Ever see the shockwave of a volcano erupting? Phil and Linda McNamara did—and videotaped it—while vacationing in Papua New Guinea. Hearing that nearby Mount Tavurvur was erupting, they hopped a boat for a closer look, and…wow. You can see the shockwave traveling down the slope of the volcano, and immediately afterward you’ll see it rearranging air molecules above the ash plume. The sudden air compression wrings out water vapor and creates temporary clouds in an expanding circle. Several seconds later, that expanding circle arrives at the boat.
Note: if you’re wearing headphones while watching this, I’d advise not having the volume up too high. The sonic boom when the shockwave hits the boat is substantial. Also, I got a huge laugh out of the man who, after the boom, exlaims, “Holy ssss…smokin’ Toledos!”
In an entirely different branch of science, here is my vote for Blog Headline of the Week:
SCIENCE HAS DISCOVERED HOW TO BAKE THE PERFECT CHOCOLATE CHIP COOKIE, WORLD PEACE TO BE ANNOUNCED SOON
As one who is constantly in search of the perfect chocolate chip cookie (and reasonably convinced that perfection has indeed been achieved, at least with my oatmeal peanut butter chocolate chip cookie recipe), I already knew about the differences these little changes can make. But I’ve never seen such an awesome visual illustration:
That picture neatly sums up the pages and pages of text I’ve read on the topic. (Because yes, some things are worth that kind of devotion.)
The Ozy post has a rundown of which changes do what, if you just want a quick guide. But if you’re in search of more detail and an actual recipe, go to Handle the Heat and lose yourself in cookie research.
Shifting gears again, did you know that the mystery of Death Valley’s traveling rocks has finally been solved?
The (in)famous Racetrack Playa rocks keep moving when nobody’s looking. Furrows behind them are ample evidence of their travels, and many of them move in parallel tracks, including turns. But until now nobody knew how.
(Photo by Arno Gourdol)
Ars Technica has a nice write-up of the mechanics behind the traveling rocks. Conditions have to be just right, and it’s a rare event, but it’s no longer a total mystery. Plus it’s always fun when everyone’s best guesses turn out to be wrong. Most scientists had assumed that forces of great strength had to be at work, including gale-force winds in nasty, frozen weather. Nope, just a bit of a breeze, thanks—plus some water, sunshine, and thin sheets of ice.
The research team that solved this mystery has put together a great explanatory video, in which they produce a smoking gun: actual footage of a rock caught in the act.
Okay, one last video, but it’s only two minutes long. It’s a short film with an ending you will not expect.