Last Quarter Moon: Half Disc and Morning Moon
The short answer: last quarter is the phase when the left half of the disc is lit (Northern Hemisphere). The Moon rises around midnight and is visible in the morning — about three quarters of the way from new moon.
Last quarter closes the cycle of lit phases: after it comes only the fading crescent and the next new moon. This is the "morning" Moon, seen by early birds rather than night owls.
Geometry of last quarter
The Moon is about three quarters through the synodic cycle from new moon: its ecliptic longitude is about 90° west of the Sun. The left half of the disc is visible (Northern Hemisphere), while the right stays in shadow.
Astronomical age is about 22.1 days and illumination is near 50% at the quarter instant, then shrinks daily toward crescent. On lunar.day the day card shows the lunar-day number, not astronomical age.
Schedule: the morning Moon
| Event | Time (approx.) |
|---|---|
| Moonrise | Around midnight |
| Culmination | At dawn, high in the south |
| Moonset | Around noon |
No Moon in the evening — the sky is dark right after sunset. Convenient for observing in the first half of the night. Toward morning the Moon climbs and shines until noon, paling in the daylight sky.
Mirror of first quarter
| Parameter | First quarter | Last quarter |
|---|---|---|
| Astronomical age | ~7.4 days | ~22.1 days |
| Lit | ~50%, right side | ~50%, left side |
| Trend | Growing to full moon | Shrinking to new moon |
| Visibility | Day + evening | Night + morning |
| Rise / set | Noon / midnight | Midnight / noon |
Easy to remember: quarters are opposites in everything except the percentage.
Terminator at work again
Like the first one, last quarter puts the terminator across the disc centre — long shadows, excellent crater relief. The only difference is the lit side: now the left side of the visible disc is lit, while the right side was lit at first quarter.
Waning crescent: the finale
After last quarter the lit share melts away: the waning crescent grows thinner and rises later until it merges with dawn 1–2 days before new moon. The cycle closes.
How to follow quarters on lunar.day
The moon/phase/[date] page shows values for the selected day. Check illumination near 50% and moonrise around midnight — signatures of last quarter.
Summing up
Last quarter is about 50%, left half, a night-and-morning waning Moon. The mirror of first quarter and the final milestone before new moon.
Related articles
What Is the Moon Phase Cycle
The short answer: moon phases are how much of the Sun-lit half of the Moon we see from Earth. The full cycle (synodic month) lasts 29.53 days: from new moon through first quarter and full moon to last quarter.
First Quarter Moon: Half Disc and Evening Moon
The short answer: first quarter is the phase when the right half of the disc is lit (Northern Hemisphere). The Moon is visible in the evening and sets around midnight — about one quarter of the way from new to full moon.
Moon Illumination, Age and Distance: What the Numbers Mean
The short answer: illumination is the share of the visible disc lit by the Sun (0–100%); astronomical age is the time since new moon; distance is the kilometres to the Moon. These are different measures: they help describe the phase, position in the cycle and apparent size, but do not fully determine observing conditions.