Washington Was President Last Time the Solstice Came So Early

What does everyone in the Northern Hemisphere have in common on Thursday? We're all marking the longest day of the year, aka the summer solstice, which officially takes place at 4:51pm ET when the sun reaches its highest annual point in the sky, as the Earth's axis is tilted most toward our fiery mother star, according to the National Weather Service. The New York Times dubs it "the scientific start of summer," or astronomical summer (meteorological summer started on June 1). After that, it's a slow jog toward the shortest day of the year—the winter solstice, taking place on Dec. 21. It's a slightly unique year for this seasonal situation. More:

• Early bird: USA Today notes that this year's summer solstice is the earliest since 1796, when George Washington was president. When it takes place each year depends on the "complex dance" between our planet's orbit around the sun and its day-to-day rotation, as well as Gregorian calendar "quirks" that will see the solstice pop up earlier than usual each leap year through 2100.

• The heat is on: Yes, much of the US has been experiencing a recent heat wave, but that doesn't mean the longest day of the year is traditionally the hottest. USA Today notes there's usually, on average, "a one-month lag between the solstice and peak summer temperatures"—meaning look out for July.
• How much daylight you'll see: Space.com offers a handy calculator so you can check out what to expect in your neck of the woods.
• Primers: The AP and BBC have more on what you need to know on everything solstice and equinox.
• Other 'fascinating facts': Time has 10 of them, including the "spectacularly unanswerable" question of who first stumbled upon the concept of the summer solstice. "No writing to record this great discovery. Lost in the mists of time!" the late astronomer Owen Gingerich noted a few years back.
• Celebrations: Find out where the most notable solstice-themed events are taking place worldwide, courtesy of Conde Nast Traveler.

(More summer solstice stories.)