Quarter phase - The phase of the moon in which half of the near side of the Moon is illuminated by the Sun
Quasar - A distant galaxy, seen as it was in the remote past, with a very small, luminous nucleus ...
It occurs at first and third quarter phase, when the Moon's tidal effect is perpendicular with the Sun's tidal effect.
The quadrature locations are sort of like the quarter phases of the Moon, at least in terms of the questions of "when do they rise," "when do they set," etc.
Conversely, when the Moon is at first quarter or last quarter phase (meaning that it is located at right angles to the Earth-Sun line), the Sun and Moon interfere with each other in producing tidal bulges and tides are generally weaker; ...
A major (or minor) lunar standstill always happens near an equinox; and what's more, it happens when the Moon is at or near quarter phase.
Last Quarter As last quarter phase - when the Moon enters the last quarter of its orbit back to new moon - the eastern (left) half of its disk is illuminated.
Mercury is brightest as seen from Earth when it is at a gibbous phase, between either quarter phase and full.
At its brightest ("full moon") it would be about as bright as Venus is from Earth; at the first or third quarter phase it would be about as bright as Vega. When Deimos passes in front of the Sun its angular diameter is only about 2.
When the Moon is in a quarter phase, its brightness is not half of a full moon, but only about a tenth. This is because the lunar surface is not a perfect Lambertian reflector.
After the first quarter phase, more than a quarter of the Moon is visible to us, so it is now in a "waxing gibbous" phase. As the Moon continues its revolution around Earth, the Sun, Earth, and Moon align with the Earth in the middle.
gibbous phase
The collective term given to the lunar phases between the quarter phases and full moon. A gibbous moon is illuminated by more than 50%.
The Last Quarter Moon rises at midnight, transits the meridian at sunrise and sets at noon. The Last Quarter phase repeats every 29.531 days - one synodic month.
information, we can see how any moon visible just before evening has to be in the east, and be a first quarter moon, or close to it. By the same logic, any moon visible in the early morning hours has to be in the west, and be in third quarter phase, ...
Quadrature. The position of the Moon or another planet when it is at right angles to the Sun as seen from Earth. An example would be when the Moon is seen at First or Last Quarter phases.
 See also: Phase, Earth, Moon, Sun, Orbit
  
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