Follow your curiosity

What discovery has been shared with you?

FACTREE gives you something interesting to discover every day — and something worth talking about together.

Start with one fact. Explore it, go deeper, then follow whichever branch catches your imagination.

Choose subjects for a surprise

Exploring any topic

Begin your discovery

Your next discovery is one click away.

Choose one or more subjects above, or leave Any Topic selected and let curiosity decide.

Astronomy

Solar and Lunar Eclipses: Alignment of Earth, Moon, and Sun

Quick fact

A solar eclipse can only occur during a new moon, and a lunar eclipse only during a full moon. Yet they don't happen every month because the Moon's orbit is tilted about 5 degrees relative to Earth's orbit around the Sun.

Why this is interesting

Have you ever seen the sky darken in the middle of the day? That's a solar eclipse—a cosmic alignment that turns day into twilight for a few minutes.