Lunar eclipse

The Moon passes through the Earth’s shadow, at full Moon. It can be penumbral (barely visible), partial or total; during totality the Moon turns coppery red, lit by light filtered through all the Earth’s sunsets. It is perfectly safe to watch with the naked eye.

ToolsThe Moon tonight

Related terms

Solar eclipse: The Moon passes in front of the Sun, at new Moon. It is total if the Moon hides it completely, annular if the Moon is too far to cover it (a ring stays visible), partial elsewhere. Never look at the Sun without certified eclipse glasses, except during the brief total phase.
Moon phases: The Moon’s changing look depending on how much of its sunlit side we see: new Moon, crescent, first quarter, gibbous, full Moon, then back again. The full cycle, the lunation, lasts 29.5 days. For relief, prefer the quarters to the full Moon, which looks flat.

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