The same side of the Moon always faces Earth, but it looks different – even just a little bit every day – because sunlight reflects off the lunar surface, creating the different phases we see every month.
Eight lunar phases happen in order: new Moon, waxing crescent, first quarter, waxing gibbous, full moon, waning gibbous, third quarter and waning crescent.
If you look up at the Moon and wonder, “What phase of the Moon is that?” NASA also has this daily guide, which shows the phase and what features of the Moon you can see each night.
Here’s a look at all the lunar phases in more detail.
New Moon
A new Moon occurs when sunlight shines only on the Moon’s far side, sometimes referred to as the dark side of the Moon because it is the side we can’t see from Earth. During the new Moon, Earth’s only natural satellite appears nearly wholly dark.
A new Moon is an excellent time to try and spot meteors or look at the stars, as moonlight can’t wash out light from other astronomical objects.
Waxing crescent
During the lunar phase known as the waxing crescent, just a thin curve of the Moon is visible. As the lunar orbit continues casting more sunlight on the Moon, the crescent grows with sunlight on about 40% of the Moon. According to NASA, this phase is best viewed in the evening when the sky becomes darker.
First quarter
During the first quarter, the Moon is a fourth of the way through its monthly phases. About half of the Moon is illuminated by the Sun to viewers on Earth. It’s best to view a first quarter Moon when it’s high in the sky during the evening.
Waxing gibbous
About 90% of the Moon’s Earth-facing side is in view during the waxing gibbous phase. The Moon appears brighter in the sky. You can see the waxing Gibbous Moon phase when the sky is dark.
Full Moon
The bell of the monthly lunar ball happens when the Moon is opposite the Sun during its orbit around the Earth, fully illuminating the nearside of the Moon. This is the most well-known phase, possibly because many cultures name full Moons after seasonal changes that coincide with them.
If the Moon appears bigger and brighter than other full Moons, it could be a Supermoon, which happens when the satellite is at its closest point in orbit to Earth during the full Moon phase.
Waning gibbous
We’ve reached the other side of the lunar phases, as less light is cast onto the Moon. Still, the Moon appears between 90 and 60% full during the waning gibbous phase. As the Moon continues its orbit, with less sunlight, the Moon rises later each night.
Third quarter
Also known as a last-quarter Moon, a third-quarter Moon looks half-illuminated. Since we see only one side or half of the lunar surface, you see only a quarter of the Moon.
If you look up and see the Moon in the late morning, it could be a third-quarter Moon, which rises around midnight and sets around noon.
Waning crescent
The final phase before the cycle starts again with a new Moon is called waning crescent. Just a sliver of the Moon is not in shadow at this point.