Open-Sourcing The Lisa, Mac’s Bigger Sister

Forty years ago, on January 19th of 1983, Apple released the Lisa, which was in many ways a revolutionary system. On January 19th of 2023, to celebrate the system’s 40th birthday, the Computer History Museum released the source code for Lisa OS version 3.1 under the Apple Academic License Agreement. Written in Pascal, the source includes over 1,300 source files, covering the OS itself, the Lisa Toolkit development system and a number of applications. The questions one might ask at this point include what the Apple Lisa even is, and why it was such an important system in computer history.

This especially in light of the terrible flop that the Lisa turned out to be, with only 10,000 units sold over two years. Part of this failure was definitely due to the introductory price, that was set at $9,995 (over $27,000 in 2021 dollars). Although it featured an OS with memory protection, despite the lack of an MMU on the Motorola 68k, among other advanced features that placed it well beyond other desktop computers of the time, it got quickly crushed in the market by Apple’s MacIntosh, even after successive Lisa successor releases that sought to address its shortcomings.

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Broken Genes And Scrambled Proteins: How Radiation Causes Biological Damage

If decades of cheesy sci-fi and pop culture have taught us anything, it’s that radiation is a universally bad thing that invariably causes the genetic mutations that gifted us with everything from Godzilla to Blinky the Three-Eyed Fish. There’s a kernel of truth there, of course. One only needs to look at pictures of what happened to Hiroshima survivors or the first responders at Chernobyl to see extreme examples of what radiation can do to living tissues.

But as is usually the case, a closer look at examples a little further away from the extremes can be instructive, and tell us a little more about how radiation, both ionizing and non-ionizing, can cause damage to biochemical structures and processes. Doing so reveals that, while DNA is certainly in the crosshairs for damage by radiation, it’s not the only target — proteins, carbohydrates, and even the lipids that form the membranes within cells are subject to radiation damage, both directly and indirectly. And the mechanisms underlying all of this end up revealing a lot about how life evolved, as well as being interesting in their own right.

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NASA Lunar Probe Finds Out It’s Not Easy Being Green

If you’re a space fan, these are very exciting days. There’s so much happening overhead that sometimes it can be difficult to keep up with the latest news. Artemis I just got back from the Moon, the International Space Station crew are dealing with a busted Soyuz, SpaceX is making incredible progress with their Starship architecture, CubeSats are being flung all over the solar system, and it seems like every month a new company is unveiling their own commercially-developed launch vehicle.

Lunar Flashlight

So with everything going on, we wouldn’t be surprised if you haven’t heard about NASA’s Lunar Flashlight mission. The briefcase-sized spacecraft was launched aboard a special “rideshare” flight of SpaceX’s Falcon 9 rocket back on December 11th — tagging along with two other craft heading to our nearest celestial neighbor, the Japanese Hakuto-R lander, and a small rover developed by the United Arab Emirates. There was a time when a launch like that would have been big news, but being that it was only the second of seven launches that SpaceX performed in December alone, it didn’t make many headlines.

But recently, that’s started to change. There’s a growing buzz around Lunar Flashlight, though unfortunately, not for the reasons we’d usually hope. It seems the diminutive explorer has run into some trouble with its cutting-edge “green” propellant system, and unless the issue can be resolved soon, the promising mission could come to an end before it even had a chance to start.

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Wizards Slay The Dragon That Lays The Golden Egg

Hail, and well met adventurers! There’s rumors of dark dealings, and mysterious machinations from that group of Western mystics, Wizards of the Coast (WotC). If this pernicious plot is allowed to succeed, a wave of darkness will spread over this land of Open Source gaming, the vile legal fog sticking to and tainting everything it touches. Our quest today is to determine the truth of these words, and determine a defense for the world of open gaming, and indeed perhaps the entire free world! Beware, the following adventure will delve into the bleak magic of licensing, contract law, and litigation.

Ah, Dungeons and Dragons. The original creation of Gary Gygax, refined by countless others, this table-top role-playing game has brought entertainment and much more to millions of players for years. In 2000, WotC made a decision that opened the mechanics of that universe to everyone. The 3rd Edition of Dungeons and Dragons was released under the Open Gaming License, a very intentional port of Open Source licensing to table-top gaming — obviously inspired by the GNU Public License. Ryan Dancey was one of the drivers behind the new approach, and made this statement about it:

I think there’s a very, very strong business case that can be made for the idea of embracing the ideas at the heart of the Open Source movement and finding a place for them in gaming. […] One of my fundamental arguments is that by pursuing the Open Gaming concept, Wizards can establish a clear policy on what it will, and will not allow people to do with its copyrighted materials. Just that alone should spur a huge surge in independent content creation that will feed into the D&D network.

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The Intricacies Of Creating Fuel For Nuclear Reactors

All nuclear fission power reactors run on fuel containing uranium and other isotopes, but fueling a nuclear reactor is a lot more complicated than driving up to them with a dump truck filled with uranium ore and filling ‘er up. Although nuclear fission is simple enough that it can occur without human intervention as happened for example at the Oklo natural fission reactors, within a commercial reactor the goal is to create a nuclear chain reaction that targets a high burn-up (fission rate), with an as constant as possible release of energy.

Each different fission reactor design makes a number of assumptions about the fuel rods that are inserted into it. These assumptions can be about the enrichment ratio of the fissile isotopes like U-235, the density of individual fuel pellets, the spacing between the fuel rods containing these pellets, the configuration of said fuel rods along with any control, moderator and other elements. and so on.

Today’s light water reactors, heavy water reactors, fast neutron reactors, high temperature reactors and kin all have their own fuel preferences as a result, with high-assay low-enriched (HALEU) fuel being the new hot thing for new reactor designs. Let’s take a look at what goes into these fuel recipes.

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Ask Hackaday: What’s Your Worst Repair Win?

Like many of you, I’ve become the designated “fix-it” person for my family and friends. While it can be a lot of work — I just finished an oil change that required me to lay in a cold, wet driveway and I can’t mention in polite company the substances I was bathed in while fixing a clogged pipe last week  — I generally relish my role. I enjoy solving problems, I love working with my hands and my head, and who doesn’t like saving money and time?

But for me, the best part of being the fix-it guy is the satisfaction that comes from doing something others can’t do. I find this especially true with automotive repairs, which conventional wisdom says is strictly the province of factory-trained experts. A little bit of a hero complex, perhaps? Absolutely! After all, I don’t get paid for my repairs, so I’ve got to get a little something for the effort.

This is why a recent pair of unrelated fixes left me feeling thoroughly unsatisfied. Neither of these jobs was a clear win, at least in terms of getting the rush of being able to do something that nobody else could. At best, these were qualified wins, which both still left me feeling a little defeated. And that got me thinking that I’m probably not the only one who has had marginal repair wins like these.

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Excuse Me, Your Tie Is Unzipped

If you ask your typical handyperson what’s the one thing you need to fix most things, the answer might very well be duct tape. But second place — and first place in some circles — would have to be zip ties. These little wonders are everywhere if you look for them. But they are a relatively recent invention and haven’t always had the form they have today.

The original zip tie wasn’t called a zip tie or even a cable tie. In 1958 they were called Ty-Raps and produced by a company called Thomas and Betts. Originally meant to improve aircraft wiring harnesses, they found their way into various electronic equipment and packaging uses. But they’ve also become helpful in very unusual places too. A policeman trying to round up rioters would have problems carrying more than a few conventional handcuffs. But flexible cuffs based on zip ties are lightweight and easy to carry. Colon surgeons sometimes use a modified form of zip tie during procedures.

History

Maurus Logan worked for the Thomas and Betts company. In 1956, he was touring an aircraft manufacturing plant. Observing a wiring harness being put together on a nail board, similar to how car harnesses are made, he noted that the cables were bundled with waxed twine or nylon cord. A technician had to tie knots in the cord, sometimes cutting their fingers and often developing calluses. In addition, the twine was prone to fungal growth, requiring special treatment.

Logan kept turning the problem over in his mind and tried various approaches. By 1958, he had a patent for the Ty-Rap. The tie was lightweight, easy to install, easy to remove, and inexpensive.

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