Hackaday Links: July 23, 2023

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It may be midwinter in Perth, but people still go to the beach there, which led to the surprising discovery earlier this week of what appears to be a large hunk of space debris. Local authorities quickly responded to reports of a barnacle-encrusted 2.5-m by 3-m tank-like object on the beach. The object, which has clearly seen better days, was described as being made of metal and a “wood-like material,” which on casual inspection is clearly a composite material like Kevlar fibers in some sort of resin. Local fire officials teamed up with forensic chemists to analyze the object for contamination; finding none, West Australia police cordoned off the device to keep the curious at bay. In an apparently acute case of not knowing how the Internet works, they also “urge[d] everyone to refrain from drawing conclusions” online, which of course sent the virtual sleuths into overdrive. An r/whatisthisthing thread makes a good case for it being part of the remains of the third stage of an Indian Polar Satellite Launch Vehicle (PSLV); reentry of these boosters is generally targeted at the East Indian Ocean for safe disposal, but wind and weather seem to have brought this artifact back from the depths.

Also in possible space junk news, a woman in France joined a very select club by being struck with apparent meteor fragments during a sunrise coffee break. The woman describes the encounter, which has about a one in 20,000,000,000,000 chance of occurring, as a rebound from a meteor hitting a nearby roof. The shrapnel hit her in the ribs, whereupon she has the admirable presence of mind to go collect as much of the projectile’s remains as possible. Thinking it to be a piece of cement at first, she took it to a friend in the roofing trade for an opinion. The roofer realized it was something else entirely, so the woman took it to a geologist who identified it as an iron/silicon meteor. But not so fast — others have taken a look at photos of the object and concluded that it couldn’t possibly be a meteor. We’ve got to admit that the doubters seem to have a point, especially since it has always been our impression that meteors are incredibly dense, and seem more like something that would punch a hole through a roof rather than breaking into pieces while landing upon it.

In the world of high-availability servers, 2,700 hours of uptime might not sound like much. But when your web server is a nearly 40-year-old IBM-PCjr that has been running continuously since March 2023, it’s something very much worth celebrating. The beige box — complete with a period-correct embossed tape label — contains a few things that wouldn’t have been seen in the 1980s, like an IDE adapter and a 240-GB SATA SSD and a whopping 768-kB of RAM, which would have cost a small fortune back then. But the motherboard still sports the 4.77-MHz V20 CPU, and the OS is PC-DOS 5.02 — the BIOS date is June of 1983! — so even with a few expansions, this is very much a machine of its time. We almost hate to call attention to the machine and its current status page, lest it receive too much Hackaday love and spoil the uptime. So tread carefully, please.

The Oppenheimer hype train is rolling right along, with movie-related content pouring into our news feeds on a daily basis. The attempt to coerce us into shelling out money to see this particular flick is wasted on us; we made up our minds to see this one in the theater a long time ago. But the exertions of the “Oppen-hypers” haven’t been for naught, as we’ve gleaned some interesting Manhattan Project content from the noise. One of the most interesting is this video which takes a deeper dive into the whole “we could have set the atmosphere on fire” worry that Oppenheimer and his team had before the Trinity test. We’d heard plenty about that, but never the physics or the math, which turn out to be pretty fascinating. Basically, the fear was that the heat of the plutonium implosion bomb would cause atmospheric nitrogen to fuse into magnesium and cause a thermonuclear chain reaction that would turn the world into a cinder. It didn’t turn out that way, of course, but the math shows that the margin for error was way, way too close for comfort.

And finally, a far less apocalyptic video for your weekend viewing pleasure: A look into the sharpness of obsidian flakes. We’d always heard that the volcanic glass could be flaked into edges that rival the finest surgical steel, and allowed Stone Age cultures to develop some surprisingly advanced cutting technologies. The video compares knapped flint and obsidian to modern steel edges — both a commercial razor blade and a fine double-bevel-sharpened woodworking chisel. Using a micrometer to advance the edges into a single human hair under a microscope, it turns out that while natural materials are certainly sharp, they’re no match for the toughness of steel edges. Which begs the question: Why is obsidian used as a cutting edge in modern specialty surgical scalpels? If an obsidian edge nicks when forced against a human hair, how does it stand up against even the tenderest of skin?



Hackaday Links: July 23, 2023
Source: Manila Flash Report

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