Moon Phase by Date

What are moon phases

Moon phases are the changing appearance of the illuminated portion of the Moon as seen from Earth, depending on the relative positions of the Sun, Earth, and Moon. A full cycle — from one new moon to the next — is called a synodic month and lasts approximately 29.53 days.

Why the Moon changes appearance

The Moon doesn't emit its own light — we only see the portion of its surface that's illuminated by the Sun and facing Earth. As the Moon orbits Earth, the angle between the Sun, Moon, and Earth changes, which changes the visible illuminated fraction of the lunar disk.

The 8 main moon phases

• 🌑 New Moon — the Moon isn't visible, its illuminated side faces away from Earth.
• 🌒 Waxing Crescent — a thin sliver of light appears on the right side (Northern Hemisphere).
• 🌓 First Quarter — exactly half the disk is illuminated.
• 🌔 Waxing Gibbous — more than half illuminated, approaching full.
• 🌕 Full Moon — the entire disk is fully illuminated.
• 🌖 Waning Gibbous — the illuminated portion begins to shrink.
• 🌗 Last Quarter — half the disk illuminated again, on the opposite side.
• 🌘 Waning Crescent — a thin sliver before the next new moon.

The Moon's influence on Earth

The Moon is responsible for ocean tides through gravitational pull. The strongest tides (spring tides) occur during new moon and full moon, when the Sun, Earth, and Moon align in a straight line and their gravitational forces combine.

Why knowing the moon phase matters

• Astronomical observation: full moon is worse for stargazing due to bright light; new moon is best.
• Gardening: some gardening traditions follow lunar calendars for planting.
• Fishing and hunting: some animal activity patterns are linked to moon phases.
• Cultural and religious holidays: many calendars (Islamic, Jewish) are based on lunar cycles.
• Photography: landscape photographers often plan shoots around the full moon for natural night lighting.

Lunar calendars across cultures

The Islamic calendar is entirely based on lunar cycles, so religious holidays (like Ramadan) shift each year relative to the Gregorian calendar. The Jewish calendar is lunisolar, combining lunar months with the solar year by adding leap months. Chinese New Year is also determined by the lunar calendar and falls on the second new moon after the winter solstice.

The calculation is based on the average synodic month length relative to a known new moon and provides accuracy within about ±1 day — sufficient for most practical and entertainment purposes.