Moon Phase Calculator - Current Moon Phase Today

A complete lunar cycle (synodic month) lasts approximately 29.53 days. This is the time it takes for the Moon to complete one orbit around Earth relative to the Sun, progressing through all eight phases from New Moon back to New Moon.

Moon phases are caused by the changing angle between the Sun, Earth, and Moon as the Moon orbits Earth. The Moon reflects sunlight, and we see different amounts of the illuminated half depending on the Moon's position. When the Moon is between Earth and the Sun, we see the dark side (New Moon). When Earth is between the Moon and Sun, we see the fully lit side (Full Moon).

Moon phase calculators using the synodic month algorithm are accurate to within a few hours for dates within a century of the reference point. They calculate phase based on the 29.53059-day lunar cycle from a known New Moon. For general purposes like gardening, fishing, or planning outdoor activities, this accuracy is more than sufficient. Professional astronomers use more precise ephemeris data for exact predictions.

Waxing means the visible illuminated portion is growing larger each night, occurring from New Moon to Full Moon. Waning means the illuminated portion is shrinking, occurring from Full Moon back to New Moon. In the Northern Hemisphere, waxing moons are lit on the right side, waning moons on the left. A memory aid: "waxing is growing, waning is going."

Yes. Moon phases directly correlate with tidal strength. During New Moon and Full Moon, the Sun and Moon align (syzygy), combining their gravitational forces to create spring tides with the highest high tides and lowest low tides. During First Quarter and Last Quarter, the Sun and Moon are at right angles (quadrature), producing neap tides with smaller tidal ranges.

The Moon's orientation appears flipped between hemispheres due to your viewing perspective on the spherical Earth. In the Northern Hemisphere, a waxing crescent is lit on the right; in the Southern Hemisphere, it's lit on the left. The actual phase and percentage illuminated are identical worldwide, but the visual orientation rotates based on your latitude.

Moon age is the number of days since the last New Moon, ranging from 0 to approximately 29.5. A moon age of 0 is New Moon, around 7.4 days is First Quarter, 14.8 days is Full Moon, and 22.1 days is Last Quarter. This metric helps determine the current position within the lunar cycle and is used in traditional calendars and tide predictions.

Yes. The moon phase (the percentage of the Moon that's illuminated) is the same at any given moment worldwide. However, the visual orientation of the Moon differs based on your latitude and time of observation. Observers in different time zones see the same phase at different local times, and Northern vs. Southern Hemisphere observers see the Moon flipped vertically.

A lunar month (synodic month) is 29.53 days - the time for the Moon to complete one phase cycle. A calendar month averages 30.44 days (365.25 / 12). This mismatch means moon phases don't repeat on the same calendar dates each year. Lunar calendars, used in some cultures and religions, align months with moon phases and add leap months to match the solar year.

The four primary phases (New, First Quarter, Full, Last Quarter) occur at specific geometric alignments. The four intermediate phases (Waxing Crescent, Waxing Gibbous, Waning Gibbous, Waning Crescent) describe the gradual transitions between primaries. The eight-phase system provides more precise communication about the Moon's appearance. Some systems use even more phases for finer granularity.

Despite popular belief, scientific studies have found no reliable evidence that moon phases affect human sleep, mood, mental health, birth rates, or surgical outcomes. The belief likely persists due to confirmation bias, cultural traditions, and the Moon's visual prominence. The term "lunacy" reflects historical misconceptions linking the Moon to mental illness, but modern research does not support this connection.

A blue moon is the second Full Moon in a single calendar month, occurring roughly every 2.7 years due to the mismatch between the 29.53-day lunar cycle and calendar months. Despite the name, blue moons don't appear blue in color. An alternative definition refers to the third Full Moon in a season with four Full Moons. The Moon can appear blue due to atmospheric particles from volcanic eruptions or wildfires, but this is unrelated to the blue moon phenomenon.

A complete lunar cycle (also called a synodic month) is approximately 29.53 days. During this period, the Moon goes through all eight phases: New Moon, Waxing Crescent, First Quarter, Waxing Gibbous, Full Moon, Waning Gibbous, Last Quarter, and Waning Crescent. This cycle represents the time it takes for the Moon to complete one orbit around Earth relative to the Sun.

Moon phases occur because the Moon reflects sunlight, and we see different amounts of the illuminated half as the Moon orbits Earth. When the Moon is between Earth and the Sun, we see the dark side (New Moon). When Earth is between the Moon and Sun, we see the fully illuminated side (Full Moon). The phases in between show different portions of the illuminated half.

Moon phase calculators using the synodic month algorithm are accurate to within a few hours for dates within a century of the reference point. They calculate phase based on the 29.53059-day lunar cycle from a known New Moon date. For precise astronomical predictions or eclipse timing, specialized ephemeris data is used, but for general purposes like gardening, fishing, or curiosity, standard calculators are sufficiently accurate.

Waxing means the visible illuminated portion of the Moon is growing larger each night, occurring from New Moon to Full Moon. Waning means the illuminated portion is shrinking, occurring from Full Moon back to New Moon. A simple way to remember: if the right side is lit (in the Northern Hemisphere), it's waxing; if the left side is lit, it's waning.

Yes. Moon phases directly correlate with tidal strength. During New Moon and Full Moon (when the Sun, Earth, and Moon align), gravitational forces combine to create spring tides with the highest high tides and lowest low tides. During First Quarter and Last Quarter (when the Sun and Moon are at right angles), we get neap tides with smaller tidal ranges.

The Moon's orientation appears flipped between hemispheres due to your viewing angle on Earth. In the Northern Hemisphere, a waxing crescent is lit on the right side, while in the Southern Hemisphere, it's lit on the left. The actual phase (the percentage illuminated) is the same worldwide, but the visible orientation differs based on your latitude.

Moon age refers to the number of days since the last New Moon, ranging from 0 to approximately 29.5 days. A Moon age of 0 means New Moon, around 7.4 days is First Quarter, 14.8 days is Full Moon, and 22.1 days is Last Quarter. This measurement helps determine the current position within the lunar cycle.