Author: Dan Maloney

3357 Articles

Psst… Got A Second? Here Are The 2025 One-Hertz Challenge Winners

September 5, 2025 by 20 Comments

Even with teachers with names like Kirchhoff and Helmholtz, old Heinrich Hertz himself likely didn’t have the slightest idea that his name would one day become an SI unit. Less likely still would have been the idea that Hackaday would honor him with the 2025 One-Hertz Challenge.

The challenge was deliberately — dare we say, fiendishly? — simple: Do something, anything, but do it once a second. Flash a light, ring a bell, click a relay, or even spam comments on a website other than Hackaday; anything at all, but do it at as close to one Hertz as possible. These are our favorite kinds of contests, because the simplicity affords a huge canvas for the creative mind to paint upon while still providing an interesting technical constraint that’s just difficult enough to make things spicy.

And boy, did you respond! We’ve received over a hundred entries since we announced the contest back in June, meaning that many of you spent 4,662,000 seconds of your summer (at least those of you above the equator) rising to the challenge. The time was well spent, with projects that pushed the limits of what we even expected.

While we loved ’em all, we had to winnow them down to the top three, each of which receives a $150 gift certificate from our sponsor, DigiKey. Let’s take a look at them, along with our favorite runners-up.

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Field Guide To North American Crop Irrigation

September 3, 2025 by 26 Comments

Human existence boils down to one brutal fact: however much food you have, it’s enough to last for the rest of your life. Finding your next meal has always been the central organizing fact of life, and whether that meal came from an unfortunate gazelle or the local supermarket is irrelevant. The clock starts ticking once you finish a meal, and if you can’t find the next one in time, you’ve got trouble.

Working around this problem is basically why humans invented agriculture. As tasty as they may be, gazelles don’t scale well to large populations, but it’s relatively easy to grow a lot of plants that are just as tasty and don’t try to run away when you go to cut them down. The problem is that growing a lot of plants requires a lot of water, often more than Mother Nature provides in the form of rain. And that’s where artificial irrigation comes into the picture.

We’ve been watering our crops with water diverted from rivers, lakes, and wells for almost as long as we’ve been doing agriculture, but it’s only within the last 100 years or so that we’ve reached a scale where massive pieces of infrastructure are needed to get the job done. Above-ground irrigation is a big business, both in terms of the investment farmers have to make in the equipment and the scale of the fields it turns from dry, dusty patches of dirt into verdant crops that feed the world. Here’s a look at the engineering behind some of the more prevalent methods of above-ground irrigation here in North America.

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Hackaday Links: August 31, 2025

August 31, 2025 by 8 Comments

Back in March, we covered the story of Davis Lu, a disgruntled coder who programmed a logic bomb into his employers’ systems. His code was malicious in the extreme, designed as it was to regularly search for his Active Directory entry and fire off a series of crippling commands should it appear he had been fired. His 2019 sacking and subsequent deletion of his AD profile triggered the job, wreaking havoc on servers and causing general mayhem. Whatever satisfaction Lu drew from that must have been fleeting, because he was quickly arrested, brought to trial in federal court, and found guilty of causing intentional damage to protected computer systems.

Lu faced a decade in federal prison for the stunt, but at his sentencing last week, he got four years behind bars followed by three years of supervised release. That’s still a pretty stiff sentence, and depending on where he serves it, things might not go well for him. Uber-geek Chris Boden has some experience in the federal prison system as a result of some cryptocurrency malfeasance; his video on his time in lockup is probably something Mr. Lu should watch while he can. Honestly, we feel bad for him in a way because we’ve been there; we certainly toyed with the logic bomb idea when we were coding for a living, without actually ever doing it. Maybe he thought it would just get treated as a prank, but that was probably never in the cards; as we’re fond of telling our kids, the world just doesn’t have a sense of humor anymore.

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Where There Is No Down: Measuring Liquid Levels In Space

August 26, 2025 by 40 Comments

As you can probably imagine, we get tips on a lot of really interesting projects here at Hackaday. Most are pretty serious, at least insofar as they aim to solve a specific problem in some new and clever way. Some, though, are a little more lighthearted, such as a fun project that came across the tips line back in May. Charmingly dubbed “pISSStream,” the project taps into NASA’s official public telemetry stream for the International Space Station to display the current level of the urine tank on the Space Station.

Now, there are a couple of reactions to a project like this when it comes across your desk. First and foremost is bemusement that someone would spend time and effort on a project like this — not that we don’t appreciate it; the icons alone are worth the price of admission. Next is sheer amazement that NASA provides access to a parameter like this in its public API, with a close second being the temptation to look at what other cool endpoints they expose.

But for my part, the first thing I thought of when I saw that project was, “How do they even measure liquid levels in space?” In a place where up and down don’t really have any practical meaning, the engineering challenges of liquid measurement must be pretty interesting. That led me down the rabbit hole of low-gravity process engineering, a field that takes everything you know about how fluids behave and flushes it into the space toilet.

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Radio Apocalypse: America’s Doomsday Rocket Radios

August 25, 2025 by 17 Comments

Even in the early days of the Cold War, it quickly became apparent that simply having hundreds or even thousands of nuclear weapons would never be a sufficient deterrent to atomic attack. For nuclear weapons to be anything other than expensive ornaments, they have to be part of an engineered system that guarantees that they’ll work when they’re called upon to do so, and only then. And more importantly, your adversaries need to know that you’ve made every effort to make sure they go boom, and that they can’t interfere with that process.

In practical terms, nuclear deterrence is all about redundancy. There can be no single point of failure anywhere along the nuclear chain of command, and every system has to have a backup with multiple backups. That’s true inside every component of the system, from the warheads that form the sharp point of the spear to the systems that control and command those weapons, and especially in the systems that relay the orders that will send the missiles and bombers on their way.

When the fateful decision to push the button is made, Cold War planners had to ensure that the message got through. Even though they had a continent-wide system of radios and telephone lines that stitched together every missile launch facility and bomber base at their disposal, planners knew how fragile all that infrastructure could be, especially during a nuclear exchange. When the message absolutely, positively has to get through, you need a way to get above all that destruction, and so they came up with the Emergency Rocket Communication System, or ERCS.

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Hackaday Links: August 24, 2025

August 24, 2025 by 9 Comments

“Emergency Law Enforcement Officer Hologram program activated. Please state the nature of your criminal or civil emergency.” Taking a cue from Star Trek: Voyager, the Seoul Metropolitan Police Agency is testing a holographic police officer, with surprisingly — dare we say, suspiciously? — positive results. The virtual officer makes an appearance every two minutes in the evening hours in a public park, presumably one with a history of criminal activity. The projection is accompanied by a stern warning that the area is being monitored with cameras, and that should anything untoward transpire, meat-based officers, presumably wearing something other than the dapper but impractical full-dress uniform the hologram sports, will be dispatched to deal with the issue.

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Hackaday Links: August 17, 2025

August 17, 2025 by 15 Comments

We’ve studiously avoided any mention of our latest interstellar visitor, 3I/Atlas, on these pages, mainly because of all the hoopla in the popular press about how Avi Loeb thinks it’s aliens, because of course he does. And we’re not saying it’s aliens either, mainly because we’d never be lucky enough to be alive during an actual alien invasion — life just hasn’t historically been that kind to us. So chances are overwhelming that 3I/Atlas is just a comet, but man, it’s doing its level best to look like it’s not, which means it’s time to brave the slings and arrows and wade into this subject.

The number of oddities surrounding 3I/Atlas just keeps growing, from its weird Sun-directed particle stream to its extreme speed, not to mention a trajectory through the solar system that puts it just a fraction of an astronomical unit from two of the three planets within the “Goldilocks Zone” of our star — ignore the fact that at an estimated seven billion years old, 3I/Atlas likely would have started its interstellar journey well before our solar system had even started forming. Still, it’s the trajectory that intrigues us, especially the fact that it’s coming in at a very shallow along to the ecliptic, and seems like it will cross that imaginary plane almost exactly when it makes its closest approach to the Sun on October 29, which just coincidentally happens to be at the very moment Earth is exactly on the opposite side of our star. We’ll be as far as possible from the action on that date, with the comet conveniently lost in the glare of the Sun. Yes, there’s talk of re-tasking some of our spacecraft around Mars or in the Jovian system to take a peek when 3I/Atlas passes through their neighborhoods, but those are complicated affairs that show no sign of bearing fruit in the short time left before the comet heads back out into the Deep Dark. Too bad; we’d really love an up-close and personal look at this thing.

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