The longest day of the year invites endless possibility. But this moment of peak illumination also marks the beginning of the sun's retreat. "CBS Evening News" co-anchor John Dickerson has more.

On the first day of summer, North Texans gathered at a local water park to enjoy the heat, sunshine, and extra daylight.

Once a year, an astronomical alignment ushers in this seasonal change. Like its winter counterpart, the summer solstice is celebrated across the world—and shrouded in myth.