Category Archives: Chemistry

Is Progress Outpacing Precaution? Experts Weigh In

Illustration by An Arres.

No one expects the machinery of progress to roll backwards, but sometimes it seems that no one is watching the speedometer (or manning the brakes, assuming any exist).  Is this a fair assessment? If so, should we be worried — and what can we do about it?

In this feature, experts on technology, risk, science, policy and neuroscience discuss risk, innovation and how our values affect our conceptions of both.

Read/listen to my full story at KJZZ’s Arizona Science Desk:
ASU Experts Weigh the Risks of Innovation

The Foggy Future of Refrigerants

Freon tanks await recycling. Image courtesy U.S. Environmental Protection Agency.

Stable, nontoxic refrigerants changed the world, transforming food storage, expanding Sun Belt populations, even helping early movie theaters succeed. But they also wrecked the ozone layer — Earth’s shield against harmful ultraviolet radiation.

Today, as stockpiles dwindle — and prices rise — due to phase-outs set by the Montreal Protocols 30 years ago,  the future of Freon and its successors remains in doubt.

Read/listen to my full story at KJZZ’s Arizona Science Desk:
As Stockpiles Dwindle, Freon Prices Rise

A GRaND Discovery: Dwarf Planet Ceres is Well-Stocked With Water


After 4 billion years, the dwarf planet Ceres is still carrying a surprising amount of water weight — as much as 30 percent.

The finding, which was published in the Jan. 6 edition of the journal Science, is consistent with earlier models, and provides valuable clues to how Ceres formed.

Read/listen to my full story at KJZZ’s Arizona Science Desk:
Dwarf Planet Ceres Up To 30 Percent Water

After 85 Years, Physicists Confirm Weyl Particle

Photo portrait of Hermann Weyl.
Hermann Weyl. Photo courtesy ETH-Bibliothek Zurich.

In 1928, the equations of British physicist Paul Dirac helped to describe the workings of the subatomic particles known as fermions. Within a year, other theorists – including a contemporary and schoolmate of Einstein’s named Hermann Weyl – had come up with solutions to Dirac’s equations that meant two other, quite odd types of fermions might also exist.

Proving them right would take some time, and Weyl’s quasiparticle assumed a kind of legendary status until 2015, when three separate teams confirmed its existence (my article says two, but a third popped up after I wrote it). Read on to find out more about this “ghost particle” and how it could transform electronics.

Meet Weyl, the Massless Particle That Could Upend Electronics

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