Celebrating the physics of all that flows with Nicole Sharp, Ph.D.
- Profile
Solar Filament Eruption
From Earth, we rarely glimpse the violent flows of our home star. Here, a filament erupts from the photosphere creating a coronal mass ejection, captured in ultraviolet wavelengths by the Solar Dynamics Observatory. This particular eruption took place in 2012, and, while it was not aimed at the Earth, it did create auroras here a…
“The Art of Flying”
Like schools of fish, starlings gather in massive undulating crowds. Known as murmurations, these gatherings are a type of collective motion. Scientists often try to mimic these groups through simulations and lab experiments where individuals in a swarm obey simple rules that depend only on observing their neighbors. It requires very little, it turns out,…
Venusian Lava Flows
Venus is often known as Earth’s twin, given its similar size and proximity. But, thanks to its runaway greenhouse effect, Venus is a hellish landscape buried beneath a hot atmosphere of carbon dioxide and sulfuric acid. Unlike Earth, Venus is not tectonically active, though it does have active volcanoes. A recent study re-examined synthetic aperture…
Playing With Water in 2D Containers
Once again Steve Mould is putting his prototyping skills to use to work out what goes on inside tricky containers. Here he looks at a “magic” wizard’s cup where — like the assassin’s teapot — cleverly placed holes in the side of the cup can block or allow air’s escape. In the wizard’s cup this…
Saving Energy By Following a Leader
Scientists have long suspected that birds save energy by following a leader — think of the V-shaped flight formation used by geese — but a new study captures that savings directly. The team studied starlings, flying singly or in groups of two or three, in a special wind tunnel. Each bird wore a tiny backpack…
The Real Butterfly Effect
The butterfly effect — that the flapping of a butterfly’s wings in Brazil can cause a tornado in Texas — expresses the sensitivity of a chaotic system to initial conditions. In essence, because we can’t possibly track every butterfly in Brazil, we’ll never perfectly predict tornadoes in Texas, even if the equations behind our weather…
Making a Splash
Since Harold Edgerton’s experiments with stroboscopic photographs in the 1930s, we’ve been fascinated by the shape of splashes. These days students and artists can take advantage of programmable external flashes to capture this split-second moment of impact. Here, a pink-dyed drop of ethanol strikes a jet rising from a pool of glycerin, milk, and food…
How Water Droplets Charge Up
Rubbing a balloon on your hair can build a significant electrical charge. Water droplets have the same issue when they slide across a hydrophobic, electrically-insulated surface. A new study models why these charges build up and tests the model both experimentally and through simulation. They focused their theory on three effects that determine how much…
Mardi Gras Pass
The mighty Mississippi River has long been bound by humanity’s efforts. To keep the river in place and control its flooding, engineers have built levees, canals, and other structures. But those efforts have come with costs. Where the wild Mississippi used to deposit sediment and build new land, the bound river sends its sediment out…
How to Run on Water
Ahead of the Olympics, I’ve written a feature article for Physics World that explores how basilisk lizards and grebes run on water and what it would take for a human runner to do the same. Check it out! (Image credit: B. Mate; see Physics World)