Fact #009
Observing
Point binoculars at the line between light and dark. That's where the Moon stops being a disc and becomes a landscape.
Along the terminator the Sun sits near the lunar horizon, so crater rims cast long shadows and mountain peaks catch light while the valleys beside them stay black. A pair of 10x50 binoculars braced against a wall is genuinely enough. No telescope required.
Source: NASA Moon observing (opens in a new tab) · checked Aug 2026
🔮 The folklore version: The first quarter is the argument