last quarter
Noun: 1. A specific lunar phase: The "last quarter" is the phase of the Moon that occurs roughly three weeks after the new moon. During this phase, exactly half of the Moon's visible surface appears illuminated (the left half from the perspective of an observer in the Northern Hemisphere), and it is waning (decreasing in illumination) toward the new moon. It is the final primary phase before the cycle repeats.
The term "last quarter" is used specifically in the context of astronomy, lunar calendars, and general descriptions of the Moon's appearance. * The last quarter moon is high in the sky at sunrise. * According to the calendar, the last quarter will occur on Friday. * After the full moon comes the waning gibbous, followed by the last quarter.
- As a time reference: Historically and in some calendars, the lunar phases, including the last quarter, are used to mark the passage of time within a month.
- The festival is traditionally held during the last quarter of the lunar month.
- Lunar phase / Moon phase (noun): Any of the cyclical shapes of the illuminated portion of the Moon as seen from Earth, including new, waxing crescent, first quarter, waxing gibbous, full, waning gibbous, last quarter, and waning crescent.
- Waning (adjective): Describing the period when the Moon's visible illuminated area is decreasing, from full moon to new moon. The last quarter occurs during the waning period.
- Third quarter: This is a direct synonym often used interchangeably in astronomy. Both "last quarter" and "third quarter" refer to the same lunar phase.
- First quarter: The opposing primary lunar phase where half of the Moon is illuminated (the right half in the Northern Hemisphere) and it is waxing (increasing in illumination).
- the last fourth of the Moon's period of revolution around the Earth