FYFD

Tag: physics

  • Featured Video Play Icon

    “Self-pollination in a flower of thymeleaf speedwell (Veronica serpyllifolia)”

    Though we rarely notice their movement in the moment, plants, and especially their flowers, are frequently on the move. Here, retired engineer Jay McClellan captures a thymeleaf speedwell flower as it opens, then pushes a stamen toward its pistil, thereby pollinating itself. Like much of the motion executed by plants, these movements come from pumping water between different cells, swelling and shrinking them as needed to execute the overall motion. (Video and image credit: J. McClellan; via Colossal)

  • Closing a Venus Fly Trap

    Closing a Venus Fly Trap

    The Venus fly trap has long fascinated scientists with its ability to catch fast-moving prey. Just how the plant closes its “trap” leaf so quickly is a matter of debate. A new study gives us more detail–but not complete clarity–about what’s going on.

    One way that plants move rapidly is by moving water into or out of cells, changing their internal pressure. The new experiments showed that this is not what the fly trap does. Specifically, by watching the speed at which individual Venus fly trap cells take up water, the team concluded that closing the leaf would take 30-150 seconds–far more than the 1 second observed.

    Instead, the team showed that the trap’s rapid closure happens because the plant’s cell walls rapidly soften, making the leaf unable to stay open against previously-stored elastic energy. Instead, the trap snaps closed. The physical mechanism behind the softening is still unclear, though, so the charismatic plant still has mysteries for us to discover. (Image credit: N. Suzuki; research credit: J. Ryu et al.; via Nature and Gizmodo)

    Fediverse Reactions
  • A Special Trio of Clouds

    A Special Trio of Clouds

    Off the coast of Alaska, March 19th, 2026 featured a trio of fascinating clouds. Southwest of Anchorage, a cyclonic polar low twisted up from cold polar air centered over warmer waters. This particular storm boasted tropical-storm-force winds and thunderstorms in its center.

    Further west, long cloud streets formed parallel to the wind as cold dry air picked up moisture from warmer polar waters. And, finally, in the bottom left of the image, alternating vortices swirl in the wake of a rocky island, forming a beautiful von Karman vortex street. (Image credit: M. Garrison/NASA Earth Observatory)

    A trio of atmospheric phenomena appear in this satellite image off Alaska: a polar low, cloud streets, and a von Karman vortex street.

  • Dropping Oobleck

    Dropping Oobleck

    Oobleck is a peculiar substance. Formed from a suspension of cornstarch particles in water, it can flow like a liquid at low shear rates or jam into a solid under impact. Here, researchers explore what happens to a droplet of oobleck impacting a surface. As they expected, the team found that dilute drops could spread like a normal liquid during impact (top), and denser suspensions could impact like a solid would (below). But at the right conditions, they found that cornstarch-rich droplets could show liquid-like behavior at high shear rates and transition to solid-like behavior once the shear rate slowed down. (Image and research credit: A. Mobaseri et al.; via APS)

    An oobleck drop impacts and acts mostly solid.
  • Featured Video Play Icon

    The Teton Dam Failure

    Engineering failures always leave us with lessons learned. The failure of Teton Dam in 1976 triggered an overhaul in how we manage dam construction and regulation. As Grady describes in this Practical Engineering video, the earthen dam was built with fundamental flaws that allowed water to carve pathways beneath and through the sediment meant to hold it. Although the dam cost $100 million to build, its failure cost the federal government over three times that in claims. (Video and image credit: Practical Engineering)

    Fediverse Reactions
  • Vanishing Spirits: Cognac

    Vanishing Spirits: Cognac

    Years ago, photographer Ernie Button discovered an intriguing stain left behind in his whiskey glass after the last drops evaporated. That discovery led both to beautiful images and an entire scientific paper analyzing how the alcohol, surfactants, and polymers in the whiskey combined to leave such a uniform stain. Over the years, Button continued investigating liquor stains, looking at gin, rice whisky, and aging effects. Here, he’s turned his lens to cognac, producing stains that look like oil slicks, aerial landscapes, and even cartoonish faces! (Image and submission credit: E. Button)

    Fediverse Reactions
  • Oyster Reefs Sequester Nitrogen

    Oyster Reefs Sequester Nitrogen

    The US eastern seaboard was once blanketed with oyster beds, but overharvesting, pollution, and habitat destruction decimated the population. As filter-feeders, oysters are naturally good at cleaning intertidal zones, and the reefs they build by cementing themselves to one another provide valuable habitat for many species of fish. A new study shows that oysters are even more economically valuable than we knew, thanks to their ability to sequester nitrogen.

    Agricultural and industrial run-off carries nitrates into the ocean in high concentrations that trigger deadly phytoplankton blooms, which choke off oxygen levels for larger species like fish. One way to reduce nitrogen levels in the water is denitrification, a process where microbes break down the nitrate into, among other things, inert nitrogen gas. The surface of oyster reefs is one place where this happens. But nitrates that evade these microbes can also get trapped and buried by a growing oyster reef.

    To understand how much nitrogen an oyster reef can bury, researchers studied cores removed from restored oyster beds. Below the top ten centimeters (where microbes do their denitrification), nitrogen levels in the oysters increased, with a square meter of oyster reef, on average, sequestering 6 grams of nitrogen per year, comparable to the amount that microbes removed. But some oyster reefs outperformed others. In particular, intertidal flat reefs–which grow faster–buried more than twice the nitrogen of subtidal reefs.

    The team estimated that, in North Carolina’s Carteret County, oyster reefs sequester some 120,000 kilograms of nitrogen annually, at an economic value of over $3 million. (Image credit: J. Andrews/UNC-Chapel Hill; research credit: A. Smiley et al.; via Eos)

    Fediverse Reactions
  • Brushstrokes in Blue

    Brushstrokes in Blue

    In early February 2026, cold weather swept into southern Florida. The cold fronts churned up sediment and cooled shallow waters, making them denser than the warmer waters of the open ocean. That caused the cooled water to sink off the continental shelf, carrying bright sediment with it. The satellite images of swirling sediment remind me of Impressionist paintings. (Image credit: M. Garrison; via NASA Earth Observatory)

    Zoomed in satellite image showing sediment eddies swept into the ocean.
    Fediverse Reactions
  • Featured Video Play Icon

    Why Unpaved Roads Washboard

    As anyone who has regularly traveled unpaved roads knows, they have a tendency to develop regularly spaced corrugations, otherwise known as washboarding. In addition to shaking cars and passengers, these uneven surfaces make cars harder to control, sicne the wheels can lose contact with the ground entirely at times.

    Unfortunately, this phenomenon is fairly unavoidable. Once you have a wheel moving across a granular surface above a critical speed, you get these self-reinforcing patterns. It’s similar to the way that tidal ripples and sand dunes form, and it’s how you get moguls on a ski run, too!

    Although they’re somewhat inevitable, as Grady describes, engineers are hard at work figuring out how to keep them from forming too quickly. (Video and image credit: Practical Engineering; research credit: N. Taberlet et al. and I. Hewitt et al.)

    Fediverse Reactions
  • Shocked Jets

    Shocked Jets

    Breaking a jet of liquid into droplets lies at the heart of many industrial processes: spray painting, fuel injection, and asthma inhalers, to name a few. Here, researchers are looking at a different method of breaking up a liquid jet: shooting a shock wave along its length. The poster shows five different snapshots of the jet’s response. There are, variously, mists of fine droplets, wavy distortions of the jet, sheets, ligaments, and droplets of many sizes. (Image credit: S. Rao et al.)

    Research poster showing black and white images of liquid jets after a shockwave passed along the length of each jet.
    Research poster showing black and white images of liquid jets after a shock wave passed along the length of each jet.