Color was explained in the Flame Challenge contest for 2014. Coming up with a way to explain color is not easy, which may come as a surprise to many. We talk about colors in our daily lives without giving too much thought to what color actually is. People tend to agree about calling something red or green but no one thinks about what it actually means to say that something is red or green.
This difficulty in explaining color accurately is what prompted the Center for Communicating Science to pose the question “What is Color?” as the 2014 Flame Challenge contest question. Contestants in the Flame Challenge had to come up with a way to explain color to a child so that it was easily understood. Children voted to choose the winner of the contest.
The winners of the Flame Challenge for 2014 were Melanie Golob (written category) and Dianna Cowwern (visual category). The announcement was made by Alan Alda, a founding member of the Center for Communicating Science, at the World Science Festival. There were 400 entries and more than 27,000 children helped to pick the winners.
Cowwern submitted a video that had viewers imagining themselves as a color that takes a journey from a wavelength of light to a brain signal to finally a perception. Golob’s written entry was, “Color itself isn’t a thing we can touch, like a pencil or book; color is how our eyes interpret reflection of light off of certain objects…That’s why we don’t see colors in the dark; there’s no light to reflect.”
At the World Science Festival event, Jay Neitz, a color vision scientist from the University of Seattle, gave a demonstration and told the audience about color perception. He emphasized that color is not something that in inherent in the object but is something that happens in the brain. Color is the brain’s reaction to the wavelengths of light that reach the retina in the eye.
Isaac Newton was the first to recognize that color was not in the light or the object but was a matter of perception. He famously said, “The rays are not colored”, which means the color was not in the rays of light.
To say that color is a perception means that color is a property of the mind. We say that a shirt is red, but the shirt is actually not red. We perceive the shirt to be red in our minds. Redness is a perception based on a predominance of long-wavelength light (say about 650 nanometers in wavelength) reaching the eye and being processed by the brain. The brain assesses the relative amounts of the various wavelengths of light and, if the longer wavelengths predominate, then the perception is towards the red end of the rainbow of colors. If the shorter wavelengths are predominant, then the perception is towards the blue end of the rainbow. Middle wavelengths produce perceptions of green or yellow.
Explaining color as the task of the Flame Challenge for the year was a good choice. A good follow-up question for a challenge would be to explain why the sky is blue. Try it yourself!
By Margaret Lutze