Phase 01
New Moon
The Moon sits between Earth and the Sun, its lit side turned entirely away from us. It rises and sets with the Sun and is essentially invisible in the sky — the dark starting point from which every cycle begins.
Over roughly 29.5 days, sunlight sweeps across the Moon's face and back again. These are the eight phases of that quiet, endless journey.
The Moon makes no light of its own — it simply reflects the Sun. As it orbits Earth, we see different amounts of its sunlit half. That shifting geometry produces the familiar rhythm of waxing (growing) and waning (shrinking) light known as the lunar cycle, or lunation.
The Moon sits between Earth and the Sun, its lit side turned entirely away from us. It rises and sets with the Sun and is essentially invisible in the sky — the dark starting point from which every cycle begins.
A slender curve of light appears on the Moon's right edge and grows a little each night. Look for it low in the west just after sunset — often accompanied by the faint glow of "earthshine" on its shadowed part.
Exactly half the disc — the right side — is now lit. Despite the name, this is one week into the cycle: the Moon has completed a quarter of its orbit. It rides high at sunset and sets around midnight.
More than half of the Moon now glows, swelling toward full. "Gibbous" means humped or bulging. Rising in the afternoon and bright well into the night, it's a rewarding time to watch craters sharpen along the terminator.
Earth now lies between the Sun and the Moon, so the entire face we see is bathed in sunlight. It rises at sunset, shines all night, and sets at dawn — the brilliant midpoint and turning of the cycle.
Past full, the light begins to retreat — now fading from the right, leaving the left side bright. The Moon rises later each evening, often greeting early risers as a luminous shape still hanging in the morning sky.
Half the disc is lit again, but now it's the left side. Three quarters of the way around its orbit, the Moon rises near midnight and stands high at dawn — a fine sight for the early morning.
The last thin arc of light lingers on the left before dawn, dwindling night by night. Sometimes called the "old moon," it's the cycle's quiet farewell — soon the Moon will vanish into a new New Moon and begin again.