Buzz
Many of us hold incorrect beliefs about colors, such as the idea that the sun appears yellow or that nighttime is completely black. Additionally, we often mistakenly believe water has no color, gold is purely gold, and that rainbows consist of only seven colors.
The process of perceiving color is far more complex than it seems. Factors like science, our eyes, brain, and even language influence how we interpret colors. For instance, we can only recognize colors that have been named, leading to frequent misidentification of unnamed shades. A prime example is blue, which was historically referred to as green. Yet, blue isn’t the only color with a disputed past.
10. The Color We Perceive in Darkness Isn’t Black
What shade do we see at night? Many assume it’s black, but it’s actually eigengrau. This German term translates to “intrinsic gray” or “own gray,” and is also known as Eigenlicht, meaning “intrinsic light.” Eigengrau is slightly lighter than pure black and is represented by the hex code #16161d in graphic design.
The concept that we perceive eigengrau instead of black at night was initially introduced by German physicist Gustav Theodor Fechner in the 19th century. Prior to this, it was universally accepted that we saw pure black. Fechner also noted that eigengrau resembles the background color of the patterns visible when our eyes are closed.
Although eigengrau is seldom discussed in modern scientific circles, it’s widely acknowledged that we don’t see true black at night. There’s always a faint visibility, and a black object will appear darker than its surroundings, which wouldn’t be possible if both the night and the object were entirely black.
9. The Color Pink Doesn’t Truly Exist
The existence of the color pink is a topic of debate among scientists. While some argue it exists, others claim it doesn’t. However, we all perceive pink. How can a visible color not exist? The truth is, pink exists as a color, but there’s no such thing as pink light.
Many assume that every color corresponds to a specific wavelength of light, meaning all colors appear in the rainbow. (Black and white are exceptions as they aren’t considered true colors.) This is incorrect. Pink doesn’t appear in the rainbow and lacks a corresponding wavelength of light.
Pink light can only occur naturally if red light from the rainbow somehow intersects with violet light. However, this is impossible because red and violet are positioned at opposite ends of the rainbow. They will never meet unless some extraordinary force rearranges the rainbow’s color sequence.
8. The Rainbow Doesn’t Have Seven Colors
How many colors does a rainbow contain? Ancient cultures had varying opinions. Homer, the Greek poet, believed the rainbow consisted of a single color: purple. Meanwhile, the philosopher Xenophanes argued for three colors: red, yellow-green, and purple.
During the Renaissance (1300s to 1600s), it was widely accepted that the rainbow had four colors: red, yellow, green, and blue. Later, a fifth color, purple, was added. Today, most people argue for six or seven colors, though the Chinese maintain their belief in a five-color rainbow.
This raises the question: why do people have such differing views on the number of colors in a rainbow? It seems like a straightforward observation, given that everyone has seen a rainbow.
The reality is: the number of colors in a rainbow depends on the observer. Since there are no distinct boundaries between the colors, people tend to identify only the colors they know. Someone with extensive knowledge of colors might perceive hundreds, while someone with limited understanding may see fewer than seven.
The modern 7-color rainbow was conceptualized by Sir Isaac Newton in 1666. At the time, the general belief was that the rainbow had five colors. However, Newton, who believed the universe operated in sevens, decided otherwise.
Newton’s reasoning was based on the prevalence of the number seven: seven days in a week, seven known planets (before Uranus and Pluto were discovered), and seven notes in a musical scale. Consequently, he incorrectly concluded the rainbow must have seven colors, adding orange between red and yellow and dividing purple into indigo and violet.
7. Water Isn’t Truly Colorless
If you ask someone to describe pure water, they’ll likely say it’s tasteless, odorless, and colorless. While the first two are accurate, the third is not. Pure water actually has a faint blue tint.
The faint blue hue of pure water differs from the blue we see in the ocean. The ocean appears blue because water molecules absorb longer wavelengths of light (red, orange, and yellow) and reflect shorter wavelengths (blue). This phenomenon is similar to why the sky appears blue, except in that case, it’s the atmosphere absorbing and reflecting light.
Pure water is nearly impossible to find in nature, as natural water always contains impurities like minerals and sediments. However, distilled water can be created in controlled laboratory conditions. While it may seem colorless in small amounts, its light blue tint becomes visible when observed in large quantities.
6. The Color of Gold Isn’t What You Think
While it’s true that gold has a distinct color, it’s not as straightforward as it seems. The color gold, often referred to as golden, is actually a shade of yellow. This is interesting because gold, like silver, might be expected to have a silvery appearance.
Gold’s unique color is explained by relativistic quantum chemistry. This theory suggests that when atoms move at extremely high speeds and cannot accelerate further, any additional energy increases their mass instead of their speed. This added mass, known as relativistic mass, influences gold’s distinctive yellow hue.
Understanding relativistic mass is essential because it can change an object’s color. As previously mentioned, gold should theoretically have a silvery appearance. However, its atoms move at 58% the speed of light, making it impossible to accelerate them further. This causes the atoms to absorb blue light (with its shorter wavelength) and reflect yellow light, which has a longer wavelength.
5. Space Isn’t as Colorful as It Seems
If your perception of space is based on stunning images from space agencies, you might assume it’s vibrant and colorful. However, astronauts who’ve been there describe it as far less exciting, with little more than scattered dots of light visible.
Even with a telescope, space appears mostly devoid of color. Many celestial bodies emit light outside the visible spectrum, and those that don’t are typically red or blue—the most common colors in the universe. So, where do those vivid space photos come from?
Here’s the truth: nearly every image you’ve seen of space, celestial bodies like planets and comets, or cosmic events like supernovae, is artificially enhanced. Before conspiracy theories arise, it’s important to clarify that the photos themselves are real, but the colors are often added or altered.
NASA enhances its space photos by adding colors to emphasize key features, reveal light wavelengths invisible to the human eye, and spark public interest. Without these enhancements, space imagery would be dominated by shades of blue and red, which might fail to captivate audiences. By incorporating colors like orange, green, and purple, NASA makes these images more visually appealing and engaging.
4. Not All Colors Are Visible to the Human Eye
Contrary to popular belief, there are colors we may never perceive, no matter how hard we try. Two such colors are red-green and blue-yellow. These aren’t mixtures like reddish-green or bluish-yellow but rather distinct hues that blend red and green or blue and yellow into a single, indivisible color. Imagine a shade that is equally red and green or blue and yellow.
These elusive shades are known as forbidden colors. Their invisibility stems from how our eyes and brain process color. Specialized cells called opponent neurons are responsible for detecting colors. These neurons activate or deactivate depending on the color they perceive. However, the same neuron that activates for red deactivates for green, creating a conflict when encountering red-green.
This conflict prevents us from perceiving red-green. Similarly, the neuron that activates for yellow deactivates for blue, making blue-yellow equally impossible to see. Essentially, our visual system cannot simultaneously process these opposing colors, rendering them invisible to us.
3. The Sun Isn’t Yellow
Many people mistakenly believe the sun is yellow, but in reality, it’s pure white. This becomes evident when sunlight is passed through a prism, breaking it into the colors of the rainbow. If these colors were recombined, they would produce white light, confirming the sun’s true color.
The misconception about the sun being yellow stems from Earth’s atmosphere and images from organizations like NASA. Our atmosphere scatters shorter wavelengths of light, such as blue, indigo, and violet, while allowing longer wavelengths like red, orange, and yellow to pass through. This scattering effect makes the sun appear yellow to us.
As the sun sets, it appears redder because the atmosphere scatters shorter wavelengths more effectively. Smoke and pollutants in the air further enhance this effect by scattering blue, indigo, and violet light, intensifying the red appearance.
Interestingly, when the sun is directly overhead, it sometimes takes on a slight blue tint. This occurs because the atmosphere struggles to scatter blue light at that angle. Additionally, NASA often colors the sun yellow in its images to emphasize its features, which further perpetuates the misconception.
2. Not Everyone Perceives Colors the Same Way
Does the language we use shape how we perceive colors? Absolutely. The colors we recognize and name are heavily influenced by the language we speak.
We tend to identify only those colors for which we have names. When encountering an unfamiliar color, we often associate it with the closest named color, even if they aren’t truly similar. This phenomenon is particularly noticeable with blue, which was historically regarded as a variation of green.
Cultures worldwide developed color terminology in a similar pattern. Initially, they named white and black (or light and dark), followed by red, due to its association with blood and wine. Next came either yellow or green, with the other following shortly after.
Blue was consistently one of the last colors to be named. In fact, it emerged relatively recently in human history. The ancient Egyptians were an exception, as they had a term for blue, thanks to their access to blue dye. Other cultures simply classified blue as a shade of green.
To demonstrate this, researcher Jules Davidoff visited Namibia to study the Himba people, who lack a distinct word for the color blue. He presented them with an image of 12 squares—11 green and one blue—and asked them to identify the odd one out. Most tribesmen struggled to distinguish the blue square.
Interestingly, when shown another set of squares, all green but with one lighter shade, the Himba people quickly identified the different square. This was because their language includes multiple terms for various shades of green, making the task easier for them.
In contrast, English speakers would easily spot the blue square in the first image due to our distinct names for blue and green. However, we would struggle with the lighter green square in the second image, as our language lacks specific terms for different green shades.
1. New Colors Can Be Created
While it might seem that all colors are derived from the primary colors—red, blue, and yellow—this isn’t entirely true. It’s entirely possible to invent new colors, and we’ve already created at least three: yinmn blue, ntp yellow, and vantablack.
Yinmn blue, derived from yttrium, indium, and manganese, was first synthesized by Professor Mas Subramanian in 2009. Similarly, Niobium Tin Pyrochlore yellow, also known as ntp yellow, was developed by Simon Boocock for the Shepherd Color Company in 2010.
Boocock designed ntp yellow to replace pigment yellow 34 (PY 34), which was once the most widely used yellow pigment, commonly found in safety signs. However, PY 34 is toxic and prone to fading, leading to the development of this safer and more durable alternative.
Lastly, there’s vantablack, a shade of black so intense that it surpasses conventional black. Unlike typical pigments that reflect light, vantablack absorbs nearly all light, creating an appearance akin to a black hole. This groundbreaking color was created by Surrey NanoSystems.
