Video narration
Why does the Moon seem to show up about 50 minutes later each day? Imagine walking with a friend who keeps moving ahead. To keep them in view, you have to turn a little farther. The thing you're watching has moved too. Earth turns roughly once every 24 hours, while the Moon moves eastward along its orbit. After Earth turns all the way around, the Moon isn't back in the same direction. Earth must turn a little longer-about 50 minutes on average-to line up again. But 24 hours and 50 minutes isn't the Moon's orbit. It takes about 27.3 days to go around Earth. The extra time is Earth's turn toward a Moon that's moved on. Like keeping your walking friend in view, Earth turns a little farther to bring the moving Moon back to the same spot in our sky.