The 29.53-day lunar clock

Lunar Age Wheel

Read the Moon's current lunar day, waxing or waning direction, illumination and next major phase at a glance.

Lunar age wheel for 15 October 2026The marker shows lunar day 4.5 moving towards full moon. NEWFIRSTFULLLAST LUNAR DAY4.5Waxing Crescent
Thursday, 15 October 2026

🌒 Waxing Crescent

The illuminated portion is waxing.

Lunar age4.5 days
Illuminated21.7%
Cycle complete15.4%
Next major phaseFirst Quarter18 Oct, 16:12 UTC

The age is measured from the most recent new moon around the average 29.53-day synodic cycle. Phase times are calculated astronomical estimates.

How to read the dial

One orbit, a changing view

The wheel begins at new moon, travels clockwise through first quarter to full moon, then continues through last quarter and returns to new moon.

Lunar age is the time since new moon. Waxing means the illuminated portion visible from Earth is growing; waning means it is shrinking. The Moon itself is always half lit by the Sun—our viewing angle creates the phases.

The Moon phase cycle around EarthSunlight illuminates half of the Moon while the view from Earth changes around the orbit.NewFirst quarterFullLast quarter
A clock older than clocks

People have counted lunar days for millennia

Months followed the Moon

Many early calendars organised time around the easily observed sequence from crescent to full moon and back again.

The synodic month

The cycle from one new moon to the next averages about 29.53 days because Earth and Moon both move around the Sun.

Geometry behind the graphic

Today the phase is calculated from the changing angle between the Sun, Moon and Earth rather than appearance alone.

Phase background: NASA Moon phases. ChronoWaves presents calculated estimates for education and skywatching.