Summer officially arrives with the earliest solstice in more than 2 centuries

The sun rises complete Florida connected Thursday morning, hours up of nan presence of nan summertime solstice successful nan Northern Hemisphere. (Malcolm Denmark/FloridaToday/USA Today Network)

Summer officially arrives successful nan Northern Hemisphere connected Thursday, nan earliest commencement to nan play successful complete 2 centuries.

The summertime solstice — nan nonstop infinitesimal erstwhile Earth’s northbound rod is astir tilted towards nan sun — happens astatine 4:51 p.m. ET, according to the National Weather Service.

The arena marks nan longest time of nan twelvemonth (though nan nonstop number of daylight hours varies by location) and nan opening of astronomical summer. Meteorological summer, successful contrast, officially started connected June 1 — nan logic why millions of Americans were already under extreme power advisories in nan hours starring up to nan solstice.

The timing of nan summertime solstice people fluctuates betwixt June 20 and 22. But it’s an particularly large woody this year, arsenic it hasn’t happened this early since 1796.

That summertime solstice happened connected June 20 astatine 1:24 p.m. “Local Mean Time,” according to The Weather Network. It says LMT — utilized earlier nan U.S. introduced modular time in nan precocious 19th period — is adjacent capable to ET that nan comparison is valid.

At that point, George Washington was president of nan U.S., which Tennessee had conscionable joined arsenic nan 16th state.

What explains nan solstice’s extra-prompt arrival, these 228 years later?

The shortest reply is quirks successful nan calendar.

A emblematic twelvemonth has 365 days, but that’s not precisely really agelong nan Earth takes to orbit nan sun — it’s much for illustration 365.24. To relationship for that other quarter, nan Gregorian almanac adds a time to February each 4 years: leap day.

The measurement nan mathematics works, solstices (and equinoxes) drift about 45 minutes earlier every 4 years. By nan 2060s, leap twelvemonth solstices will beryllium earlier than thing successful nan 1700s, astrophysicist Ethan Siegel writes in Big Think.

That shape is owed to proceed until 2096, which will spot the earliest solstice of nan period astatine 2:32 a.m. ET connected June 20.

“It will beryllium nan only summertime solstice that group successful nan Pacific clip area of nan Americas will acquisition connected June 19 for respective hundreds of years!” Seigel adds.

Then, nan almanac will reset. That’s because 2100 won’t beryllium a leap year, since it’s 1 of those nosy Gregorian exceptions that are divisible by 100 but not 400.

In nan meantime, you don’t person to travel to Stonehenge or dance astir a maypole to make nan astir of nan summertime solstice.

Among different ideas, you tin look for the smallest shadows of nan year, jump on fast-food freebies, refresh yourself connected tips for staying safe successful nan heat and get fresh to regard astatine the Strawberry Moon, which will scope highest illumination successful nan U.S. conscionable aft 9 p.m. ET connected Friday.