10 Fascinating Facts About the Summer Solstice

In 2024, June 20 marks the summer solstice, the first official day of astronomical summer.

“Solstice” means the sun has reached its highest point in the sky for the year; on Thursday, it will happen at 4:51 p.m. Eastern Daylight Time.

For those who want to pass the time during those extra hours of natural sunlight for reading, below TIME brings together some surprising facts about the summer solstice and its history.

The summer solstice is the longest day of the year

In New York City, for example, the sun will rise on Thursday at 5:24 am and set at 8:30 pm, meaning there will be 15 hours and 5 minutes of daylight. After that, the days will start to get shorter as we move towards winter.

…but only in the northern hemisphere

In the Southern Hemisphere, June 20 is the shortest day of the year. The Earth has seasons because it is tilted, so sunlight changes throughout the year differently for different parts of the world.

The 2024 summer solstice is the oldest since 1796

Typically, it’s a rule of thumb that the seasons begin on the 21st of the appropriate month, but that’s not always the case — and the precise timing of this year’s solstice is particularly early. The simplest reason is that 2024 is a leap year. Like Washington Publish explains“During leap years like 2024, the solstices and equinoxes occur about 18 hours and 11 minutes apart. earlier than the previous year.” During non-leap years, the timing of the solstice shifts later, so things generally even out over time.

No one knows who discovered the solstice

The question of who first discovered that the longest day of the year corresponds to the Sun’s highest point in the sky is “spectacularly unanswerable,” Owen Gingerich, professor emeritus of astronomy and the history of science at Harvard University, told TIME in 2016. “There is no writing to record this great discovery. Lost in the mists of time!”

See more information: Photographing the longest day of the year inside the Pantheon in Rome

But ‘Egyptian Stonehenge is the first indication people knew about the summer solstice

Around 6,000 to 6,500 years ago, nomadic herders from southern Egypt are believed to have laid out stones that align with the path of the solstice sun in the Nabta Playa basin, beneath the Tropic of Cancer. “[The solstice] it was an important touchstone that said, ‘Well, the Nile is about to enter its flood cycle,’ and that would basically kick off its calendar,” as NASA astronomer Sten Odenwald told TIME in 2016.

The summer solstice is a boon for solar energy

More sunlight per day means more energy for solar panels, increasing the supply of electricity in homes with the configuration. On social media, many solar energy companies will likely take advantage of the summer solstice to talk about the benefits of this clean energy solution.

The summer solstice is not the hottest day of the year

This year, the summer solstice corresponds with a record heat wave in many parts of the US, so check out TIME’s guide to staying safe. Still, like New York Times reportsIt takes some time for the Earth to warm up each summer, so the hottest temperatures of the year usually occur in July or August.

See more information: See summer solstice celebrations around the world

People are going to play a lot of golf…

Golf clubs across the country are holding golf tournaments from sunrise to sunset this week. For example, at Bandon Dunes in southern Oregon, golfers often adapt 72 holes golf course from sunrise to sunset.

…enjoying herring and vodka…

In Sweden, there are all kinds of parties celebrating the summer solstice, where people dance around a maypole with flowers in their hair, eat lots of smoked fish and drink shots. “Many children are born nine months after the summer solstice in Sweden,” Jan-Öjvind Swahn, a Swedish ethnologist, once said. counted CNN.

…And doing yoga

In India, mass yoga sessions take place, attracting hundreds of thousands of participants. As TIME previously reported, the summer solstice is said to be when Adiyogi, the first yogi, met his disciples. Historically, the United Nations has scheduled International Yoga Day for the summer solstice.