Moon phase
The moon between us and the sun, and invisible for it — the cycle at zero.
These are associations the community holds, not settled fact — the more a reading is shared, the bolder it sits.
Astronomically the new moon is an instant, not a night: the moment the moon and sun share the same ecliptic longitude, so the lit face is turned entirely away from us. For roughly a day either side it rises and sets with the sun and cannot be seen at all. Practitioners often use "dark moon" for the two or three nights around it, which is a useful working term rather than an astronomical one.
The cycle it opens averages 29.53 days — twenty-nine days, twelve hours and forty-four minutes — and wanders by several hours in either direction, because the moon's orbit is an ellipse and the sun keeps pulling on it. That is why lunar dates never sit still on a calendar, and why any almanac giving a fixed day of the month is rounding.
Practice at the new moon is nearly always about starting. Intentions written down, seeds set, the first move made while there is nothing to show for it yet. The one rule that carries across most lunar traditions is simply direction: build on the waxing, release on the waning. Everything else is decoration on that.
Readings practitioners have offered, ordered by how many recognise them. Take what serves, leave the rest.
Carried forward
Pliny the Elder, Natural History (c. 77)
Pliny’s farming books take the moon entirely seriously as a timetable — sow and graft while it waxes, cut timber and harvest while it wanes, and do certain jobs only on the darkest nights. He is reporting the practice of working farmers rather than arguing for it, which is why the passage has outlived his physics.
Carried forward
Common in contemporary practice
One intention per cycle, written at the new moon and read again at the full to see whether it survived contact with a fortnight. The check is the useful half.
Credit what you carry. Much of this comes from living traditions, and some of it from traditions that are closed — held by particular peoples and not offered for general use. Where you know whose practice a reading came from, name them; where you don't, say that too.