Moon Phase & Solunar Calendar
Moon illumination and a simplified solunar estimate, based on the classic Solunar theory.
How this works
The moon phase and illumination percentage here come from straightforward astronomical calculation — the moon's position in its roughly 29.5-day cycle relative to the sun, not a proprietary formula. Illumination is highest at full moon (0% moon age or 50% through the cycle) and lowest at new moon.
What "Solunar theory" actually claims
Solunar theory, popularized by John Alden Knight in the 1920s, holds that game activity peaks around the moon's position overhead and underfoot, with secondary influence from moonrise and moonset — and separately, that a darker moon pushes more nocturnal activity into dawn and dusk since animals feed less efficiently by moonlight overnight. This calculator gives you the moon data; treat the "activity outlook" note as a widely cited pattern to weigh alongside weather, pressure, and rut timing — not a guarantee.
Frequently asked questions
Is solunar theory scientifically proven?
It's a widely cited pattern among hunters going back to the 1920s, not a rigorously proven scientific law — treat the activity outlook as one factor to weigh alongside weather, pressure, and rut timing rather than a guarantee.
What moon phase is considered best for hunting?
A darker moon (lower illumination) is often cited as producing stronger dawn and dusk movement, on the theory that animals feed less efficiently by moonlight overnight and shift more activity into twilight hours.
Does this predict exact major and minor feeding times?
This gives moon phase, illumination, and a simplified activity outlook rather than the detailed major/minor period times some dedicated solunar calendars calculate — pair it with the Legal Shooting Hours calculator for your actual sunrise and sunset.
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