Celebrating the physics of all that flows with Nicole Sharp, Ph.D.
- Profile
Playful Martian Dust Devils
The Martian atmosphere lacks the density to support tornado storm systems, but vortices are nevertheless a frequent occurrence. As sun-warmed gases rise, neighboring air rushes in, bringing with it any twisted shred of vorticity it carries. Just as an ice skater pulling her arms in spins faster, the gases spin up, forming a dust devil.…
“Dispersion”
In “Dispersion,” particles spread under the influence of an unseen fluid. Like Roman de Giuli’s work, filmmaker Susi Sie creates macro images that look like ice floes, deserts, and river deltas viewed from above. This similarity of patterns at both large and small scales is a specialty of fluid physics. Just as artists use it…
Inside an Alien Atmosphere
Studying the physics of planetary atmospheres is challenging, not least because we only have a handful of examples to work from in our own solar system. So it’s exciting that researchers have unveiled our first look at the 3D structure of an exoplanet‘s atmosphere. Using ground-based observations, researchers studied WASP-121b, also known as Tylos, an…
Channeling Espresso
Coffee-making continues to be a rich source for physics insight. The roasting and brewing processes are fertile ground for chemistry, physics, and engineering. Recently, one research group has focused on the phenomenon of channeling, where water follows a preferred path through the coffee grounds rather than seeping uniformly through the grounds. Channeling reduces the amount…
Flying Without a Rudder
Aircraft typically use a vertical tail to keep the craft from rolling or yawing. Birds, on the other hand, maneuver their wings and tail feathers to counter unwanted motions. Researchers found that the list of necessary adjustments is quite small: just 4 for the tail and 2 for the wings. Implementing those 6 controllable degrees…
Salt Fingers
Any time a fluid under gravity has areas of differing density, it convects. We’re used to thinking of this in terms of temperature — “hot air rises” — but temperature isn’t the only source of convection. Differences in concentration — like salinity in water — cause convection, too. This video shows a special, more complex…
Arctic Melt
Temperatures in the Arctic are rising faster than elsewhere, triggering more and more melting. Photographer Scott Portelli captured a melting ice shelf protruding into the ocean in this aerial image. Across the top of the frozen landscape, streams and rivers cut through the ice, leading to waterfalls that flood the nearby ocean with freshwater. This…
Atmospheric Rivers Raise Temperatures
Atmospheric rivers are narrow streams of moisture-rich air running from tropical regions to mid- or polar latitudes. Though relatively short-lived, they are capable of carrying — and depositing — more water than the largest rivers. But researchers have found that their impact is not measured in water content alone. Instead, a survey of 43 years’…
Winter in Chicago
Fresh winter snow blankets Chicago in this satellite image. Over on Lake Michigan, ice dots the coastline out to about 20 kilometers from shore. Darker regions near land mark thinner ice being pushed outward by the wind. Further out, the ice appears white and may be thicker thanks to wind-driven ice piling up. (Image credit:…
Measuring Mucus by Dragging Dead Fish
A fish‘s mucus layer is critical; it protects from pathogens, reduces drag in the water, and, in some cases, protects against predators. But little is known about how mucus could affect terrestrial locomotion in species like the northern snakehead, which can breathe out of the water and move across land. So researchers explored the snakehead’s…