Tag: science

Mud Pots
Mud pots, or mud volcanoes, form when volcanic gases escape underlying magma and rise through water and earth to form bubbling mud pits. I had the chance to watch some at Yellowstone National Park a few years ago and they are bizarrely fascinating. In this Physics Girl video, Dianna recounts her adventures in trying to locate some mud pots in southern California and explains the geology that enables them there. And if you haven’t seen it yet, check out her related video on the only known moving mud puddle! (Image and video credit: Physics Girl)
July 20, 2021
Devising Greener Chemistry
Not all microfluidic devices use tiny channels to pump and mix fluids. Some, like the Vortex Fluidic Device (VFD), conduct their microfluidic mixing in thin films of fluid. The VFD is essentially a tube spinning at several thousand RPM that can be tilted to various angles. Coriolis forces, shear, and Faraday instabilities in the thin fluid film create a complex microfluidic flow field that’s excellent for mixing, crystallization, and processing of injected chemicals. One rather notorious application of this device was unboiling an egg, a feat for which the researchers won an Ig Nobel Prize. But other, more practical applications abound, including a waste-free method for coating particles. (Image and research credit: T. Alharbi et al.; video credit: Flinders University; via Cosmos; submitted by Marc A.)

July 19, 2021
Inside Old-Fashioned Butter
Today’s video is a little different: it’s an inside look at a butter-making shop in France that uses traditional nineteenth-century methods to process the butter. Watching workers fold and shape 50 kilos of butter is mesmerizing, and it highlights the amorphous, pseudo-fluid nature of the butter. Yes, the butter holds its shape like a solid, but it’s a soft solid at best and certainly shows fluid-like qualities when force is applied. A word of warning: you might not want to watch this on an empty stomach! (Image and video credit: Art Insider; via Colossal)
July 16, 2021
Suspended Sediments in Lake Erie
Lake Erie’s Long Point is outlined in turquoise in this natural-color satellite image. The pale color is likely due to limestone sediments in the shallow waters getting resuspended by a seiche or other disturbance. A seiche is a standing wave that forms in a partially- or fully-bounded body of water; in Lake Erie they are typically wind- and weather-driven. (Image credit: J. Stevens/USGS; via NASA Earth Observatory)
July 15, 2021
Martian Polar Troughs
Mars‘s northern pole is capped by a spiral-like pattern of deep troughs that are covered by carbon dioxide ice in winter but visible from orbit in summer. A new study posits that the spiral formed by wind erosion, exposing layer after layer of Martian geology.
The center of Mars’s polar cap is higher in the center than toward the edges, so katabatic winds — cold, dense flows beginning at high elevation — rush down from the pole. But because Mars spins, the Coriolis force causes those winds to flow in an anti-clockwise spiral. As those winds encounter depressions perpendicular to their path, they generate vortices that erode the depression. Eventually, a depression deepens, merges with other depressions, and forms a trough. According to this theory, the clockwise spiral of the troughs is a direct result of the katabatic winds flowing across them. Head over to Bad Astronomy or check out the original paper for more. (Image credit: ESA/DLR/FU Berlin/J. Cowart; research credit: J. Rodriguez et al.; via Bad Astronomy; submitted by Kam-Yung Soh)
July 14, 2021
Unusual Insects Taking Off
What do you do when you’re an insect researcher with a high-speed camera? Why, film all sorts of unusual insects from your backyard as they take off and fly! Here Dr. Adrian Smith of Ant Lab shows us a slew of insects that are not unusual for their rarity — you can probably find many of these in your own yard — but they are rarely seen in insect flight research. Like many of the species we’ve seen before, lots of these fliers use a figure-8 wingstroke to stay aloft. But one feature that really struck me as I watched was how amazingly flexible many of their wings were. For many of them, parts of their wings actually curl back on themselves during parts of the stroke. As engineers, our first instinct would be to avoid that kind of complexity, but I expect that it must give the insects some kind of benefit — otherwise nature would have eliminated it. (Image and video credit: Ant Lab/A. Smith; via Colossal)
July 13, 2021
How Frogs Block Unwanted Noise
In a crowded room, it can be hard to pick out the one conversation you want to hear. This so-called “cocktail party problem” is one animals have to contend with, too, when a noisy landscape can obscure the calls of potential mates. American green tree frogs have a clever solution to the problem: inflating their lungs to dampen out other frog species’ calls.
This method works because frogs have a direct anatomical connection between their lungs and their eardrums. Researchers found that when these frogs inflate their lungs, there’s a pronounced drop in their sensitivity to sound in the 1.4 – 2.2 kHz frequency band. That frequency range falls between the green tree frog’s peak mating call frequencies, but it coincides with the frequencies of other frogs living in the same regions. So rather than using their lungs to make themselves louder, these clever amphibians use them to make other frogs quieter! (Image credit: B. Gratwicke; research credit: N. Lee et al.; via Physics Today)
July 12, 2021
“Playing With Time”
The Macro Room team is back with this clever video that messes with our perception of time. I’d hate to give anything away here, so just go check it out! (Image and video credit: Macro Room)
July 9, 2021
When Rivers Break Their Banks
Rivers often change their course, but they do not always do so gradually. River avulsions are a bit like earthquakes — they happen suddenly and with disastrous potential. Researchers find that these sudden course changes happen when silt builds up in a river and reduces the amount of water it can carry. Eventually, the resistance to flow is large enough that the river bursts its banks in search of an easier route to the sea. That’s a deadly problem for the communities that live nearby and rely on the river’s sedimentation for their fertile farmland. But using small-scale models, scientists are beginning to unravel the physics behind avulsions, bringing hope that they can be predicted or even sustainably averted. (Video and image credit: Science)
July 8, 2021
Springtails Jump Off Water
Springtails are tiny hexapods often found near water, where they execute their superpower: backflipping off the water’s surface. When standing on the water, the springtail’s hydrophilic claws protrude beneath the water surface and give it traction. But its spring-loaded furcula is hydrophobic, so when it snaps down it strikes the water without breaking through. The impact propels the springtail upward and sets it spinning at an incredible rate — Smith saw up to 290 backflips a second! (Image and video credit: Ant Lab/A. Smith)
July 7, 2021