Phase: Quick Facts

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Photos

Diagram showing the phases of the Moon as it orbits Earth, with labeled positions for new moon, waxing crescent, first quarter, waxing gibbous, full moon, waning gibbous, last quarter, and waning crescent. The Sun is on the right, and arrows illustrate sunlight direction, while angles indicate the Moon's position relative to Earth and Sun at each phase.

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Topics

Lunar phase Quadrature Full moon New moon waxing gibbous moon first quarter moon last quarter moon waning crescent moon waning gibbous moon waxing crescent moon Retrograde motion Anomaly Conjunction Constant of aberration Perihelion Aphelion Synodic period Opposition Sidereal period Perturbation