The summer solstice (or estival solstice), also known as midsummer, occurs when a planet's rotational axis, in either northern or southern hemispheres, is most inclined toward the star that it orbits. Earth's maximum axial tilt toward the Sun is 23° 26′. This happens twice each year (once in each hemisphere), at which times the Sun reaches its highest position in the sky as seen from the north or the south pole.