The half of Earth that can see the Moon right now, and the one point where it stands directly overhead. If your city is inside the lit region, the Moon is above your horizon — whether or not the Sun is too.
The Moon is above the horizon for roughly half the planet at any moment, and the lit region on the map is exactly that half. It has nothing to do with whether it is dark where you are: the Moon is up in broad daylight about as often as it is up at night, which is why you so often catch a pale daytime Moon and think it looks out of place. It isn’t — you are simply inside the lit region while the Sun is up too.
Just as with the Sun, there is one place where the Moon stands at the zenith — the sublunar point, marked in pale blue. It sweeps west a little slower than the Sun’s does, because the Moon is itself moving east along its orbit as Earth turns beneath it. That lag is why moonrise comes roughly 50 minutes later each night.
On 18 July 2026 the Moon is about 23% lit (waxing crescent). Phase is a global fact — everyone who can see the Moon sees the same fraction lit at the same moment — so it belongs here rather than on a per-city page. Where the Moon sits in your sky is local, and that lives on the Moon Phase pages.
The map answers one question honestly: is the Moon above your horizon? It does not promise a view. A thin crescent near the horizon in a bright twilight is often invisible to the eye, and cloud settles the matter regardless. For whether tonight is actually worth going outside for, the stargazing conditions page folds in live cloud cover and the Moon’s own glare.
The sublunar point is computed from a low-precision lunar series — good, but not exact. Checked against JPL Horizons (DE441) at 14 instants across a year, the worst disagreement was 0.38°, about 42 km on the ground. That is well inside the Moon’s own apparent width in the sky, and invisible at any zoom this map offers — but it is why the coordinate is shown to one decimal place and never to the second. Checked 2026-07-17. The ephemeris is used to test this page, never to feed it: nothing here is fetched at runtime, so the map keeps working with no network and no key.