( CNN ) -- Here is a look at what you need to know about the solstice . Summer solstice will take place on June 21 , 2013 . Summer solstice in the Northern Hemisphere occurs on June 20 , 21 , or 22 , when the sun reaches its most northerly point , directly overhead at the Tropic of Cancer ( 23 degrees 27 minutes north latitude ) . The summer solstice is the longest day of the year and marks the beginning of summer . Winter solstice in the Northern Hemisphere occurs on December 21 or 22 , when the sun appears at its most southerly position , directly overhead at the Tropic of Capricorn ( 23 degrees 27 minutes south latitude ) . The winter solstice is the shortest day of the year and marks the beginning of winter . It is the exact opposite in the Southern Hemisphere . A solstice is different from an equinox , the two times each year when the sun is directly above the Earth 's equator and day and night are of equal length . Equinoxes mark the beginning of spring ( March ) and fall ( September ) . Solstice loosely translated in Latin is `` sun stands still '' . For several days before and after each solstice the sun appears to stand still in the sky , i.e. , its noontime elevation does not seem to change from day to day . Historically , the solstice has been celebrated by numerous cultures around the world . Thousands of people annually celebrate the summer solstice at Stonehenge in Wiltshire , England . At sunrise at Stonehenge on the longest day of the year , the rising sun appears behind one of the main stones , creating the illusion that the sun is balancing on the stone . The site was closed for 16 years after rioting broke out between police and revelers for several years at solstice gatherings . Stonehenge was re-opened to the public on Solstice in 2000 .
The event happens twice each year when the Earth is at either its northernmost or southernmost point . Summer solstice will occur on June 21 , 2013 at midnight UT in the Northern Hemisphere . Winter solstice will take place on December 21 , 2013 at 5:11pm UT in the Northern Hemisphere .