At the same time, the Earth's axial tilt means we are getting a few seconds more daylight every day in the Southern Hemisphere in the lead up to summer solstice, but this has a small effect on the sunset and sunrise times compared with the much larger difference between solar time and clock time.
The earliest sunrise occurs before the Earth hits its speedy orbit during December. It is this effect that leads to the staggering of the earliest sunrise, the solstice and the latest sunset.
Just as a solar day isn't always exactly 24 hours, then a solar year is slightly longer than days — Watson says this irregularity prompted the invention of leap years to stop our calendars falling too far out of sync with the seasons. It's the addition of an extra day in February in a leap year which varies the date of the summer solstice. In — a leap year — the Southern Hemisphere summer solstice fell on the 21st December in Australia, but last year it was the 22nd December and it will also fall on the 22nd this year.
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Find out more Accept Cookies. Close cookie banner. One of the world's oldest evidence of the summer solstice's importance in culture is Stonehenge in England, a megalithic structure which clearly marks the moment of the June solstice. In the Southern Hemisphere, where the June solstice is known as the shortest day of the year, it marks the first day of astronomical winter, but the middle of winter in meteorological terms.
On the June solstice, the midnight sun is visible weather permitting throughout the night, in all areas from just south of the Arctic Circle to the North Pole. On the other side of the planet, south of the Antarctic Circle there's Polar Night, meaning no Sunlight at all, on the June solstice.
Even though most people consider June 21 as the date of the June solstice, it can happen anytime between June 20 and June 22, depending on which time zone you're in. June 22 solstices are rare - the last June 22 solstice in UTC time took place in and there won't be another one until After the solstice, it begins moving north again.
Since the Northern Hemisphere is tilted away from the Sun in December, it receives less sunlight during the course of a day. At the solstice, the North Pole's tilt away from the Sun is greatest, so this event marks the shortest day of the year north of the equator. This effect is greatest in locations that are farther away from the equator.
In tropical areas, the shortest day is just a little shorter than 12 hours; in the temperate zone, it is significantly shorter; and places within the Arctic Circle experience polar night , when the Sun does not rise at all. Conversely, the day of the December solstice is the longest day of the year in the Southern Hemisphere. Here, too, the effect is greater the farther a location is away from the equator.
Sun times at the South Pole in December. During the course of a year, the subsolar point—the spot on the Earth's surface directly beneath the Sun—slowly moves along a north-south axis.
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