Tag Archives: fluid dynamics

Ice Volcano on Ceres

Scientists studying dwarf planet Ceres have found that a  13,000-foot volcano there arose not from silicic magma, but from muddy, salty ice that rose to the ~160 K surface and quick-froze like Smucker’s® Magic Shell.

Finding such a dramatic cryovolcanic process this close to the sun – in the inner asteroid belt between Mars and Jupiter – is unusual, and bolsters the idea that Ceres might have originated in the outer solar system. It also lends credence to the notion that asteroids and comets might be more closely related than once thought.

Read/listen to  my full story at KJZZ’s Arizona Science Desk:
13,000-Foot Mountain On Dwarf Planet Ceres May Be An Ice Volcano

Blood Will Tell: A Blood Spatter Analysis Update

Eduard Piotrowski of Poland’s University of Krakow published the first major blood spatter study in 1895, but its impact was limited to a few inventive European sleuths like German chemist Paul Jeserich and French forensic scientist Victor Balthazard. The American legal system did not adopt spatter analysis as evidence until the landmark case of State of Ohio v. Samuel Sheppard, and the field did not truly take off until the 1970s, after forensics expert Herbert MacDonell published his influential Flight Characteristics of Human Blood and Stain Patterns.

Blood spatter analysis has undergone major refinements in methods and language since then, including a recent and growing shift toward incorporating computers. I discuss several of these shifts in my 2015 update of Shanna Freeman’s 2007 article:

How Bloodstain Pattern Analysis Works

Ramjets: Making Mock of Mach

1946 ramjet test. Image courtesy NASA.

The faster you go, the less inclined the air becomes to get out of your way. This simple fact, which stood for years as an impediment to breaking the sound barrier, can also be ingeniously harnessed to create an engine capable of zipping along at supersonic speeds without the fuel weight required by rockets.

In this article, I trace the history, science and engineering behind this revolutionary “flying stovepipe,” from its theoretical birth during the biplane era to its modern military and commercial offshoots. By the time we’re done, you’ll understand…

How Ramjets Work

Going the Extra Mile (on the Same Tank of Gas)

Photo of a gas price sign.
Photo by Ildar Sagdejev

Call it ecodriving, hypermiling or plain old frugality, people today are trying every trick they can think of to wring a few extra miles from a drop of gas. Unfortunately, most fuel-saving tips range from the dubious to the downright dimwitted. Even the ones that work — such as making only right turns — veer into the ridiculous. In this Top 5 list, I’ve separated the classics from the clunkers and saved you the trouble of doing your own Mythbusters episode. Read on to discover….

Everyday Driving Tips to Save Fuel

Weighing in on Digital Scales

A truck in Tanzania drives onto a truck scale
A truck scale in Tanzania. Photo by Jan Hoffmann.

Whether they are weighing train cars, big rigs or vegetables in your local grocery, scales are the engines that drive global commerce. Without them, there could be no trade, and laboratories and pharmaceutical companies would have to dream up other ways to assay, mete and dose. Yet most of us are oblivious to the physical laws and clever engineering that go into these pivotal devices. It’s time to weigh in on…

How Digital Scales Work