Lunar Summary for April
In April 2026, there are 4 major lunar phases: Full Moon (Apr 2, 2026), Last Quarter (Apr 10, 2026), New Moon (Apr 17, 2026) & First Quarter (Apr 24, 2026).
Moon Phase Calendar FAQ
How are the moon phases calculated?
This calendar uses Jean Meeus' astronomical algorithm (Astronomical Algorithms, Chapter 49) with 25 periodic correction terms. It calculates new moon, full moon, and quarter moon times accurate to within approximately 2 minutes of official USNO data.
What is a lunar day?
A lunar day refers to the day within the current synodic month (the cycle from one new moon to the next), which lasts approximately 29.53 days. Day 0 begins at the new moon, and day ~14.8 is approximately the full moon.
When is the next full moon?
The exact date and time of the next full moon is shown in the calendar above. Major phase events (new moon, first quarter, full moon, last quarter) are highlighted with their precise UTC times.
What does illumination percentage mean?
Illumination shows how much of the Moon's visible surface is lit by the Sun. 0% means a new moon (completely dark), 50% means a quarter moon, and 100% means a full moon.
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