There are eight traditional moon phases, which are:
- New Moon
- Waxing Crescent
- First Quarter
- Waxing Gibbous
- Full Moon
- Waning Gibbous
- Last Quarter
- Waning Crescent
Facts About the Moon's Phases
You can read much more detail in our Guide to Observing the Moon, but here are your essential facts about the phases of the moon.
Starting with the new moon, it takes 29.5 days for the moon to work its way to a full moon, then back down towards the next new one.
Moon Phase Names
Whilst the moon 'grows' from new (no surface illumination) to full (surface is 100% illuminated), it is called a waxing moon.
For the 14 days it takes for the full moon to thin and become the next new moon, it is known as a waning moon.
In a waxing moon, the right side of the moon is lit and its left side is dark. The opposite is true of a waning moon, i.e. the right side is dark and the left is lit.
When the moon is 'half full', it is either at first quarter (waxing moon) or last quarter (waning moon) - both are excellent times to view the moon through a telescope!
The final two words you need to learn are gibbous and crescent.
A gibbous moon is one which is more than half full but less than full, whilst a crescent moon is less than half full.
Moon Phase Times
It is the sun hitting different sides of the moon as it orbits Earth which creates the phases of the moon.
Interestingly, this creates some phases of the moon facts relating to the time of day they can be seen.
- New moons are up all day, sharing the sky with and opposite the sun.
- Waxing crescent moons rise after the sun in the morning and set after it in the evening
- The first quarter moon rises around midday and sets around midnight
- Waxing gibbous sees the moon rise in the afternoon and set in the early hours of the morning
- At full moon, the sun and moon do not share the sky - the moon rises as the sun sets and then sets the next morning as the sun rises
- A waning gibbous moon rises at night, before midnight, and is still out in the morning - but will set before midday.
- The last quarter moon mirrors the first: it rises at midnight and sets at midday
- Finally, the waning crescent moon rises in the early hours of the mornng, before the sun, and sets in the afternoon, also before the sun
- Bringing us back to a new moon and starting the moon phase cycle once more...
Moon Phase Pictures
Finally, let's see what it is we've been talking about: