Today is the longest day of the year. The summer solstice is today. The sun rose at 5:40 a.m. and sets at 8:52 p.m., for a total of 15 hours and 12 minutes of daylight. This is the day the sun shines directly over the Tropic of Cancer due to the Earth’s tilt. The Tropic of Cancer runs through Mexico, China and India in the Northern Hemisphere. Today is also the official start of summer.