A quarter-century ago, after a deadly terrorist attack raised fiery explosions from the World Trade Center buildings, the US Department of Homeland Security introduced a color-coded advisory system, under which orange signified “High Risk of Terrorist Activities.” For many people, including Dushko Petrovich Córdova, “this ambient, lingering orange signaled that emergency was continuous, a new way of living.” Ours is a world of prison jumpsuits and Home Depot, leaders with an affinity for fake tans and “aptitude for the orange of perpetual crisis,” public health maps of infection rates painted various shades of orange to mark severity, a sky dyed orange by wildfire smoke. We are inundated by the color; it feels, at times, inescapable. Is it really? Follow Córdova to the brilliant end of this stunner.

Once, in the late ’90s, a few years before the dawn of the orange era, I found myself in Montreal for a friend’s wedding. There was a wildfire nearby, and I remember trying to capture the eerie effect of the atmosphere turning orange with the disposable cameras that had been handed out to all the guests. The resulting pictures looked underexposed and nothing more, the otherworldly orange haze rendered mostly regular gray.

So, decades later, in 2023, when photos of smoke from yet another Canadian wildfire began to appear on social media, I was surprised by how well digital photography had captured what had proved so elusive in the late disposable-camera era. The best civilian shot I saw was of the scenery through a window. The cool interior lighting framed the orangeness outside, in the same way that you might frame a sunset, except that instead of a bright band of orange light at the horizon, this orange was everywhere, pressing at all the edges of the window frame and probably trying to get in through the cracks. In another image I saw a gray cat sitting on a windowsill, apparently unperturbed by the wide expanse of horror just behind it.

Ready to test your knowledge of hue, value, and saturation? Rivka Galchen’s latest for The New Yorker is a trove of fascinating details about our understanding of color. Galchen opens with the buzziest tidbit: an experiment conducted by a vision scientist who used a laser to stimulate a selection of his own cone cells and glimpse a color unknown outside of his laboratory. From there, she roams—through philosophy and art history, from studios to pigment shops—complicating our understanding of perception with each new turn of her titular question.

In the children’s novel “The Midnight Fox,” by Betsy Byars, the main character daydreams about digging in his back yard and coming across a “brand-new color.” A friend of mine remembers being captivated by this scene, and trying to picture the color. “I felt like I could conceive of it, but I couldn’t see it,” she said. The eighteenth-century Scottish philosopher David Hume considered at length whether a person who had seen every shade of blue except for one would be able to picture that one un-experienced shade; he concluded that the answer was yes. In my youth, I spent an afternoon wondering if I would have been able to imagine the fluorescent yellow of highlighter markers if I’d never seen it.