Moon calendar

Open the calendar

Open Astronomy tools with the telescope icon in the top bar, then choose Moon calendar. The calendar opens on the month containing the map’s selected date. Use the arrow buttons to move between months.

What each day shows

Each day combines the calculated lunar appearance with local observing context:

• Phase icon: a visual representation of the illuminated portion of the lunar disc.
• Illumination: the approximate percentage of the visible lunar disc illuminated by the Sun.
• Phase name: such as waxing crescent, first quarter, waxing gibbous, full Moon, waning gibbous or new Moon.
• Moonrise and moonset: approximate local times for the selected location. A dash means that event does not occur during that local calendar day.

On phones, the compact monthly grid displays the day number, phase icon and illumination so it remains legible at small sizes.

Set the sky map to a day

Select a day in the calendar to set the main sky map to that local calendar date. The currently chosen date is outlined. The map keeps its selected local time, so you can compare the same time of evening across different lunar phases. Open Today or the Observation Planner afterwards for a location-aware summary of the resulting observing conditions.

Calculation limits

Sky Map 2000 calculates phase, illumination and local Moon visibility in the browser from the selected date and observer location. Rise and set are approximate geometric times; they can differ slightly from an observed event because the real horizon, atmospheric refraction, buildings, terrain and the exact observing position are not modelled. Treat the calendar as a planning guide, then check the sky and your local horizon before an observing session.