The date of the beginning of summer varies according to climate, tradition and culture, but when it is summer in the Northern Hemisphere, it is winter in the Southern Hemisphere, and vice versa.
In the Northern Hemisphere summer lasts from the Summer Solstice (about 21 June) to the Autumnal Equinox (September 22 or 23). In the Southern Hemisphere, summer lasts from December until March.
At the summer solstice, the days are longest and the nights are shortest, with day-length decreasing as the season progresses after the solstice.
The 1st day of summer 2017 in Northern Hemisphere will be on Wednesday, 21st June. And the last day of summer 2017 will be on Friday 22nd September.
The reason the equinoxes and solstices don’t always come on the same day is that Earth doesn’t circle the sun in exactly 365 days.
Solstices happen twice a year – in June and December .
One might think that since it is summer in the Northern Hemisphere, the Earth is closest to the Sun during the June Solstice. But it’s the opposite – the Earth is actually farthest from the Sun during this time of the year. In fact, the Earth will be on its Aphelion (the point in the orbit of a planet, asteroid, or comet at which it is furthest from the sun) a few weeks after the June Solstice.
The Earth’s orbit around the Sun has very little effect over the Seasons on Earth. Instead, it the tilt of Earth’s rotational axis, which is angled at around 23.4 degrees, that creates seasons.
The direction of Earth’s tilt does not change as the Earth orbits the Sun – the two hemispheres point towards the same direction in space at all times. What changes as the Earth orbits around the Sun is the position of the hemispheres in relation to the Sun – the Northern Hemisphere faces towards the Sun during the June Solstice, thus experiencing summer. The Southern Hemisphere tilts away from the Sun and therefore enjoys winter during this time.
“Summer” came from the Old English name for that time of year, sumor. This, in turn, came from the Proto-Germanic sumur-, which itself came from the Proto-Indo-European root sam- (sam- seems to be a variant of the Proto-Indo-European sem-, meaning “together / one”).
Solstice comes from the Latin words sol, meaning ‘Sun’ and sistere, meaning ‘to come to a stop or stand still‘.
The “dog days of summer” refer to the weeks between July 3 and August 11 and are named after the Dog Star (Sirius) in the Canis Major constellation. The ancient Greeks blamed Sirius for the hot temperatures, drought, discomfort, and sickness that occurred during the summer.
The month of June was named after either Juniores, the lower branch of the roman Senate, or Juno, the wife of Jupiter.
Marc Antony named the month of July, in honor of Julius Caesar.
The month of August was named for Julius Caeser’s adopted nephew Gaius Julius Caesar Octavius, who held the title “Augustus.” He named the month after himself.
“September” is from the Latin word septem, meaning “seven.”
The word “season” in this context comes from the Old French “seison”, meaning “sowing / planting”. This in turn came from the Latin “sationem” meaning “sowing”.
Ancient pagans celebrated midsummer with bonfires. It was believed that the crops would grow as high as a couple could jump across the fire. Additionally, bonfires would generate magic by boosting the sun’s powers.
Many ancient civilizations celebrated the summer solstice. For example, the ancient Greeks celebrated the agriculture god Cronus; the ancient Romans paid tribute to Vesta, the goddess of the hearth; and the ancient Chinese honored femininity and the force known as yin.
In southern England, more than 35,000 people gather at Stonehenge to see the summer solstice. Druids and pagans are among those who celebrate the longest day of the year at this notable place.
The Eiffel Tower grows in summer. This historic structure is made of iron. Metal expands with heat. As a result, the Eiffel Tower can grow more than 15 centimeters (6 inches) in hot weather.
The first Olympic Games in the modern era were the 1896 Summer Olympics, officially known as the Games of the I Olympiad in Athens, Greece. The Games featured the Panathinaiko Stadium, the first giant stadium of the modern world that housed the largest crowd to ever watch a sporting event.
Shakespeare’s Midsummer Nights Dream takes place on Midsummer’s Eve, a time that Elizabethans would have associated with celebration. The summer solstice was associated with dancing drinking, mystery, and magic. In his bewitching play, Shakespeare captures the festive atmosphere of the season and even includes some summer rituals.
In Chinese astronomy, summer starts on or around 5 May, with the jiéqì (solar term) known as lìxià, i.e. “establishment of summer”, and it ends on or around 6 August.
According to meteorologists, summer extends for the whole months of June, July, and August in the northern hemisphere and the whole months of December, January, and February in the southern hemisphere. Under meteorological definitions, all seasons are arbitrarily set to start at the beginning of a calendar month and end at the end of a month.
Summer is the by far the busiest time at movie theaters, and Hollywood always hopes to earn a significant portion of total annual ticket sales through summer blockbuster months.