FYFD

A lone shark cruises a sandy shoreline in the Maldives in this image from photographer Tim Burgess. Its path parallels the footsteps left by humans on the beach. Between the beach’s sand and the ocean’s deeper water, there’s a narrow stripe of sand ripples. Constantly formed and reformed by the crashing waves, these ripples act […]

When a fluid flows through a porous bed of grains–like sand, soil, or coffee grounds–the flow rate typically increases linearly with pressure. But that’s not the case for espresso, which is typically brewed with 6-9 bars of pressure. Instead, espresso’s flow rate plateaus at around 5 bars, stays constant as pressure increases, and then drops […]

There’s something about watching big, awkwardly-shaped insects taking off that doesn’t get old. In this video from Ant Lab, we see giant stick insects spreading their wings and taking off. It’s interesting to note that they seem to be wing-first in their take-off; it doesn’t look like they’re doing much, if anything to propel themselves […]

Snails have a mucus for every occasion. The grove snail/lemon snail makes five different varieties: one for lubricating its motion, one for adhering to surfaces, one to seal it in its shell for winter, and two to protect against predators. A new study looks at how those different types of mucus differ. The basic building […]

When a heavier fluid sits atop a lighter one, the interface between them can be unstable. This means that even a very slight disturbance will be enough to cause fingers of dense (dark) fluid to sink while fingers of the lighter (white) fluid rise. This is known as the Rayleigh-Taylor instability, and it’s responsible for all […]

Thirteen years ago, I made a prediction that work on how to avoid urinal splashback would win an Ig Nobel Prize. Today, I am, at last, vindicated. Randy Hurd, Zhao Pan, Tadd Truscott, and Kaveeshan Thurairajah shared the 2026 Ig Nobel Prize in Physics for their work designing a splash-free urinal. The culmination of this […]

When New Horizons flew by Pluto, the dwarf planet’s bright heart-shaped glacier at Sputnik Planitia garnered much attention. Now scientists think they’ve found evidence that liquid has flowed recently there. In a new study, they argue that dark regions near the glacier’s edge are likely places where liquid nitrogen flows up through the nitrogen ice […]

Hurricane Katrina’s storm surge flooded roughly 80% of New Orleans when multiple levees breached. In this video, Grady of Practical Engineering breaks down the engineering failures that made Katrina’s flooding so bad. In his typical hands-on fashion, he shows the flaws of the I-wall-topped levee design, and he takes the time to detail how the […]

When it comes to how stars like our Sun work, scientists have long relied on theoretical predictions to describe processes we couldn’t observe firsthand. But new images from our most powerful solar telescope have finally revealed a phenomenon that’s long been predicted: Kelvin-Helmholtz waves on the Sun’s photosphere. Even if the name is unfamiliar, you’re […]

We’re most familiar with the bright, forking lightning bolts that stretch from thunderstorms toward the ground, but there are even more types of lightning. Pictured here is a gigantic jet, a relatively recently-identified atmospheric phenomenon. Gigantic jets occur when a thunderstorm’s electrical charge escapes upward into the ionosphere in less than a second. The red […]

This timelapse from photographer Mike Olbinski shows a supercell thunderstorm that developed over Colorado and headed to Nebraska. The churning convection of the early storm makes for a dramatic backdrop to stormcloud’s growing rotation. By sunset, the sky was lit with lightning, which continued to illuminate the storm well after darkness fell. (Video and image […]

Sperm whales like to nap under the water and away from the waves. They seem to do this in a vertical, head-up orientation. That makes sense, given that their enormous heads, which take up a third of their bodies, are full of oil, wax, and air–all buoyant materials. What’s less obvious is how the whales […]

Urban environments are full of impermeable surfaces. Without enough soil for stormwater to soak into, rain turns into run-off, carrying with it all the dirt, oil, and pollutants it picks up. To keep the run-off from turning into a flood, developers often use retention and detention ponds to collect and slowly release stormwater–sometimes with added […]

For frost to spread on a surface, individual water droplets freeze and then spread the freezing front to a nearby droplet. Frequently that happens through an ice bridge that connects one droplet to the next. On hydrophilic surfaces, the bridge grows along the surface, slowly connected one droplet to the next and the next until […]

Within the Helix Nebula, a planetary nebula about 650 light-years away, knots of dust and gas stream away from the central star. Though they appear small here, each contains a mass similar to the Earth’s, spread out over an area larger than Pluto’s orbit. Although the structures’ origins are not fully understood, an enduring hypothesis […]

Our planet is constantly carved by the flow of wind, water, and ice. These images, all shortlisted by the International Aerial Photographer of the Year competition, highlight those forces. From meandering rivers and spreading deltas to cracked valleys and windswept dunes, flow is all around us. (Image credit: Various Artists/IAPOTY, see images for details; via […]

Realistically modeling rainfall remains an extremely difficult problem. To be practical, results have to be on the scale of kilometers; no one is looking to find out whether rain will fall from one specific cloud over their head. But making that prediction depends on physics that happens at the microscale, where droplets tens of microns […]

Many of us have a mental image of strings vibrating like a swinging jump rope, but that’s not quite what you actually see. Instead, plucked strings often look strangely triangular, as Henry explains in this Minute Physics video. This more complicated shape comes from the way the string’s tension responds to the applied force of […]

Mars was once a warmer, wetter place, swathed in a thick and protective atmosphere. Unlike Earth, Mars lacks a strong global magnetic field, which allows the solar wind to strip its atmosphere, but the exact mechanisms of that process have been unclear. But a new study has caught the process in action. By combining simultaneous […]

Footage of a massive iceberg flipping in Greenland has gone viral. The feat took place off the coast of Ilulissat and was caught on a nearby livestream camera. Icebergs shift like this because they melt unevenly, with submerged areas melting faster. As the underwater shape of the iceberg changes, the buoyant forces shift relative to […]