Celebrating the physics of all that flows with Nicole Sharp, Ph.D.
- Profile
Spreading Spores
Mushrooms are the fruiting bodies of much bigger, largely underground fungi. Being fruit, mushrooms have the job of spreading spores so that the fungus can reproduce. Some mushrooms rely on the wind; others create their own wind. Still others use vortex rings to carry their spores higher. Who knew such fascinating and beautiful physics lies…
Dancing Peanuts
Bartenders in Argentina sometimes entertain patrons by tossing a few peanuts into their beer. Initially, the peanuts sink, but after a few seconds they rise, wreathed in bubbles. Once on the surface, they roll, causing the bubbles to pop, and the peanut sinks once again. The cycle repeats, sometimes for as long as a couple…
Frozen Ripples
Normally, freezing is a slow enough process that transient phenomena like ripples get smoothed out. But with the right conditions, even ripples can get frozen in time. This picture shows a backyard bird bath after a frigid winter storm passed overnight. For much of that time, the wind was active enough to keep the bath’s…
Why Sea Foams
Seawater froths and foams in ways that freshwater rarely does. A new study pinpoints the ocean’s electrolytes as the reason bubbles resist merging there. By studying the final moments before bubbles coalesce in both pure and salt water, researchers found that dissolved salts slow down the drainage of the thin film of liquid between two…
Dust Storms
Hot, dry berg winds swept down from the Namibian highlands and sent these plumes of dust flying out to the Atlantic coast. Another plume — white instead of brown — marks salt dust from the Etosha Pan salt flat. The dust and salt become aerosol particles in the atmosphere — seeds for raindrops to form.…
Black Hole Signature
240 million years ago, pressure waves emanated from a black hole inside the Perseus Galaxy Cluster. Much later, NASA’s Chandra X-Ray Observatory intercepted those waves. Scientists raised the frequency of the signal until it fell within the range of human hearing. And then photographer John White played that sound through a petri dish of water…
Underwater Volcanic Flows
The Hunga Tonga–Hunga Ha’apai volcanic eruption in December 2021 was the most violent in 140 years, and we are still learning from its aftermath. A recent study focuses on the eruption’s incredible underwater flows, which damaged nearly 200 kilometers of underwater cables. From the cables’ locations and the time of service loss, the team calculated…
Scuba-Diving Fly
Mono Lake, three times saltier than the ocean, is an extreme environment by any measure. But for the alkali fly, it’s home. This extremophile insect dives into the lake, protected by a bubble sheath, to eat and lay eggs. The fly’s wings and body are covered in tiny, waxed hairs that repel water. That traps…
Packing Disks
Liquid crystals, bottles of pills, and hoppers of grains can all involve disk-shaped particles. To better understand how disks pack together, researchers studied how disks in a box orient themselves after shaking. They used MRI to observe the disks’ interior packing. The team found that shaking increases the disks’ density, but that increase does not…
Star YY Hya
A team of professional and amateur astronomers discovered and then imaged this previously undiscovered galactic nebula. At the heart of the stellar remnant is a binary star pair. Shock waves of the gas and dust twist and spread in the surrounding space, the remains of an earlier star’s violent eruption. (Image credit: M. Drechsler et…