Page 37 - WVG2017
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Why are the Ojai Valley’s sunsets so beautiful?
During a recent late fall after- noon in Ojai, a convergence began at Meditation Mount's lookout point on the east
side of the valley. The gathering began at approximately 4 p.m with fewer than 10 people observing the valley's waning light.
Slowly, the group became larger. By 4:30 p.m., the group had doubled, all waiting in relative silence for the sun to drop behind the intervening mountains.
By 4:45 p.m., the sun was broad- casting shades of pink, orange and red across the sky.
Shortly thereafter, with the sun
no longer visible, they turned east the see the Topa Topa Mountains awash in color.
It was the pink moment.
A 1973 publication, “Guide to the Beautiful Ojai Valley,” includes a section titled, “How to speak Ojai-
Story by Andra Belknap
ese.” One of the terms defined is “pink moment.”
“At sunset, Topa Bluff to the east is diffused with a soft pink glow, as the dying rays of the sun are reflected back over the valley,” the guide explains.
Ojai isn't the only valley to experi- ence a pink moment, “but ours is kind of the best of the bunch,” said local astronomer Ernest Underhay.
The Topa Topa Mountains are made of a light sandstone that reflect the colors of the setting sun, he said.
The science behind the pink mo- ment is pretty simple — it's the same reason the sky is blue, said Thacher School astrophysicist Jon Swift.
“It's actually the same phenome- non, you're just looking at a different facet of that phenomenon,” he noted. “When light from the sun interacts with our atmosphere, our atmosphere preferentially scatters the blue light, so when the sunlight hits our atmosphere, blue light, preferentially, is scattered
in all directions, and that's why you can look up at the sky during the day, if there are no clouds, and everywhere you look, it's blue.”
Preferential scattering refers to the way light waves interact with the par- ticles in the Earth's atmosphere. Blue light waves are shorter than red light waves. Blue light waves tend to inter- act with particles in the atmosphere, due to their size, and “scatter.”
“When the sun gets low in the sky, in the evening or in the dawn hours,
the light has to travel through more and more atmosphere to get to your eyeball, and when it's going through more and more atmosphere, that means that more and more blue light is getting depleted from the light that's making it to your eyeball,” Swift said. “The more and more blue light, or short wave length light, that gets scattered out of our line of sight, the redder and redder the sun starts to look, until it gets down really low.”
“In Ojai,
Continued on page 40
Photo by Tania Parker

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