A changing view of reflected sunlight
The Moon does not produce its own light. As it orbits Earth, we see changing portions of its sunlit half. That shifting view creates the phases. From one New Moon to the next takes about 29.5 days on average, longer than the Moon's roughly 27.3-day sidereal orbit because Earth is moving around the Sun too.
The growing half of the cycle
New Moon is followed by waxing crescent, First Quarter and waxing gibbous. At First Quarter, half the visible disk is illuminated; the name refers to progress through the cycle, not a quarter of the Moon being lit. In modern astrology, the growing phases are often used as metaphors for beginning, testing and developing ideas.
Full Moon and the fading light
The Full Moon appears when the Earth-facing disk is almost completely illuminated. Waning gibbous, Last Quarter and waning crescent follow before the cycle begins again. Reflection, revision and rest are common symbolic associations. They should not be mistaken for proven biological or psychological effects.
Try a thirty-day sky journal
Record the Moon's appearance, where you saw it and the time of observation. Notice how the Moon rises at different times as the cycle advances. Its orientation can look different from one hemisphere to another. You will learn more from direct observation than from a graphic that treats the Moon as fixed in one corner of the sky.
Keep astronomy and ritual in separate columns
A personal New Moon check-in or Full Moon review can be a meaningful routine. Its value may come from the time you set aside, rather than any causal lunar influence. NASA's phase resources are useful for the measurable astronomy; astrology supplies an optional cultural language.
FAQ
Why is a lunar month about 29.5 days?
The Sun-Earth-Moon geometry must realign while Earth continues around the Sun.
Does every Full Moon bring an eclipse?
No. The Moon's tilted orbit usually carries it above or below the alignment needed.
Verified sources
Astrology is a cultural and symbolic practice, not a scientifically established method for predicting personal outcomes.