Part III of Vi Hart’s series on Spirals, Fibonacci, and Being a Plant
Category Archives: Other science
You've Got Some Explaining to Do
Electric Material in Mantle Could Explain Earth’s Rotation
Well, not really. The electric material could explain some of the small variations in the Earth’s rotation. Not quite the same thing.
Earth’s spin isn’t flawless. Geophysicists have discovered that the time it takes our planet to complete one rotation—the length of a day—fluctuates slightly over the course of months or years. They’ve also noticed extra swing in the predictable wobble of Earth’s axis of rotation, like the swaying of a spinning top. The variations are probably caused by the solid iron inner core, liquid metal outer core, and rocky mantle rotating at slightly different rates. Friction helps bring them into line, and the magnetic field of the outer core can pull on the metal inner core. But to really fit the observations, the core should also exert its magnetic tug on the mantle, says Bruce Buffett, an earth scientist at the University of California, Berkeley, who was not involved in the new study. This means that a layer of the mantle must be able to conduct electricity. But, he says, “the origin of the metallic layer remains an open question.”
How a Cat Really Works
Flight Artists
High-Speed Animal Flight Videos Show Hidden Aerial World
With good lighting and a little luck, amateur videographers can use inexpensive digital cameras to transform blurred flight into breathtaking glimpses of animal behavior.
In that spirit, a Dutch program called Vilegkunstenaars, or Flight Artists, sent high-speed video tools to amateurs around the world. The challenge: Capture nature in flight.
Over the course of a year, the contest drew 460 amateurs who uploaded more than 2,400 slow-motion video clips shot with their complimentary cameras.
I’m a tad envious of them. The prospect of having a professional-grade camera … (cue Homeresque power-drool)
Fire in the Hole!
NCBI ROFL: Farts: an underappreciated threat to astronauts
Intestinal bacteria form two gases, hydrogen (H2) and methane (CH4), that could constitute a fire hazard in a closed chamber.
Of Oscillators and Switches
Switches, Oscillators, Yeast Cells, Magnets, Earthquakes, Cancer Cells, Brains….
An “oscillator” in this context can mean a wide variety of things: runners on a track, quantum-mechanical systems, fireflies flashing, rhythms in cells. The main thing is that when left alone, oscillators repeat themselves in a predictable way, cycling through the same motions or energy flows or whatever. When they are allowed to interact (runners adjusting their pace to match others, for example), they can fall into sync with each other – assuming the interaction is strong enough.
I Can't Haz Gravity
Ohno, it's the Apollo Zone
Powerful Pixels: Mapping the “Apollo Zone”
The “Apollo Zone” Digital Image Mosaic (DIM) and Digital Terrain Model (DTM) maps cover about 18 percent of the lunar surface at a resolution of 98 feet (30 meters) per pixel. The maps are the result of three years of work by the Intelligent Robotics Group (IRG) at NASA Ames, and are available to view through the NASA Lunar Mapping and Modeling Portal (LMMP) and Google Moon feature in Google Earth.
I couldn’t get the flash player option (LMMP site) to work, but I was able to view it in Google Earth.
What the Angels Share
The Mystery of the Canadian Whiskey Fungus
Leave fruit juice on its own for a few days or weeks and yeast—a type of fungus—will appear as if by magic. In one of nature’s great miracles, yeast eats sugar and excretes carbon dioxide and ethanol, the chemical that makes booze boozy. That’s fermentation.
If fermentation is a miracle of nature, then distillation is a miracle of science. Heat a fermented liquid and the lighter, more volatile chemical components—alcohols, ketones, esters, and so on—evaporate and separate from the heavier ones (like water). That vapor, cooled and condensed into a liquid, is a spirit. Do it to wine, you get brandy; beer, you get whiskey. Distill anything enough times and you get vodka. When it’s executed right, the process concentrates a remarkable array of aromatic and flavorful chemicals.
Interlude
Four Mile Run, from about a month ago, on a nice warm day while I was geocaching. I had climbed down to the water and upstream a ways in a vain search and stopped to admire the scenery.
I also spied this. I’m guessing metamorphic, which might be a gneiss guess, but I don’t know schist from shinola.
When I decided to leave I forgot Spengler’s advice and I crossed the stream. Turns out wet rocks are really slippery because of the slime on them (curse you, low coefficient of friction! Mu-uuuuuuuu!). I fell in (only up to mid-shin, and it was a mild day, so no big deal) but also banged my elbow, which took a week or so to un-stiffen.