Antarctica is nearly fully covered in ice and doubles in surface area each winter as the surrounding sea freezes. So it’s an especially spectacular place for viewing icebergs, like these photographed by Jan Erik Waider. The ice comes in many shapes — some clearly fractured and some sculpted by wind and water. The colors, too, are striking. Even in overcast conditions, the blues of the ice seem almost to glow from within. (Image credit: J. Waider; via Colossal)
North of Iceland’s Fagradalsfjall, a new volcanic fissure opened in July 2023. This drone footage from Isak Finnbogason captures that fissure on its first night. Lava fountains jet from the earth, forming a complex, slow-moving river. The similarities between flowing lava and more common liquids like water never ceases to fascinate me. Even with the vast differences in temperature and viscosity, so much of their physics remains recognizably the same. (Image and video credit: I. Finnbogason; via Colossal)
Colors stream and mix in Rus Khasanov’s short film “Discovery.” Droplet-like liquid lenses float in the mixture until ethanol or other ingredients cause them to spontaneously rupture, sending their interior flowing outward until the lens reaches a new equilibrium. Gradients in surface tension guide Marangoni flows across the screen. There’s never-ending beauty in the world of macro fluids. (Video and image credit: R. Khasanov)
Eighteenth- and nineteenth-century French painters like Chardin and Manet had a certain fascination with bubble-blowing physics. Both left behind artwork depicting children blowing soap bubbles through straws. Now researchers are exploring this bubble-making method in a recent study.
To blow a bubble from a straw or other narrow constriction, there are three basic stages. In the first, the soapy interface bulges and takes on a spherical shape. That’s followed by a period of rapid growth in less than 100 milliseconds. And, finally, the bubble will pinch off and detach from the straw. So far, most studies have focused on that third phase. Instead, this team focused on those early stages.
In that first stage, the bubble’s growth depends on air getting forced out of an attached reservoir. For children, that’s their lungs reducing in volume as they blow air into the straw. In their experiments, the team found that the initial volume of the air reservoir is an important (and previously overlooked) factor in controlling bubble growth. (Image credit: J. Chardin; research credit: M. Grosjean and E. Lorenceau; via Ars Technica)
Expedition guide and photographer Ryan Newburn captures the ephemeral beauty of the glacial caves he explores in Iceland. These caves are in constant flux, thanks to the run and melt of water. The scalloped walls are a sign of this process of melting and dissolution. The icicles, too, hint at ongoing melting and refreezing. Caves can appear and disappear rapidly; they’re a dangerous environ, but Newburn freezes them in time, letting the rest of us experience a piece of their majesty. See more of his images on his Instagram. (Image credit: R. Newburn; via Colossal)
Bright colors mark this slowly draining soap film. The film sits slightly off-horizontal, so flow shifts over time from the top of the frame to the bottom. The fluid is also evaporating. All the faster shifts are caused by ambient air currents from the room. The colors of the film are directly related to the local thickness; as the film thins and evaporates, the bright colors shift to darker ones. Eventually, that black region at the top will expand and the film will break up. (Video credit: B. Sandnes/Complex Flow Lab)
Ruslan Khasanov’s “Space Iris” explores the similarities between nebulae and eyes. Made entirely with common fluids like paint, soap, and alcohol, the film shows off the gorgeous possibilities of surface-tension- and density-driven instabilities. Marangoni flows abound! I even see some hints of solutal convection, perhaps? (Video and image credit: R. Khasanov; via Colossal)
Volcanoes are endlessly fascinating to watch, especially in this era of drone photography. Joey Helms’s short film “The Beauty in Creation” shows the Fagradalsfjall eruption in Iceland. Sail over rivers of lava, watch fountains spurting, and even see lava dripping back into the caldera. They’re views that no human gets to witness directly, but they certainly do highlight the peculiar collision of destruction and creation inherent in volcanic eruption. (Video credit: J. Helms)
From above, the salt marshes of Alviso Marina County Park look like veins and capillaries in this photo from Tayfun Coskun. The waterways curve and branch, forming fractal patterns only apparent from the air. Although the mechanisms that form these dendritic patterns vary, they are very common in fluids, appearing over and over at many scales. (Image credit: T. Coskun; via Gizmodo)
Not every experiment turns out as expected. Photographer Julien Looten expected to capture the Milky Way arching across the sky above this French chateau. But the photo’s most striking feature is instead the airglow suffusing the sky. The psychedelic colors result from air high in Earth’s atmosphere getting excited by sunlight and producing a faint glow of its own. Such airglow is common, though not always easily seen. If you watch videos from the ISS, you may notice the orange arc of airglow over the atmosphere. (Image credit: J. Looten; via APOD)