Since the widespread manufacture of plastics began in earnest in the early 1950s, plastic pollution in the environment has become a major global problem. Nowhere is this more evident than the Great Pacific Garbage Patch. A large ocean gyre that has become a swirling vortex full of slowly decaying plastic trash, it has become a primary target for ocean cleanup campaigns in recent years.
However, plastic just doesn’t magically appear in the middle of the ocean by magic. The vast majority of plastic in the ocean first passes through river systems around the globe. Thanks to new research, efforts are now beginning to turn to tackling the issue of plastic pollution before it gets out to the broader ocean, where it can be even harder to clean up. Continue reading “Targeting Rivers To Keep Plastic Pollution Out Of The Ocean”→
The simplest ideas can be the ones that change the world. For Otis Boykin, it was a new way to make wirewound precision resistors. Just like that, he altered the course of electronics with his ideas about what a resistor could be. Now his inventions are in everything from household appliances and electronics to missile guidance computers.
While we like to geek out about developments in resistor tech, Otis’ most widely notable contribution to electronics is the control unit he designed for pacemakers, which regulate a person’s heartbeat. Pacemakers are a real-time clock for humans, and he made them more precise than ever.
Street Smarts and Book Smarts
Otis Frank Boykin was born August 29th, 1920 in Dallas, Texas to Sarah and Walter Boykin. Otis’ father was a carpenter who later became a preacher. His mother Sarah was a maid, and she died of heart failure when Otis was only a year old.
Later this month, people who use GitHub may find themselves suddenly getting an error message while trying to authenticate against the GitHub API or perform actions on a GitHub repository with a username and password. The reason for this is the removal of this authentication option by GitHub, with a few ‘brown-out’ periods involving the rejection of passwords to give people warning of this fact.
This change was originally announced by GitHub in November of 2019, had a deprecation timeline assigned in February of 2020 and another blog update in July repeating the information. As noted there, only GitHub Enterprise Server remains unaffected for now. For everyone else, as of November 13th, 2020, in order to use GitHub services, the use of an OAuth token, personal token or SSH key is required.
While this is likely to affect a fair number of people who are using GitHub’s REST API and repositories, perhaps the more interesting question here is whether this is merely the beginning of a larger transformation away from username and password logins in services.
While early prototypes for SpaceX’s Starship have been exploding fairly regularly at the company’s Texas test facility, the overall program has been moving forward at a terrific pace. The towering spacecraft, which CEO Elon Musk believes will be the key to building a sustainable human colony on Mars, has gone from CGI rendering to flight hardware in just a few short years. That’s fast even by conventional rocket terms, but then, there’s little about Starship that anyone would dare call conventional.
An early Starship prototype being assembled.
Nearly every component of the deep space vehicle is either a technological leap forward or a deviation from the norm. Its revolutionary full-flow staged combustion engines, the first of their kind to ever fly, are so complex that the rest of the aerospace industry gave up trying to build them decades ago. To support rapid reusability, Starship’s sleek fuselage abandons finicky carbon fiber for much hardier (and heavier) stainless steel; a material that hasn’t been used to build a rocket since the dawn of the Space Age.
Then there’s the sheer size of it: when Starship is mounted atop its matching Super Heavy booster, it will be taller and heavier than both the iconic Saturn V and NASA’s upcoming Space Launch System. At liftoff the booster’s 31 Raptor engines will produce an incredible 16,000,000 pounds of thrust, unleashing a fearsome pressure wave on the ground that would literally be fatal for anyone who got too close.
Which leads to an interesting question: where could you safely launch (and land) such a massive rocket? Even under ideal circumstances you would need to keep people several kilometers away from the pad, but what if the worst should happen? It’s one thing if a single-engine prototype goes up in flames, but should a fully fueled Starship stack explode on the pad, the resulting fireball would have the equivalent energy of several kilotons of TNT.
Thanks to the stream of consciousness that Elon often unloads on Twitter, we might have our answer. While responding to a comment about past efforts to launch orbital rockets from the ocean, he casually mentioned that Starship would likely operate from floating spaceports once it started flying regularly:
While history cautions us against looking too deeply into Elon’s social media comments, the potential advantages to launching Starship from the ocean are a bit too much to dismiss out of hand. Especially since it’s a proven technology: the Zenit rocket he references made more than 30 successful orbital launches from its unique floating pad.
Thermites are a double-edged sword. Packing a tremendous energy density, and eager to produce tremendous heat when ignited, thermite is great for welding train tracks. But sometimes you might be looking for a little more finesse. A new approach to 3D printing thermites might just be able to tame the beast.
Most of us do our soldering while sitting safely indoors in a comfortable climate. The biggest dangers we’re likely to face are burnt fingertips, forgetting the heat shrink, or accidentally releasing the smoke monster. But outside of our homes and workshops, there’s a lot of extreme joining of metals going on. No matter where it’s done, welding and brazing in the field requires a lot of equipment, some of which is unwieldy and even more difficult to move around in harsh conditions.
Welding railroad tracks with thermite. Image via YouTube
The utility of brazing is limited by all the complex scaffolding of hardware required to support it. This limiting factor and the discovery of thermite led to exothermic welding, which uses an energetic material to provide enough heat to melt a filler metal and join the pieces. Energetic materials can store a lot of chemical energy and forcefully release it in a short period of time.
Thermites are made of metal oxide and metal powder, often iron oxide and aluminium. When ignited by a source of high heat, thermite compounds undergo an exothermic reduction-oxidation (redox) reaction as the aluminium reduces the number of electrons in the iron oxide atoms. More heat makes the reaction run faster, generating more heat, and so on. The result is molten iron and aluminium oxide slag.
It’s a common enough Hollywood trope that we’ve all probably seen it: the general, chest bespangled with medals and ribbons, gazes at a big screen swarming with the phosphor traces of incoming ICBMs, defeatedly picks up the phone and somberly intones, “Get me the president.” We’re left on the edge of our seats as we ponder what it must be like to have to deliver the bad news to the boss, knowing full well that his response will literally light the world on fire.
Scenes like that work because we suspect that real-life versions of it probably played out dozens of times during the Cold War, and likely once or twice since its official conclusion. Such scenes also play into our suspicion that military and political leaders have at their disposal technologies that are vastly superior to what’s available to consumers, chief among them being special communications networks that provide capabilities we could only have dreamed of back then.
As it turns out, the US military did indeed have different and better telephone capabilities during the Cold War than those enjoyed by their civilian counterparts. But as we shall see, the increased capabilities of the network that came to be known as AUTOVON didn’t come so much from better technology, but more from duplicating the existing public switched-telephone network and using good engineering principles, a lot of concrete, and a dash of paranoia to protect it.
The SD card first burst onto the scene in 1999, with cards boasting storage capacities up to 64 MB hitting store shelves in the first quarter of 2000. Over the years, sizes slowly crept up as our thirst for more storage continued to grow. Fast forward to today, and the biggest microSD cards pack up to a whopping 1 TB into a package smaller than the average postage stamp.
However, getting to this point has required many subtle changes over the years. This can cause havoc for users trying to use the latest cards in older devices. To find out why, we need to take a look under the hood at how SD cards deal with storage capacity. Continue reading “Size Does Matter When It Comes To SD Cards”→
