Celebrating the physics of all that flows with Nicole Sharp, Ph.D.
- Profile
Crowned Jets
If you fill a test tube with water and drop it, the impact causes a pressure wave that travels up from the bottom and creates a focused jet (left). If the impact is strong enough, cavitation bubbles form at the bottom and generate a sheet-like jet around the central one, like a crown (center and…
“Quiet Pulse” and “Another World”
Light shines dimly through the wall of an ice cave in this photograph by Marie-Line Dentler. Shaped by melting, pressure, freezing, and fracture, these structures are dynamic and ethereal. (Image credit: M. Dentler; via Colossal)
Observing Ice Giant Atmospheres
Uranus is one of our solar system’s oddest inhabitants, stuck spinning on its side with a tilted and offset magnetosphere. To better understand it, a team observed the planet for 17 hours with JWST. The near-infrared measurements gave new insight into the planet’s ionosphere, where auroras form. They found that temperatures peaked between 3,000 and…
Bioconvection
Convection isn’t always driven by temperature. Here, researchers explore the convective patterns formed by Thiovulum bacteria. These bacteria are negatively buoyant, meaning they will sink if they aren’t swimming. They also have an asymmetric moment of inertia, so any flow moving past them tends to affect their swimming direction. When let loose in a Hele-Shaw…
Turbulence and Bioluminescence
If you’ve ever seen crashing waves glowing blue, you’ve been treated to bioluminescence. Although many creatures can bioluminesce, tiny dinoflagellates–a type of marine phytoplankton–are one of the easiest to spot. These microscopic organisms create a flash of light in response to viscous stresses. Their response to flow-induced stresses is so robust that they can be…
Colorful Tides
The colorful coastline of the Bazaruto Archipelago extends off East Africa. Regions of shallow waters, seagrass meadows, and coral reefs appear in shades of tan, green, and turquoise. Deeper waters appear blue. The coastlines, deltas, and tidal flats are shaped by moderate tides that rise and fall a few meters each day; strong currents run…
“The Haboob”
Haboobs are a dust storm driven by the strong winds at the forefront of weather fronts and thunderstorms. Those powerful winds pick up dust in arid and semi-arid landscapes, creating billowing, turbulent clouds that appear downright apocalyptic. This particular haboob formed in Arizona in August 2025 and was caught in timelapse by photographer and storm…
Thunderstorms Make Trees Glow
Scientists have long hypothesized that the high electrical charge of thunderstorms could produce an opposite charge in the ground that would discharge from the forest canopy. But this phenomenon, known as a corona, had never been observed on actual trees. A new study, however, has observed this ghostly ultraviolet (UV) glow from the tips of…
Making Sound Visible
Sound is not something we can typically see, though there are ways to visualize it, including cymatics and special acoustic cameras. This video pursues a different tactic: using schlieren photography and stroboscopic lighting to show how sound waves reflect and deflect. It’s no easy feat, but one worth enjoying–especially when others have already done the…
Aging Salty Ice
When ice forms in salty water, it starts out mushy and porous. Salt does not freeze neatly into ice’s crystalline structure, so the forming ice has pores and gaps where salty brine gathers. As the ice ages, more brine is pushed out and gradually convects downward, due to its greater density. Over time, this makes…