Celebrating the physics of all that flows with Nicole Sharp, Ph.D.
- Profile
A Sprite From Orbit
A sprite, also known as a red sprite, is an upper-atmospheric electrical discharge sometimes seen from thunderstorms. Unlike lightning, sprites discharge upward from the storm toward the ionosphere. This particular one was captured by an astronaut aboard the International Space Station. That’s a pretty incredible feat because sprites typically only last a millisecond or so.…
Branching Dendrites
This award-winning aerial image by photographer Stuart Chape shows a tidal creek in Lake Cakora, New South Wales, Australia. At first glance, it looks much like any river delta, with branching dendritic paths that split into smaller and smaller waterways. That’s deceptive, though, because very different forces shape this creek. Because tides move in and…
See the Solar Wind
After a solar prominence erupts, strong solar winds flow outward from the sun, carrying energetic particles that can disrupt satellites and trigger auroras if they make their way toward us. In this video, an instrument onboard the ESA/NASA’s Solar Orbiter captures the solar wind in the aftermath of such an eruption. The features seen here…
A Variety of Vortices
Winds parted around the Kuril Islands and left behind a string of vortices in this satellite image from April 2025. This pattern of alternating vortices is known as a von Karman vortex street. The varying directions of the vortex streets show that winds across the islands ranged from southeasterly to southerly. Notice also that the…
Capturing River Waves
Rainfall, ice jams, and dam breaks create surges of high flow that make their way down a river in a wave that stretches tens to thousands of kilometers in length. Traditionally, scientists monitor such flow waves using river gauges, which measure river height at specific locations. But gauges are few and far between on many…
Dancing Metal Droplets
Droplets of a gallium alloy are liquid at room temperature. When spiked with aluminum grains and immersed in a solution of NaOH, the droplets change shape and move in a random fashion. This video delves into the phenomenon, describing how a chemical reaction with the aluminum grains changes the local surface tension and creates Marangoni…
“Creation”
Videographer Vadim Sherbakov’s short film “Creation” is full of glittery vistas created under a macro lens. Shifting, particle-seeded flows shimmer in bright colors. Glistening deltas shift and form, and Marangoni flows generate feathers and tree-like dendritic arms. Macro flows never cease to fascinate. (Video and image credit: V. Sherbakov; via Colossal)
Lava Meets Leidenfrost
Drop water on a surface much hotter than its boiling point, and the liquid will bead up and skitter over the surface, levitated on a cushion of its own vapor. In addition to making the drop hypermobile, this vapor layer insulates it from the heat of the surface, allowing it to survive longer than it…
Inside Cuttlefish Suction
Cuttlefish, like many cephalopods, catch prey with their tentacles. Suction cups along the tentacle help them hold on. In this video, researchers share preliminary studies of what goes on inside these suction cups as they’re detached. The low pressures inside the suction cup cause water to vaporize, temporarily. As seen for both the cuttlefish and…
Venusian Gravity Currents
Radar measurements of Venus‘s surface reveal the remains of many volcanic eruptions. One type of feature, known as a pancake dome, has a very flat top and steep sides; one dome, Narina Tholus, is over 140 kilometers wide. Since their discovery, scientists have been puzzling out how such domes could form. A recent study suggests…