Do you yearn for long days and short nights? Then this could be the best day of the year for you and fellow sunlight seekers.

The summer solstice is Wednesday, June 21. It’s the longest day and shortest night in the Northern Hemisphere. It’s also the first official day of summer.

Our ancient ancestors certainly took note of the yearly occasion. Some of their monuments were aligned to precisely mark the summer solstice light (looking at you Stonehenge).

Pagan celebrations of the day carry on into modern times. Today’s events include gatherings at Stonehenge in England, the Midsummer Eve celebration in Sweden and Ivan Kupala Night in parts of Eastern Europe.

The solstice is historically linked to fertility – both the plant and human variety – in destinations worldwide.

The science of the solstice and its traditions have fascinated people for millennia.

Summer solstice science

Is summer solstice all over the world? No. It’s only in the Northern Hemisphere, where almost 90% of the world’s population lives. People south of the equator in places such as Chile, South Africa and Australia are having their winter solstice and the shortest day of the year there.

When is the 2023 summer solstice exactly? It will fall at 14:58 UTC (Universal Time Coordinated) on June 21. Your time zone in relation to UTC determines the time and even the date that the solstice happens for you. For instance, that’s 7:58 a.m. in Los Angeles, 10:57 a.m. in New York City, 3:57 p.m. in London and 11:57 p.m. in Tokyo. Earthsky.org has a handy time zone conversion tool.

Who gets the most sunlight? The differences in how much daylight you get become very dramatic as you get closer to the poles and farther from the equator. In Ecuador’s capital Quito, barely north of the equator, people barely notice the difference. They get a measly extra six and a half minutes of daylight.

But residents of northerly Helsinki, Finland, will get a 3:54 a.m. sunrise and almost 19 hours of daylight. Even the night doesn’t get that dark. The denizens of Fairbanks in central interior Alaska can scoff at those 19 hours. They’ll get almost 22 hours of daylight, and blackout curtains might be in order.

Why don’t we just get 12 hours of daylight all year? Folks all over the planet actually did get nearly equal doses of day and night back during the spring equinox. But the amount of sunlight in the Northern Hemisphere has been increasing daily ever since. That’s because the Earth is aligned on an axis, an imaginary pole going through the center of our planet. But this axis tilts – at an angle of 23.5 degrees.

“As Earth orbits the sun [once each year], its tilted axis always points in the same direction. So, throughout the year, different parts of Earth get the sun’s direct rays,” explains NASA. When the sun reaches its apex in the Northern Hemisphere, that’s the summer solstice.

Is this also the hottest time of year? Generally, it’s not. “On average, the vast majority of the United States experiences its warmest temperatures in July or early August,” says CNN Senior Weather Producer Taylor Ward.

“Temperatures essentially continue to rise after the summer solstice because the amount of energy coming in from the sun continues to be greater than the amount of energy lost at night – so it is basically an accumulation of warmth until the daylight gets short enough that this changes,” says Ward. “The only area of the country that actually sees their warmest temperatures in June, coinciding with the longest daylight of the year, is portions of the Southwest” because of the timing of the cloudy monsoon season there in July and August.

The same general temperature pattern holds true in places such as Japan and much of Europe.

How to celebrate summer solstice

What does Stonehenge have to do with the summer solstice? The ancient stones of the monument in Southwest England dating to around 2500 BC were aligned by its makers astronomically.

The central axis of Stonehenge was aligned with the sunrise at the summer solstice and sunset at the winter solstice so that the stones precisely frame the rising and setting sun when days were at their longest and shortest. And it still works like clockwork in modern times.

The English Heritage Society organizes gatherings at Stonehenge for the summer solstice and produces a live stream of the sunrise.

What other cultural traditions surround the summer solstice? In Sweden, the Midsummer Eve celebration is tied to the solstice, always being held on a Friday that lands anywhere from June 19 to June 25. Maypoles, folk dancing and romantic rituals are the order of the day.

In Ukraine and some other places in Eastern Europe, the summer solstice is connected with Ivan Kupala Night – a holiday with romantic connotations for many Slavs. People dance, place flowered wreaths on the water and gather around bonfires.

In India, the birthplace of the ancient practice of yoga, the summer solstice is traditionally celebrated with mass yoga sessions throughout the nation. And the United Nations’ International Yoga Day falls each year on the summer solstice.

Bring on the cookouts, bust out the outdoor games, and start filling up those pools — summer is just about here! Though temps have been steadily rising across the country for weeks now, you may be surprised to know that the season of fresh watermelon, breezy beach reads and long weekend getaways to quaint small towns doesn’t officially kick off until just about halfway through the year. So when is the first day of summer, exactly? Read on for everything to know about kicking off the season right, including the celestial matters that dictate the transition from spring. When is the first day of summer?In the northern hemisphere this year, the first day of summer is Sunday, June 20, 2021. What determines the first day of summer? The first day of summer is determined by the tilt of the earth's axis as it rotates around the sun. The day that the North Pole is pointed closest to the sun, the northern hemisphere receives the most light for the longest amount of time. This day is known as the June or summer solstice, with a solstice being the twice-yearly astronomical occurrence when the sun is the greatest distance from Earth’s equator. (If you’re in the northern hemisphere, that means the sun will sit at its highest point in the sky during the summer solstice; during the winter solstice, it will sit at its lowest.) As the 24-hour period with the longest "day" and shortest "night" in the 365-day calendar year, the day of the summer solstice marks the first day of the summer season. If you want to get really technical, the exact time of the summer solstice this year is 11:32 p.m. ET.Is it the same day every year? Not exactly, and that is due to how long it technically takes the earth to complete one rotation around the sun. The Gregorian calendar, which is the international standard used for societal and scientific purposes, marks this passage of time — one year — as 365 days. But a solar year is actually closer to 365 days and six hours. This discrepancy gives us Leap Day every four years, and it also bumps the summer solstice a day or two depending on the year. The first day of summer will always fall on or between June 20 and June 22. When does summer end? In the northern hemisphere, the September or autumn equinox marks the end of summer and the beginning of fall. An astrological equinox, which occurs twice yearly, is the date when the sun passes over the equator, and from the northern hemisphere to the southern hemisphere. (On this date, day and night will be of equal length.) After the autumn equinox, the North Pole begins to tilt away from the sun, which begins a season of longer nights and shorter days. This year, the autumn equinox is Wednesday, Sept. 22, 2021. That means you’ve got 94 days to make the most of summer this year.