Have you noticed that the days are getting shorter as we near the end of summer? Since the summer solstice June 20th , we've already lost just over 1 hour of daylight! The length of daylight will decrease by another hour over the next month at a rate of almost two minutes of daylight per day. It's really one of the first things that I remember understanding about seasons, aside from summer is hot and winter is cold. It's also known as the northern solstice because it occurs when the sun is directly over the Tropic of Cancer in the Northern Hemisphere.
The point on the horizon where the sun appears to rise and set, stops and reverses direction after this day. On the solstice, the sun does not rise precisely in the east, but rises to the north of east and sets to the north of west, meaning it's visible in the sky for a longer period of time. Although the June solstice marks the first day of astronomical summer, it's more common to use meteorological definitions of seasons , making the solstice midsummer or midwinter.
Over the centuries, the June solstice has inspired countless festivals, midsummer celebrations and religious holidays. One of the world's oldest evidence of the summer solstice's importance in culture is Stonehenge in England, a megalithic structure which clearly marks the moment of the June solstice.
And currently it's an average of two minutes of daylight we're losing each day. You can keep track of this yourself, if you wanted to. That way the next time you point out the shorter days and someone looks at you in a funny way, you'll have proof.
For now, you can rest in the fact that I believe you and know exactly what you're talking about. New Country Jess Published: August 25, Share on Facebook Share on Twitter. The sun was up and shining for 12 hours 10 minutes and 11 seconds today where I live in Los Angeles. Yesterday, the sun took 12 hours 8 minutes and 3 seconds to cross the sky. Which, if you do the math, means that today gave us 2 minutes and 8 seconds of additional sunshine.
And, barring an astronomically unlikely solar catastrophy, tomorrow will give us 12 hours 12 minutes and 19 seconds of sunshine—2 minutes and 8 seconds more than today. Today gave us 2 minutes and 8 seconds of additional sunshine. The even better news is that for the next week or so, the minutes of sunshine will continue increasing by 2 minutes and 8 seconds per day. And for the week or so after that, it will continue increasing at the slightly slower pace of about 2 minutes and 7 seconds per day.
In fact, this time period around the vernal or spring equinox—and actually peaking at the equinox—is the time of year when the number of daylight hours is growing the fastest.
But, you might be wondering, why is that? And for that matter, why does the number of daylight hours change at all throughout the year? To answer that, we need to talk about a bit of basic Solar System astronomy. How does Picture Earth and all of its inhabitants happily spinning like a top around its axis once per day.
Now picture that happily spinning top slowly traveling around the Sun once per year. With a bit of thought and perhaps a model made with a flashlight and ball , you should be able to convince yourself that if the axis around which the Earth spins is perfectly lined up with the axis around which it revolves around the Sun, then every location on the planet will always experience 12 hours of day and 12 hours of night—every day, all year long.
Unless you've actually been living in a cave and thus not able to see the comings and goings of day and night , you'll recognize that this doesn't sound like the Solar System we live in at all—from which we can draw the conclusion that these two axes must not actually be aligned.
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