Winter Solstice: The shortest day of the year has arrived
Today marks the winter solstice, which will see the Northern Hemisphere experience its shortest day of the year.
The phenomenon may bring the most darkness we've experienced all year round - but starting on Sunday, days will get lighter and longer every day until June.
At around December 21 each year, the sun will be at its most southerly point, directly overhead at the Tropic of Capricorn - an imaginary line of latitude which passes through southern Africa, Australia and South America.
Whilst the Northern Hemisphere will experience its shortest day, the Southern Hemisphere will have its longest day of the year.
Monuments such as Stonehenge and the Torreon at Peru's Machu Picchu were designed in part to align with solstices.
What is the solstice?
The Earth's tilt is what gives us different seasons, and means the Northern and Southern Hemispheres experience winter and summer at opposite times.
Each hemisphere experiences winter when it is angled away from the sun, and moves into summer when it tilts towards the sun.
The solstices mark the times during the year when the Earth is at its most extreme tilt toward or away from the sun.
Scientists don't know exactly why our planet became tilted on its axis, but some theories suggest it was knocked off balance by a huge collision.
During the Northern Hemisphere’s winter solstice, the upper half of the Earth is tilted away from the sun, creating the shortest day and longest night of the year. The winter solstice falls between December 20 and 23.
Meanwhile, at the summer solstice, the Northern Hemisphere is toward the sun, leading to the longest day and shortest night of the year. This solstice falls between June 20 and 22.
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How short will the day be?
The shortest day lasts seven hours 49 minutes and 42 seconds in London.
This means that the length of the day during the winter solstice is eight hours – 49 minutes shorter than the summer solstice.
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