solstices

The two points on the ecliptic where the Sun reaches its maximum and minimum declination, or the times at which the Sun is at these points. They lie approximately midway between the vernal and autumnal equinoxes. The solstices occur on about 21 June and 21 December. At the summer solstice, the Sun reaches its highest altitude in the sky and the duration of daylight is a maximum. At the winter solstice the Sun's altitude at noon is the lowest as seen from a particular latitude, and the duration of daylight is a minimum. The summer solstice in the northern hemisphere (June) is the winter solstice in the southern hemisphere and vice versa.