Sunshine abounds as the summer solstice arrives

Peak sunshine has arrived in the Northern Hemisphere — the summer solstice.
Friday is the longest day of the year north of the equator, where the solstice marks the start of astronomical summer. It's the opposite in the Southern Hemisphere, where it is the shortest day of the year and winter will start.
The word 'solstice' comes from the Latin words 'sol' for sun and 'stitium' which can mean 'pause' or 'stop.' The solstice is the end of the sun's annual march higher in the sky, when it makes its longest, highest arc. The bad news for sun lovers: It then starts retreating and days will get a little shorter every day until late December.
People have marked solstices for eons with celebrations and monuments, including Stonehenge, which was designed to align with the sun's paths at the solstices. But what is happening in the heavens? Here's what to know about the Earth's orbit.
As the Earth travels around the sun, it does so at an angle relative to the sun. For most of the year, the Earth's axis is tilted either toward or away from the sun. That means the sun's warmth and light fall unequally on the northern and southern halves of the planet.
The solstices mark the times during the year when this tilt is at its most extreme, and days and nights are at their most unequal.
During the Northern Hemisphere's summer solstice, the upper half of the earth is tilted toward the sun, creating the longest day and shortest night of the year. This solstice falls between June 20 and 22.
Meanwhile, at the winter solstice, the Northern Hemisphere is leaning away from the sun — leading to the shortest day and longest night of the year. The winter solstice falls between December 20 and 23.
The equinox is when there is an equal amount of day and night
During the equinox, the Earth's axis and its orbit line up so that both hemispheres get an equal amount of sunlight.
The word equinox comes from two Latin words meaning equal and night. That's because on the equinox, day and night last almost the same amount of time — though one may get a few extra minutes, depending on where you are on the planet.
The Northern Hemisphere's spring — or vernal — equinox can land between March 19 and 21, depending on the year. Its fall – or autumnal — equinox can land between Sept. 21 and 24.
On the equator, the sun will be directly overhead at noon. Equinoxes are the only time when both the north and south poles are lit by sunshine at the same time.
What's the difference between meteorological and astronomical seasons?
These are just two different ways to carve up the year.
While astronomical seasons depend on how the Earth moves around the sun, meteorological seasons are defined by the weather. They break down the year into three-month seasons based on annual temperature cycles. By that calendar, spring starts on March 1, summer on June 1, fall on Sept. 1 and winter on Dec. 1.
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The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institute's Department of Science Education and the Robert Wood Johnson Foundation. The AP is solely responsible for all content.

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Watch a Met Office video explaining the summer solstice - When is the summer solstice? Sign up to our daily newsletter – Regular news stories and round-ups from around Scotland direct to your inbox Sign up Thank you for signing up! Did you know with a Digital Subscription to The Scotsman, you can get unlimited access to the website including our premium content, as well as benefiting from fewer ads, loyalty rewards and much more. Learn More Sorry, there seem to be some issues. Please try again later. Submitting... The Met Office says the summer solstice occurs when the northern hemisphere is fully tilted towards the Sun. It is the longest day and shortest night of the year. Here's all you need to know about the summer solstice, including when the summer solstice is this year, why the date changes and what the weather forecast is. Advertisement Hide Ad Advertisement Hide Ad Daniel Leal / AFP via Getty Images | Daniel Leal / AFP via Getty Images Is the summer solstice the start of summer? Meteorological summer began on June 1, and will end on August 31, as it does every year. However, the summer solstice is the start of astronomical summer, which will end on September 22 this year. When is the summer solstice? The summer solstice occurs on June 21 or June 22 each year. This year the summer solstice will be on June 21. Why does the date of the summer solstice change? According to the BBC, the exact date of the summer solstice changes slightly each year due to the calendar year not perfectly matching the time it takes for the Earth to orbit the Sun. Advertisement Hide Ad Advertisement Hide Ad Is the summer solstice the latest sunset of the year? The summer solstice is the day with the most hours of daylight in the year, but it's not the latest sunset or the earliest sunrise. The earliest sunrises take place before the summer solstice, and the latest sunsets happen after. Is the summer solstice celebrated? Many people in the UK celebrate the summer solstice at Stonehenge. Stonehenge was built to align with the sun on the solstices. This year summer solstice will be celebrated at Stonehenge from 7pm on June 20 to 8am on June 21. Advertisement Hide Ad Advertisement Hide Ad There will also be a solstice swim in Bridlington. The Flamborough Flippers are inviting people to join them for a swim in the sea, and ask people to try and be in the water at Bridlington's North Beach by 04:42 on June 21. In Scotland, Jupiter Artland in Edinburgh is running a summer solstice celebration evening, with activities such as sound baths, sunset swims and flower crown building. To find out more and to book tickets visit their website here . What is the forecast for the summer solstice? The Met Office UK weather forecast for summer solstice this year - June 21 - is: 'Hot and humid with sunny spells. Thundery showers moving north and east through the day, heaviest over northern England and Wales. Turning fresher from the west later.'