Nature

Umbrella Illusion

Gianni Sarcone

One of my illusions from the late ’90s. Take a look at the colorful umbrellas in Figures A and B of the table below—are they the same or different? About 80% of people will say that Umbrella A has jagged, zigzag edges, while Umbrella B has a smooth, wavy outline. But here’s the trick—you’ve been fooled by the brightness contrast of the rays inside the umbrellas. In reality, both umbrellas are identical in shape, perfectly congruent.

This illusion works even when only the lines of the shapes are emphasized. As demonstrated in the table below, the outline of Umbrella A appears jagged and zigzagged, while Umbrella B seems to have, once again, a smooth, wavy outline.

This illusion shows a phenomenon called curvature blindness, which was rediscovered in 2017 by Japanese psychologist Kohske Takahashi. He created a powerful variant and studied its impact on how we perceive shapes.

© Kohske Takahashi – The wavy lines appear different depending on the background and how the repetitive dark color is applied to them.

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The Illusion of Color in Astrophysics

Gianni Sarcone

Study on Colors in Astrophysics – Ongoing Research

Under specific atmospheric conditions and with the technological tools employed, stars or planets may appear to emit green or blue light to some observers. However, as illustrated in the accompanying diagram, this is often nothing more than an optical illusion. The blue region seen in the diagram is actually a medium gray, entirely desaturated. You can verify this by using Photoshop’s color picker tool (or an analogous method) to check the true color values.

This phenomenon raises interesting questions about how color perception in astrophysics can be influenced by both atmospheric effects and the limitations of observational tools. How much of what we “see” in the cosmos is truly the color of the objects themselves, and how much is a product of the interaction between light, our atmosphere, and the instruments we use to detect it?

Puzzling Colors: Red Between the Lines

Gianni Sarcone

Colors are not as fixed as they seem. The red you see might not be the same red someone else perceives. Your brain constantly interprets colors based on their surroundings, which can lead to surprising illusions.

Take this experiment inspired by the Munker-White effect: all the gray bars in the striped patterns are actually the same shade. Yet, next to blue lines, they appear bluish; beside mixed colors, they seem to shift tones. This is known as color assimilation—where a color takes on the influence of its neighbors.

The same illusion explains simultaneous brightness contrast. In the wine-pouring examples below, the liquid seems to change color in the glass. But actually, the red remains unchanged.

Here’s a simple animated variant of my project: Hard to believe, but the flow of wine stays the same shade of red all the way—from the bottle’s neck, through the pour, and even inside the glass. It’s only your perception that changes!

Even more striking—when cyan lines replace black ones, the liquid pouring from the bottle is actually gray from start to finish, yet it appears to turn into red wine in the glass. In reality, the red is just an illusion—your brain fills in the missing color where none exists.

🔴 See it for yourself! Fine art prints of my color experiments are available here:
👉 https://www.redbubble.com/shop/ap/166097393

⚠ Copyright Notice: My artworks are protected. Any use must include proper credit and a link to the original source. Commercial use is strictly prohibited.

The ‘Sassy Sparkler’ Sea Worm: Nature’s Deep-Sea Light Show

Gianni Sarcone

While exploring the Chile Margin along South America’s coastline, researchers made a dazzling discovery with their robotic explorer, ROV SuBastian: the iridescent ‘sassy sparkler‘ sea worm.

At first glance, this deep-sea polychaete worm appears unremarkable with its bristly body. But as it moves, its shimmering bristles reflect light, creating a pink iridescent glow. The secret lies in nanoscale structures within the bristles that act like prisms, scattering light to produce shifting colors depending on the angle of view.

This optical illusion not only mesmerizes but also serves practical purposes. The worm’s changing hues help with camouflage, communication, and UV protection in the deep ocean.

Polychaetes like the ‘sassy sparkler’ play essential roles in marine ecosystems, thriving in extreme environments like hydrothermal vents and contributing to nutrient cycling in ocean depths.

Beauty, Brains, and Charisma

Gianni Sarcone

Beauty’s been a big deal since ancient Greece, where καλὸς κἀγαθός meant more than just a pretty face. It was the ultimate combo: good looks, brains, and virtue. For the Greeks, this wasn’t just a nice idea—it was how they judged your worth.

Fast forward to now, and beauty is still treated as a golden ticket. If you’re not exactly a head-turner but you’ve made it, chances are you’re pretty smart… Sure, beauty often gets written off as superficial, but Aristotle wasn’t wrong when he said, “Beauty speaks louder than any introduction.” Let’s be honest: good looks are a serious social advantage. People treat you better, offer more opportunities, and generally give you a leg up—whether you’re in school, at work, or even in court. Plus, fairy tales and society are pretty obsessed with tying beauty to success. Studies show that attractive people even get a better deal in the justice system.

But here’s the twist: if a guy who’s no Greek god succeeds, people assume he’s smart. If it’s a woman, they’ll say she’s got “character.” Funny how that works, right?

Luckily, looks fade, and that’s when real beauty shows up in unexpected ways. As Shakespeare said in A Midsummer Night’s Dream: “Love looks not with the eyes, but with the mind.”

Beauty’s a gift you didn’t have to work for. Intelligence, though? That’s earned, much like how a pearl forms in an oyster in response to a parasitic intruder. Life’s challenges are what shape and refine your smarts, one obstacle at a time.

So, sure, beauty’s nice—but it can also be a bit of a double-edged sword. What really counts—whether you’re a looker or not—is CHARISMA. It’s not something you’re born with, but something you build over time. Only the truly determined, the ones who know what they want, actually get it.

Through the Eyes of Insects

Gianni Sarcone

The compound eye is nothing like the human eye, but we often misunderstand how insects see the world. In horror movies, their vision is depicted as a chaotic kaleidoscope. In reality, it’s much more refined—like viewing the world through a crystal-clear glass paperweight. 

What’s even more fascinating? Some insects have vibrant color patterns on their compound eyes that serve a purpose! These patterns act as filters, enhancing contrast to help them spot objects against colorful backgrounds or shielding their eyes from certain wavelengths of light.

Take the Deer Fly and Horse Fly, for example—both flaunt these functional designs. But the Green Lacewing (Chrysopidae) takes the crown for the wildest look. Its compound eyes create a diffraction pattern resembling a sheriff’s star, formed by the countless six-sided “ommatidia” that make up its eye structure.

The Wonders of Compound Eyes

Insect compound eyes are made up of thousands of tiny units called ‘ommatidia’, each acting like a mini-eye. This gives insects a near-panoramic view, perfect for spotting motion and environmental changes. Dragonflies, for example, have around 30,000 ommatidia per eye, making them masters of motion detection.

While human eyes, with their single lens and dense photoreceptors, excel at detail and depth, they lack the wide-field motion awareness of compound eyes. Insects also outshine us in speed, detecting rapid movements crucial for survival.

Many insects see ultraviolet light—something humans can’t. This unique vision aids in finding food, communication, and mating. Compound eyes are a brilliant mix of structure and function!

Mesmerizing Color-Changing Squid

Gianni Sarcone

Squids are basically the chameleons of the sea, and their secret weapon? Chromatophores—tiny skin cells that let them pull off some mind-blowing color changes. Whether it’s blending into a coral reef or throwing out some serious “back off” vibes, these little guys do it all. Right now, though, this squid seems to be saying: “Hey genius, put me back in the water before you turn me into calamari!”

Chromatophores of the Squid: How Do They Work?
Chromatophores are pigment-containing cells found in the skin of squids and other cephalopods. These cells expand and contract to display different colors, allowing the squid to blend into its surroundings, communicate with others, or signal threats. They play a vital role in the squid’s survival.

Suggestive Minimalism

Gianni Sarcone

Draw me a human with just two short, symmetrical curved lines…

In 2012, Lebanese artist Huguette Caland took part in the group show Le corps découvert at the ‘Institut du Monde Arabe’ in Paris. One of her works, Self Portrait (1973)—a petal-pink field humorously cracked by a darker pink, revealing an up-close rear view of a classical nude—was featured on the catalog cover. She also presented whimsical, playful line drawings of breasts, lashes, eyes, lips, noses—noses?—as though lifted from a secret, sensual notebook of an untroubled Shel Silverstein. A sign in the hall restricted entry to those over eighteen… Who knows why, for such innocent visual plays?

The Enigmatic Color of the Sun

Gianni Sarcone

Is yellow the true color of the sun? Our sun emits a broad spectrum of radiation, including visible light, which is crucial for life on Earth. In the vacuum of space, the sun appears white because it emits light across all wavelengths fairly evenly. However, when this light enters our atmosphere, it encounters air molecules and particles that scatter shorter wavelengths—primarily blue light—more effectively than longer wavelengths like red and yellow.

color of the sun

Simultaneous Color Contrast Explained…

Consider a small, clear disc placed against a blue background. The disc may appear slightly yellow due to the influence of the blue light surrounding it. This visual effect is similar to how we perceive the sun against the blue sky.In essence, while the sun itself emits white light, our atmosphere alters its appearance, leading us to see it as yellowish or orangish at times.

Additionally, not all species perceive colors in the same way. Different animals have varying sensitivities to wavelengths of light. This means their experience of color and light can be quite different from ours.

For more fun facts about color perception and optical illusions, visit Archimedes Lab.