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80 results for “mud color”
- The Perpetually Curious! › Canonical › Biology & HealthArticle
☀️ Sunlight, Skin, and the Quiet Alchemy of Vitamin D
From section: 🧬 Skin tone and the filtering of lightHuman skin contains melanin, a pigment that contributes to skin color and helps protect underlying tissues by absorbing ultraviolet radiation and dissipating much of its energy. Because melanin also attenuates UVB, it can reduce the amount that reaches 7-dehydrocholesterol in the deeper layers of the epidermis.
- The Perpetually Curious! › Canonical › Botanical WondersArticle
🌱 Why Fruits Have Seeds: The Many Ways Plants Begin Again
From section: 🍒 Some fruits turn appetite into transportIn many fleshy fruits, ripening changes color, aroma, texture, acidity, and sugar content. These changes can make the fruit noticeable and rewarding to animals at roughly the time when its seeds are ready for release. …
- The Perpetually Curious! › Canonical › Cosmic ExplorationArticle
🌌 Why Space Feels Cold Among So Many Suns: The Quiet Physics of Cosmic Warmth
From section: 💡 Did You Know?… Under otherwise similar illumination and geometry, two surfaces that look alike in visible light can settle at different temperatures because color alone does not reveal how strongly each absorbs the full solar spectrum or emits infrared radiation.
- The Perpetually Curious! › Canonical › Engineering & TechnologyArticle
🚆 Quiet Power on the Rails: Understanding Hydrogen Trains and Their Emerging Role
From section: 🌱 Water vapor at the stack and the environmental pictureColor terms provide a convenient shorthand, but they do not represent universally standardized emissions categories. Hydrogen produced from natural gas without carbon capture is often called grey hydrogen.
- The Perpetually Curious! › Canonical › Environment & SustainabilityArticle
🌿 Liquid Trees: Microalgae Photobioreactors and the Quiet Art of Urban Breathing
From section: 🏙️ Public liquid trees: one biological idea, different urban forms… Passersby can see changes in the density and color of the culture, observe some of the equipment that supports it, and encounter photosynthesis as an active urban process rather than an invisible scientific abstraction.
- The Perpetually Curious! › Canonical › Planet EarthArticle
🌑 How Coal Is Formed: The Slow Birth of Black Stone Across Deep Time
From section: 🌿 Ancient swamps where coal beginsThe same low-oxygen chemistry that darkens waterlogged mud also helps explain why buried plant remains can escape rapid decay.
- The Perpetually Curious! › Canonical › PhysicsArticle
🌟 When Light Learns to Answer Back: The Quiet Science of Mirrors
From section: 💡 Did You Know✨ Some insects have highly reflective microstructures in their exoskeletons. Microscopic layers can reflect selected wavelengths of light, creating iridescent colors that shift with viewing angle. This is one expression of structural coloration, where tiny physical architecture helps shape visible color.
- The Perpetually Curious! › Canonical › Environment & SustainabilityArticle
🔄 Tides of Plastic: Microplastic Pollution in the Oceans and Its Journey Back to Us
From section: 💡 Did You Know?… These differences are most relevant to measurement and detection, rather than to visible changes in ocean color.
- The Perpetually Curious! › Canonical › Planet EarthArticle
🌫️ Mist Over Ancient Ridges: The Great Smoky Mountains as a Living, Breathing World
From section: 🌄 Roots in deep time: how the Smokies became mountains… Some of the oldest rocks associated with the park are metamorphic and igneous rocks more than 1 billion years old, while many of the rocks that help form the Smokies began as sand, silt, mud, and gravel deposited along ancient marine margins. …
- The Perpetually Curious! › Canonical › Planet EarthArticle
🌊 Niagara Falls, Where Thundering Waters Shape Time
From section: 💡 Did You Know?🧪 The Niagara River carries about 60 tons (about 54 metric tonnes) of dissolved minerals and finely ground rock over the falls each minute, helping give the water its distinctive turquoise‑green color.