As charged particles from the solar wind bombard the upper atmosphere, a glowing plasma forms and dances in the sky. The green light of the plasma reflects off moistened sand, rippled by the passage of wind and tide. Each component seems simple, but this striking image contains hidden depths of fluid dynamics. Magnetohydrodynamics govern the aurora’s dance; the sand’s self-organization mirrors dune physics; and even the rocky outcropping in the background was carefully shaped by erosive forces from wind and water. Truly, fluid dynamics are found everywhere. (Image credit: L. Tenti; via 2023 Astronomy POTY)
Tag: fluids as art
“A Sun Question”
The sun‘s surface and atmosphere are endlessly dynamic, with magnetic lines, plasma, and convection creating a constant churn. In this photo by astrophotographer Eduardo Schaberger Poupeau, a curving question-mark-like filament appears above the sun’s surface. Even with decades of high-resolution data from recent solar probes, we struggle to understand the complex physics that feed structures like these. (Image credit: E. Poupeau; via 2023 Astronomy POTY)
Ghosts of Rivers Past
Artist Dan Coe uses lidar data to create portraits of rivers and their past meanders. Used aerially, lidar produces high-resolution elevation data that provides a glimpse of features that are currently hidden beneath vegetation. With rivers, this means unearthing some of their previous paths. Secondary flows in a river bend erode the bed so that the bend gets more and more strongly curved. Eventually, the river can double back on itself and cut off the long curve. Repeat that process over millennia and you wind up with the complex paths in Coe’s images. (Image credit: D. Coe; via Colossal)
Slumping Ceramics
Dripping, drooping pottery is artist Philip Kupferschmidt’s specialty. Covered in drips and drops, slumping as if half-melted, Kupferschmidt’s ceramics seem partially liquid. With their colorful glazes, these pieces ooze personality. (Image credit: P. Kupferschmidt; via Colossal)
Melting Ice Cap
This award-winning photo by Thomas Vijayan shows waterfalls of ice melt off the Austfonna ice cap. The third-largest glacier in Europe, Austfonna is located in Norway’s Svalbard archipelago. Like other glaciers, it sees rising temperatures and increased melting due to climate change. Vijayan highlights that melting with his focus on the many waterfalls slicing through the ice. All that meltwater contributes to changes in local salinity as well as rising sea levels worldwide. (Image credit: T. Vijayan; via Nature TTL POTY)
“Animaris Rex”
Eighteen meters long and powered only by the wind, artist Theo Jansen’s latest Strandbeest strolls the sand in this short video. Its complex movements — a swinging gait in some places and a caterpillar-like wave in others — are mesmerizing and life-like enough to almost make you wonder if the contraption truly is alive. See some of Jansen’s previous creations here. (Video and image credit: T. Jansen et al.; via Colossal)
“Shaken, Not Stirred”
James Bond notoriously orders his martinis “shaken, not stirred,” a request bartenders fulfill by shaking the cocktail over ice in a separate shaker. But what if you shake the martini glass itself? That’s the question that inspired this lovely mixology.
By shaking the martini glass gently back and forth (along the directions shown by the arrows in each image), the team created different mixing patterns within the glass. With a little food dye and pearl dust, they visualized the flows they found. By changing the viscosity of the cocktail and the speed of the swish, they made everything from a four-leaf clover to a cadre of ghosts. It seems that martini glasses hold a flow for every occasion! (Image and research credit: X. Song et al.; submitted by Zhao P.)
GFM poster, describing the experiments used to create these picturesque martinis. 
Eroding the Sphinx
One theory suggests that the Great Sphinx of Giza formed — in part — naturally as a result of erosion, and ancient Egyptians added features to the bedrock formation. To test the plausibility of the theory, researchers made a miniature sphinx, consisting of a clay mound with a single, harder inclusion to represent the Sphinx’s head, and placed their construction in a water tunnel. As the water eroded away the clay, the head appeared, and flow around this harder-to-erode region formed some of the body and paws of the reclining Sphinx.
The experiment suggests that it is plausible for part of the Sphinx to have formed naturally, as a result of erosion. But plausibility is not proof, and given the lack of a contemporary inscription explaining the statue’s origin, the goals and methods of the people who built it around 2500 B.C.E. will remain a matter of archaeological debate. (Image credit: S. Boury et al.)
“Chaosmosis”
After many years of featuring work from the Gallery of Fluid Motion, I’m excited to announce a new public exhibition of art drawn from the competition: “Chaosmosis: Assigning Rhythm to the Turbulent.” Works in the exhibit come from both scientists and artists; each piece makes visible the fluid motions that surround us.
The exhibit is located at the National Academy of Sciences in Washington, DC through February 23, 2024. Entry is free, but only available between 9 a.m. and 5 p.m. on weekdays. For more, check out the exhibit’s webpage and press release (pdf) and the Instagram accounts for CPNAS and the exhibit.
I’m looking forward to seeing the exhibit when I’m at the APS DFD meeting next month, but if you can’t make it to DC before the exhibit ends, don’t worry! This is just the first stop for the new traveling GFM exhibit. (Image credits: various, see individual images’ titles)
Red Sprites
Sprites, or red sprites, are high-altitude electrical discharges in the atmosphere. Although sometimes called upper-atmospheric lightning, sprites are a cold plasma phenomenon. They often occur in clusters, as in this photo by Angel An, which won in the Skyscapes category of the 2023 Astronomy Photographer of the Year competition. Sprites, which last only a millisecond or so, take place during intense thunderstorms, but, unlike our more familiar lightning, sprites move upward from the storm toward the ionosphere. They can occur on Venus, Saturn, and Jupiter as well, although sprites have only been observed directly on Earth and Jupiter. (Image credit: A. An; via Colossal)
