The third full moon in a season of four full moons.
The giant planet will be at its closest approach to Earth and its face will be fully illuminated by the Sun. It will be brighter than any other time of the year and will be visible all night long. This is the best time to view and photograph Jupiter and its moons. A medium-sized telescope should be able to show you some of the details in Jupiter’s cloud bands. A good pair of binoculars should allow you to see Jupiter’s four largest moons, appearing as bright dots on either side of the planet
In the northern hemisphere, the longest day of the year when the Sun is farthest north. The summer solstice marks the first day of the season of summer. In the southern hemisphere, this is your winter solstice, marking the shortest day of the year. The declination of the Sun on the (northern) summer solstice is known as the tropic of cancer (23° 27′).
http://scienceworld.wolfram.com/astronomy/SummerSolstice.html