grow into a Waxing Gibbous Moon, until 14 to 15 days into the cycle, we see the entire face of the Moon lit up at Full Moon.

The illuminated part then gradually shrinks into a Waning Gibbous Moon, and when it reaches the Third Quarter, the opposite half from the First Quarter is illuminated. From there, it fades into a Waning Crescent Moon. Finally, the Moon disappears entirely from view into another New Moon phase, only to reemerge and repeat this cycle.

No Gibbous Moon in Calendars

There is no symbol for the Waning Gibbous Moon in calendars as it is an intermediate Moon phase. Only the four primary phases are shown in calendars with the following symbols:
symbol of a new moon = New Moon symbol of a First Quarter = First Quarter symbol of a Full Moon = Full Moon symbol of a Third quarter Moon = Third Quarter

The Moon illustration on our Moon phase pages changes as time passes and indicates more accurately, although not perfectly, which part of the Moon is illuminated.

Topics: Moon, Astronomy