Moon Phase Calculator
Moon Phase Calculator
Discover the current phase, illumination, and age of the Moon for any specific date.
Report Bug For centuries, humanity has looked up at the night sky to track time, tides, and harvest seasons. The Moon, our celestial companion, shapeshifts through a precise cycle. The Moon Phase Calculator bridges ancient wisdom with modern astronomy. It determines exactly where the Moon is in its 29.5-day orbit relative to the Earth and Sun, telling you whether it is waxing, waning, or fully illuminated.
Whether you are a photographer chasing the perfect moonlight shot, a gardener following biodynamic planting rules, or simply curious, this tool reveals the Moon's current face.
🔭 Celestial Mechanics: The Synodic Month
The Moon doesn't change shape; only our view of its sunlit side changes. To calculate this mathematically, we use the "Synodic Month" average.
The Cycle Breakdown (0 to 29.5 Days):
- Day 0 (New Moon): 0% Illumination. The Moon is between Earth and Sun.
- Day 7.4 (First Quarter): 50% Illumination. Waxing (Growing).
- Day 14.8 (Full Moon): 100% Illumination. Earth is between Moon and Sun.
- Day 22.1 (Last Quarter): 50% Illumination. Waning (Shrinking).
🌌 Case Study: Tracking the "Wolf Moon"
Let's calculate the phase for a specific date to understand the illumination percentage and the "Age of the Moon."
Observation Note: A Full Moon is the only phase where the moon is directly opposite the Sun. This alignment creates the "Syzygy" effect, often leading to higher ocean tides known as Spring Tides.
Lunar Influence & Practical Applications
Why do people track the moon? It goes beyond astronomy:
- Gardening (Biodynamics): Many gardeners believe in planting above-ground crops during the Waxing Moon (increasing light) and root vegetables during the Waning Moon.
- Fishing & Hunting: Wildlife activity is often correlated with lunar transit times and phase luminosity (Solunar Theory).
- Photography: Knowing when the "Golden Hour" coincides with moonrise allows photographers to capture stunning landscapes.
Cosmic Queries (FAQs)
Does the Moon phase affect sleep or mood?
This is a debated topic. While folklore suggests the "Full Moon" causes erratic behavior (hence the word "Lunatic"), scientific studies show mixed results. However, some research indicates that human sleep duration can decrease slightly around the Full Moon due to increased nocturnal brightness.
What is the difference between Waxing and Waning?
Waxing means "growing." The illuminated part is increasing (heading towards Full Moon). In the Northern Hemisphere, the light grows from the right side. Waning means "shrinking." The light is decreasing (heading towards New Moon), and the shadow grows from the right.
Why do we see the same side of the Moon?
This is called "Tidal Locking." The Moon rotates on its axis at the exact same speed it orbits the Earth. Because the rotation and revolution periods are synchronized (roughly 27 days), one face is permanently locked facing Earth.
Is there a specific "best time" to cut hair based on the Moon?
According to Lunar Hair Care traditions, you should cut your hair during the Waxing Moon (New to Full) if you want it to grow back faster and thicker. Conversely, cut it during the Waning Moon if you want to maintain a short style for longer.
What is a "Blue Moon"?
A Blue Moon is not actually blue. It typically refers to the second Full Moon occurring within a single calendar month. Since the lunar cycle is 29.5 days and months are 30-31 days, this happens roughly once every 2.5 years.
