Read lunar phase, illumination and upcoming quarters, with clear UTC times and a separate optional reflection practice.
What the tool calculates
Moon cycles shows geocentric lunar phase, the illuminated fraction and the next four quarter events. The calculation runs locally with Astronomy Engine 2.1.19. Supported instants are from 2000 through 2100. The diagram illustrates the phase; it is not a photograph or a prediction of the Moon’s exact appearance from your location.
Read the time before comparing dates
A lunar event happens at one instant, but the calendar date can differ between time zones. Results show UTC, and you can also display your browser’s time zone. A custom calculation requires a date, a time and an explicit UTC offset. “Z” means UTC. Check the offset that applied to your chosen date, especially where daylight saving time changes.
Phase and illumination are different fields
The phase angle locates the Moon within its cycle. Illumination describes the fraction of the visible disk that is lit. The same approximate illumination can occur while waxing or waning, so a percentage alone does not identify the stage. The named phase is a convenient grouping; the tool also shows the calculated angle.
Keep the reflection optional
You might use a new moon as a reminder to name an intention, or a full moon as a reminder to review it. That is a personal calendar ritual, not a scientific claim that a lunar phase determines your emotions, health or success. You can journal on any day and skip any association that does not help you.
Save what you actually noticed
Write an observation rather than a prediction: what you did, what changed and what remains uncertain. Save it to Moon cycles, then export its separate JSON backup if you want to move browsers or domains. A Moon backup is separate from the main Journal backup. The method details in the tool link to its library and astronomical reference tables.