Numlock News: May 20, 2021 • Supernova, Ocean Meat, Jaguars

By Walt Hickey

This Saturday is Numlock’s third anniversary! Annual subscriptions are discounted 25 percent all week and there’s more to come.

Get 25% off for 1 year


The rush to electric vehicles largely skipped aviation, as the math is just difficult to work out from a weight perspective. Rechargeable lithium-ion batteries put out 9 megajoules per kilogram of weight, which is great for vehicles but compared to the 40 megajoules per kilogram of jet fuel, it’s not all that great. All’s not lost in the quest to decarbonize planes, though: hydrogen provides 140 megajoules per kilogram, and fuel cells are being tried out on light and regional aircraft to improving economic performance: fuel cells used by Universal Hydrogen and ZeroAvia are performing at $40 per kilowatt, down 68 percent since 2006.

Jon Sindreau, The Wall Street Journal


Researchers with a number of conservation groups are proposing the re-introduction of the jaguar into the southwestern United States, pointing to a 31,800 square mile region that could support 90 to 150 jaguars. Reintroducing the cats will have its perks, helping to restore an ecosystem and giving the animals a boost in a region largely cutoff from their historic range by a wall. I am on record being largely in favor of reintroducing animals to their ancestral range, my New York City mayor ballot will be decided based entirely on who responds to my “release a pack of wolves in Manhattan” change dot org petition the soonest.

Susan Montoya Bryan, The Associated Press

Diagnose on Contact

A paper published in the Journal of Agricultural and Food Chemistry found a new application of the MasSpec Pen, a medical device used to help diagnose tumors on contact: identifying the species of a give fish filet. This is actually a solid skill, as testing on five samples found it took less than 15 seconds to identify the species, which is vastly faster than the PCR testing used today to identify the catch of the day. Mislabeled seafood is a big problem, with one 2019 analysis finding about 8 percent of seafood products are mislabeled. Finally, the American people can figure out what exact Arby’s was selling when they hawked the ambiguously named “Ocean Meat.”

Jen Monnier, Scientific American

Rare Earths

Rare earth permanent magnets maintain their magnetic properties even after being exposed to a magnetic field, which makes them very useful in industrial and technical applications. China produced 87 percent of the world’s rare earth permanent magnets in 2018, with most of the rest produced by Japan. Beyond the raw materials, lots of the appeal is lower costs of manufacturing the magnets, as it’s 20 percent cheaper to make a rare earth magnet in China than in Europe. The main risk to China’s dominance in the space is that Japan’s firms control a lot of the intellectual property and patents in the rare earth space, with Hitatchi Metals alone holding over 600 patents for the NdFeB magnets and licensing them out to Chinese magnet makers.

Mary Hui, Quartz

Get 25% off for 1 year


A new study pegs the number of animals that can laugh at a minimum of 65, mostly primates but also things like birds. As described in the study, laughter was sought to be any vocalization made during play, which emerges so that animals can roughhouse without triggering a genuine fight response. Not all of these sound like human laughter; Rocky Mountain elks make a squealing sound, the degu kind of purrs, Seth Rogens do sort of a weird snort thing that sounds fun, and dogs pant in a unique way. Incidentally, the laughter sound from hyenas isn’t a “laugh” response, it’s actually really aggressive and is best understood less as chuckling and more as Joe Pesci in Goodfellas asking if they think he’s funny.

Doug Johnson, Ars Technica


Scientists found some small-batch artisanal freshly pressed plutonium-244 atoms at the bottom of the Pacific Ocean, debris that is believed to be extraterrestrial in origin according to the report published in Science. The rocks were hauled up by a Japanese oil exploration company and passed along to the researchers. The findings are interesting because the hundreds of atoms of plutonium-244, which doesn’t naturally occur on Earth. Based on this and other research, the culprit appears to be not one, but two exploding stars, one about 3 million years ago that sent a wave of radioactive iron and another 6 million years ago that dropped another wave. This is excellent news because I know a pattern when I see one, and I think this one would work really well as a Dwayne Johnson-helmed, Roland Emmerich-inspired disaster movie — hit me up Hollywood.

Nell Greenfieldboyce, NPR

9 to 5

A new study from the World Health Organization found that people working more than 55 hours each week face significant health risks, facing a 35 percent higher risk of stroke and a 17 percent higher risk of death from heart disease compared to people working only 35 to 40 hours per week. This is a lot of people: in 2016, the WHO estimated, 488 million people worked such long hours.

Bill Chappell, NPR

Get 25% off for 1 year

Thanks to the paid subscribers to Numlock News who make this possible. Subscribers guarantee this stays ad-free, and get a special Sunday edition. Consider becoming a full subscriber today.

The best way to reach new readers is word of mouth. If you click THIS LINKin your inbox, it’ll create an easy-to-send pre-written email you can just fire off to some friends.

Send links to me on Twitter at @WaltHickey or email me with numbers, tips, or feedback at Send corrections or typos to the copy desk at

Check out the Numlock Book Club and Numlock award season supplement.

2021 Sunday subscriber editions: Carbon Credits · Money in Politics · Local News · Oscar Upsets · Sneakers · Post-pandemic Cities · Facebook AI · Fireflies · Vehicle Safety ·

Climate Codes · Figure Skating · True Believer · Apprentices · Sports Polls · Pipeline · Wattpad · The Nib · Driven
2020 Sunday editions: 2020 · Sibling Rivalries · Crosswords · Bleak Friday · Prop 22 · NCAA · Guitars · Fumble Dimension ·
2020 Sunday Edition Archive
2019 Sunday Edition Archive
2018 Sunday Edition Archive