Last Quarter
Illumination: 50%|Phase angle: ~270°
Also called the Third Quarter, exactly half of the Moon's visible surface is illuminated — the left half in the Northern Hemisphere. The Moon rises around midnight and sets around noon. We are now three quarters of the way through the lunar cycle.
Orbital Geometry
The Moon is at 90° west of the Sun (western quadrature). The left half of the near side is illuminated. This is the mirror image of the first quarter phase.
Visibility & Observation
Rises around midnight, reaches its highest point at sunrise, and sets around noon. Like first quarter, the straight terminator reveals excellent crater detail along the terminator line.
Tidal Effects
Last quarter produces neap tides, as the Sun and Moon are again at right angles, resulting in the smallest difference between high and low tides.