This year, the June solstice falls on two different days: Wednesday, the 21st, for those in Eastern Standard Time, and Tuesday, the 20th, for time zones further west!. Enjoy seven cool (or, is it hot?) solstice facts—and see how many you know!
If you ask friends what happens on the summer solstice, they’re likely to get it right. It’s the longest day of the year, meaning, the most minutes of sunshine. And the midday Sun is highest up in the sky, or lowest if you live in the Southern Hemisphere.
But now look more deeply …
- What’s not widely known is that on the solstice, the Sun moves through the sky along its most curving path. It rises and keeps veering to the right as it passes high overhead—quite different from the laser-straight path the Sun moves along in late March and late September.
It’s fun to share little-known facts about the Sun. For example, not many are aware that the kind of energy the Sun emits most strongly is not ultraviolet, or gamma rays, or even visible light. It’s actually infra-red. That’s the Sun’s strongest emission. The kind we feel as heat.
As for the Sun’s visible emissions, its strongest is: Green light. That’s why our eyes are maximally sensitive to that color.
More Solstice Facts
Let’s continue with more fun facts about the Sun, but limit them to the solstice.
- The solstice Sun stands directly over the Tropic of Cancer. In fact, that’s how the topic of cancer got its name. It’s the southernmost line connecting all places on Earth where the Sun is ever straight up. That’s because a few thousand years ago, the solstice happened when the Sun was in the constellation of Cancer the Crab. Thanks to the wobble of our axis, this Wednesday, the Sun is in the constellation of Taurus the Bull. So somebody should go down there and change all the signs to Tropic of Taurus.
- This Wednesday’s solstice is when folks in the Northern Hemisphere see the highest Sun of the year. But it’s getting less high over time. That’s because Earth’s tilt is slowly decreasing.
- The solstice is when the Sun is lowest in the sky for those at the equator.
- The word solstice comes from the two Latin words “sun” and “stoppage.” Makes sense: the Sun stops moving north that day.
- In India, the summer solstice ends the six-month period when spiritual growth is supposedly easiest. Better hurry, you only have a few days left.
- That day, the Sun rises farthest left on the horizon, and sets at its rightmost possible spot. Sunlight strikes places in your rooms that get illuminated at no other time.
With all that, most people care about one single solstice fact:
“It’s the start of summer!” (Or, winter, if you live below the equator).
Live Show! Celebrate the Solstice!
On Wednesday, June 21, at 5:00 PM EDT (2:00 PM PDT), celebrate the solstice with a live event, featuring extraordinary views of the Sun streamed from Slooh observatory partners all over the world, including close-up views from Prescott Observatory in Prescott, Arizona, wide angle views from New York City, Chicago, Seattle, Hawaii, and other locations around the globe. This year, Slooh’s solstice show also features several astronomy experts speaking about the solstice, including Bill Nye The Science Guy and Phil Plait, The Bad Astronomer, who will also preview 2017’s biggest event, the Transcontinental Total Solar Eclipse, which will sweep across the continental U.S. on August 21. Wow! Click here to watch the Summer Solstice Show—for free, compliments of Slooh.