Months followed the Moon
Many early calendars organised time around the easily observed sequence from crescent to full moon and back again.
Type to search the site's pages.
Read the Moon's current lunar day, waxing or waning direction, illumination and next major phase at a glance.
The illuminated portion is waxing.
The age is measured from the most recent new moon around the average 29.53-day synodic cycle. Phase times are calculated astronomical estimates.
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.
Many early calendars organised time around the easily observed sequence from crescent to full moon and back again.
The cycle from one new moon to the next averages about 29.53 days because Earth and Moon both move around the Sun.
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.