Moonrise andmoonset are times when the upperlimb of theMoon appears above thehorizon and disappears below it, respectively. The exact times depend on thelunar phase anddeclination, as well as the observer's location. As viewed from outside thepolar circles, the Moon, like all othercelestial objects outside thecircumpolar circle, rises from theeastern half of the horizon and sets into thewestern half[1] due toEarth's rotation.[2]
SinceEarth rotates eastward, allcelestial objects outside thecircumpolar circle (including theSun, Moon, andstars) rise in the east and set in the west[2] for observers outside thepolar circles. Seasonal variation means that they sometimes rise in the east-northeast or east-southeast, and sometimes set in the west-southwest or west-northwest.[3] This north-south variation of the point along the horizon isbookended by twolunar standstills or turnarounds, the directions of which are sometimes depicted inarchaeoastronomical constructions.[4] It takes 18.6 years for the Moon to traverse this variation viewed from a vantage point on Earth.
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The Moon's position relative to Earth and the Sun determines the moonrise and moonset time. For example, a last quarter rises atmidnight and sets atnoon.[5] A waning gibbous is best seen from latenight to earlymorning.[6] The Moon rises 30 to 70 minutes (should be a fixed number, about 50 minutes, if it's the same 13 degrees) later eachday/night than the day/night before, due to the fact that the Moon moves 13 degrees every day. Hence, the Earth must move 13 degrees after completing one rotation for the Moon to be visible.[7]
| Lunar phase (illustration as seen from northern hemisphere) | Moonrise[a] | Culmination time (highest point) | Moonset | Best seen |
|---|---|---|---|---|
 New moon | 6 AM |  Noon | 6 PM | Not visible unless there is asolar eclipse |
 Waxing crescent | 9 AM |  Afternoon | 9 PM | Late morning to early evening |
 First quarter | 12 PM |  Sunset | 12 AM | Early evening to late night |
 Waxing gibbous | 3 PM |  Late evening | 3 AM | Early evening[8] and most of night |
 Full moon | 6 PM |  Midnight | 6 AM | Sunset to sunrise (all night), alunar eclipse is then possible |
 Waning gibbous | 9 PM |  Predawn | 9 AM | Most of night and early morning[6] |
 Last quarter | 12 AM |  Sunrise | 12 PM | Predawn to post-sunrise |
 Waning crescent | 3 AM | .jpeg) Late morning | 3 PM | Predawn to afternoon |
The Moon appears to be larger at moonrise or moonset due to an illusion. This illusion, known as theMoon illusion, is caused by an effect of thebrain. There is no definitive explanation for the Moon illusion. However, it is most likely because of how the brain perceives objects at different distances, and/or the distance we expect objects to be from us when they are near the horizon.[9]
The Moon appears to be more yellowish near the horizon. This is for the same reason the Sun and/or sky appears to be orangey-red at sunrise/sunset. When the Moon appears near the horizon, the light coming from it has to pass through more layers of atmosphere. This scatters the blue away, and leaves yellow, orange, and red.[10] This is also the reason the Moon appears red during a deep partial or totallunar eclipse.[11]
