2026-03-02 23:00:07
For many decades humankind has entertained the notion that we can maybe tweak the Earth’s atmosphere or biosphere in such a way that we can for example undo the harms of climate change, or otherwise affect the climate for our own benefit. This often involves spreading certain substances in parts of the atmosphere in order to reflect or retain thermal solar radiation or induce rain.
Yet despite how limited in scope these attempts at such intentional experiments have been so far – with most proposals dying somewhere before being implemented – we have already embarked on a potentially planet-wide atmospheric reconfiguration that could affect life on Earth for centuries to come. This accidental experiment comes in the form of rocket stages, discarded satellites, and other human-made space litter that burn up in the atmosphere at ever increasing rates.
Rather than burning up cleanly into harmless components, this actually introduces metals and other compounds into the upper parts of the atmosphere. What the long-term effects of this will be is still uncertain, but with the most dire scenarios involving significant climate change and ozone layer degradation, we ought to figure this one out sooner rather than later.
Although Earth’s atmosphere looks pretty peaceful if you’re gazing at it from a space station in LEO or from a commercial airliner at cruising altitude, it’s actually constantly being assaulted. Everything from radiation to meteoroids, as well as the occasional asteroid are constantly making an attempt at inflicting real harm. This ranges all the way up to another mass-extinction event, but a meteoroid will settle for at the very least flattening another forest or inconveniencing a home owner.
Fortunately the atmosphere provides another feature beyond allowing us to not suffocate: by providing strong friction, the resulting high temperatures and intense plasma formation tend to burn up any object that tries to enter it at high velocity.
A less extreme form of this comes in the form of aerobraking, which is what spacecraft use to reduce their velocity relative to the planet; by creating enough friction in the atmosphere to shed kinetic energy, yet not heating up the spacecraft’s exterior to the point where things begin to melt, is incredibly helpful if one wishes to avoid having to resort to Plan B, being the violence of lithobraking.
This incinerator feature of the atmosphere is also very useful when it comes to the question of where the trash goes, whether it’s literal trash from the International Space Station, or things like discarded rocket stages and fairings, all the way to satellites that have reached their end of life stage. Yet much like the medieval solutions to waste disposal, the theme here is very much an ‘out of sight, out of mind’ approach, which is understandable as long as the volume of waste is still relatively small.
When a human-made object disintegrates in the atmosphere, it’s reduced to its base compounds, after interaction with the super-heated plasma that forms around said object. With the commonly used aluminium, for example, this means the production of aluminium oxide.
By far the largest amount of mass that will be burning up in the atmosphere over the coming years is formed by LEO internet constellations such as Starlink, which have a cumulative mass of over 10,000 tons. In addition, the second stage of the Falcon 9 rockets that are currently used to launch Starlink v1 and v1.5 satellites into LEO also burns up in the atmosphere. Recently, such a Falcon 9 stage suffered a mishap that caused it to disintegrate over Europe, rather than the typical trajectory over remote parts of Earth’s oceans.
This provided the perfect natural experiment. Batteries onboard satellites contain lithium, and because it’s relatively scarce in the atmosphere, it makes a great marker for the effects of satellites burning up on re-entry.
In the article by Robin Wing et al., as published in Communications Earth & Environment, the upper atmosphere measurements by a resonance lidar in Germany allowed for a ten-fold increase in atomic lithium to be measured after the stage had disintegrated near Ireland at an altitude of 100 km. Air currents subsequently dispersed the atomic debris over the rest of Europe.
Most notable perhaps was that the plume of atomic lithium was being detected at the same altitude of 100 km, after advecting for 1,600 km, placing ablation and dispersal in the mesosphere and lower thermosphere (MLT). Normally this plume would be dispersed far away from instruments, making it a fortuitous event from a scientific perspective that it could be measured like this.
Lithium is just one tracer for the debris plume, but there are many other metals. Here also lies the issue with comparing purely the mass of asteroids and rocket stages burning up in the atmosphere versus meteoroids and asteroids doing the same. The latter aren’t usually composed of intricate collections of metal alloys, rare earths and composite materials, but generally more boring things that we’d generously call ‘rocks’ or ‘gravel’, with the occasional iron variant mixed in.
As noted by Robin Wing et al., this feature makes artificial sources relatively easy to distinguish from natural ones. Since within the next decades re-entering satellites are projected to match or exceed 40% of natural meteoroid influx, the question remains of what these substances hanging around in Earth’s atmosphere will do to it and consequently life in Earth’s biosphere.
Back in 1987 the Montreal Protocol was signed. This banned the use of chlorofluorocarbons (CFCs) after it was found that the large-scale release of CFCs into the atmosphere from refrigeration systems and other sources had resulted in a significant depletion of the ozone layer. This layer is found primarily in Earth’s stratosphere and is essential for blocking harmful ultraviolet radiation which would otherwise irradiate the surface, in particular UV-C.
Although it’s currently projected that the ozone will have completely regenerated by 2045, a worrying 2024 research letter by José P. Ferreira et al. from the American Geophysical Union (AGU) with accompanying press release suggests that the massive rise in satellites burning up in the atmosphere over the coming decades could add so much aluminium oxides to the atmosphere that it could revert this ozone layer regeneration process.
Using an atomic-scale molecular dynamics simulation they found that a typical 250 kg satellite upon its fiery demise in Earth’s atmosphere releases about 30 kg of aluminium oxide nanoparticles. These may remain in the atmosphere for decades, meanwhile acting as a catalyst for chlorine activation and thus ozone depletion.
With currently projected mass of mega-constellation satellites burning up in the atmosphere, we’d be looking over 360 tons of aluminium oxides per year being added. As a catalyst, these aluminium oxides would not be used up, but would keep depleting the ozone layer as fast as the input products (ClO or Cl) are added.
This is just one potential impact that we might see as we keep adding all of these foreign substances to the atmosphere. Fortunately there’s nothing that says that we cannot have all our satellites and still dodge these issues.
The central issue here is that we have always treated the atmosphere similarly to the way that early medieval cities treated the local waterways. In their case it only took a few cholera- and other assorted epidemics to realize that maybe it was best to not use the waterways both for waste and drinking water. Similarly, we are now at a point where we’re beginning to realize that tossing our waste into the atmosphere may not be such a good plan, albeit it largely for financial reasons.
For many decades, it’s been accepted that rockets and satellites are effectively disposable, single-use items. Even the infamous STS (‘Shuttle’) program didn’t really push it much past ‘intense refurbishing’. Only recently has it become fashionable to reuse rockets and capsules, with the SpaceX Falcon 9 rocket’s first stage currently being the world-leader when it comes to partial reuse. Unfortunately its second stage still is burned up, as we saw with the analysis by Robin Wing et al.
What can be done? Back in 2020 we covered Northrop Grumman’s Mission Extension Vehicle (MEV), which provides a way to latch onto an existing satellite and provide propulsion as well as other functionality when the target’s own resources have become exhausted. In 2021 MEV-2 docked with Intelsat 10-02 to push it back to a geosynchronous orbit, extending its life by five years.
This is an example of on-orbit satellite servicing, which can take many forms. At its most basic it will just drag a satellite to a specific orbit, but it can also entail actual servicing, refueling and repairs. This was actually one of the concepts behind the Shuttle, with the Hubble Telescope being serviced and upgraded during a number of missions.
Unfortunately with the STS program’s in-orbit repair feature remaining mostly a pleasant dream due to the high cost of such a mission, we may one day see satellites being refueled and repaired by robotic systems. Although fully reusable rockets seem to be just around the horizon with SpaceX Starship and kin leading the way, we can only hope that we can soon figure out a way to make it cheaper to just repair a satellite than to toss it and launch a new one.
2026-03-02 20:00:01
[Yeckel] recently put the finishing touches on an ambitious implementation of a simple D-STAR (Digital Smart Technologies for Amateur Radio) transceiver using some very accessible and affordable hardware. The project is D-StarBeacon, and [Yeckel] shows it working on a LilyGO TTGO T-Beam, an ESP32-based development board that includes a SX1278 radio module and GPS receiver. It even serves a web interface for easy configuration.
What is D-STAR? It’s a protocol used by radio operators for voice that also allows transmitting low-speed data, such as short text messages or GPS coordinates. While voice is out of scope for [Yeckel]’s project (more on that in a moment) it can do all the rest, including send images. That makes beacon-type functions possible on inexpensive hardware, instead of requiring a full-blown radio.
As mentioned, voice is a big part of D-STAR. While [Yeckel] was able to access the voice data, attempts to decode it were unsuccessful. A valiant effort, but we suppose voice decoding isn’t terribly relevant to beacon-type operations like transmitting APRS (Automatic Packet Reporting System).
So far as [Yeckel] is aware, D-StarBeacon is currently the only open-source implementation of a D-STAR radio available on the internet, which is pretty interesting. We’ve seen projects that touch indirectly on D-STAR, but nothing like this.
Watch it go through its paces in the video embedded below. Since the T-Beam is just a microcontroller development board, the user interface comes from an Android app on a mobile phone, which is why you see a phone in the video.
2026-03-02 17:00:23
There aren’t many speed records that remain unbroken for the greater part of a century, but one of them is that of the fastest steam locomotive. As with so many such things, there’s a bit of controversy and more than one contender, but the one in the record books is the A4 Pacific, Mallard. In 1938, this locomotive thundered down an incline on the London & North Eastern Railway’s mainline in the north of England at 126 MPH. But can that number be taken as reliable? The Institute of Mechanical Engineers has a video in which they investigate.
It’s a fascinating look at the science of railway speed measurement as it existed in 1938, the record itself, and the paper dynamometer roll which recorded it. We’ve placed the video below the break, and in it, we see an in-depth analysis of the noise and inconsistencies in the recording, and see them come to the conclusion that a safer figure to quote would be 124 MPH.
Our assessment is that, of course, the LNER wanted to squeeze every morsel of publicity from it in a game of one-upmanship with their arch-rivals in the London Midland and Scottish railway, so it’s likely that their use of a momentary figure makes sense in that light. Even the best-laid 1930s jointed track would have been bumpy compared to modern continuous rail, and we are guessing that the ancient clerestory dynamometer car would hardly be as smooth-riding as a modern express coach. The achievement of measuring at all with mechanical instruments in such an environment at those speeds would have been tricky, to say the least. It leaves us wondering whether 1930s electronics could have produced some kind of trackside measurement device, but perhaps the LNER trusted their mechanical instruments more. Perhaps the Pennsylvania Railroad should have followed its example.
2026-03-02 14:00:39
Everyone loves Wago connectors for how versatile and effective they are for quickly and securely connecting conductors, but it can be tempting to buy a bag of the significantly cheaper knock-offs. The reason why this can be a terrible idea is explained by [Big Clive] who tore down a few bags of them to ogle at their internals.
The main problem with some of these knock-offs is the way that they use the plastic molding as part of the structure that holds the conductors in place. Over time this plastic will develop larger tolerances, with heat developed from passing large currents speeding up the process. As the examined type of connector relies on metal clamps that securely push the conductor onto the busbar, having the plastic weaken, and the clamp correspondingly loosen up, is clearly not a desirable scenario.
As [Clive] says in the video, you’re probably okay using these cheapo knock-offs for a quick test on the bench, but you should never put them in a permanent installation. Not just due to potential fiery scenarios, but also for insurance claims should the worst come to pass, and the insurance company finds dodgy connectors everywhere in the electrical wiring. This isn’t the first we’ve heard of knock-off Wago problems.
2026-03-02 11:00:39
[Nagy Krisztián] had an Intel 286 CPU, only… There was no motherboard to install it in. Perhaps not wanting the processor to be lonely, [Nagy] built a simulated system to bring the chip back to life.
The concept is simple enough. [Nagy] merely intended to wire the 286 up to a Raspberry Pi Pico that could emulate other parts of a computer that it would normally expect to talk to. This isn’t so hard with an ancient CPU like the 286, which has just 68 pins compared to the 1000+ pins on modern CPUs. All it took was a PLCC-68 socket, an adapter PCB, a breadboard, and some MCP23s17 logic expanders to give the diminutive microcontroller enough I/O. With a bit of work, [Nagy] was able to get the Pi Pico running the 286, allowing it to execute a simple program that retrieves numbers from “memory” and writes them back in turn.
Notably, this setup won’t run the 286 at its full clock speed of 12 MHz, and it’s a long way off from doing anything complex like talking to peripherals or booting an OS. Still, it’s neat to see the old metal live again, even if it’s just rattling through a few simple machine instructions that don’t mean a whole lot. [Nagy] equates this project to The Matrix; you might also think of it as a brain in a jar. The 286 is not in a real computer; it’s just hooked up to a microcontroller stimulating its various pins in a way that is indistinguishable from its own perspective.
We’ve seen similar retro projects before, such as this FPGA rig that helped a NEC V20 get back on its feet. If you’re doing your own tinkering on the platforms of yesteryear, we probably want to know about it on the tips line.
2026-03-02 08:00:55
We’ll start this week off with a bit of controversy from Linux Land. Anyone who’s ever used the sudo command knows that you don’t see any kind of visual feedback while entering your password. This was intended as a security feature, as it was believed that an on-screen indicator of how many characters had been entered would allow somebody snooping over your shoulder to figure out the length of your password. But in Ubuntu 26.04, that’s no longer the case. The traditional sudo binary has been replaced with a one written in Rust, which Canonical has recently patched to follow the modern convention of showing asterisks on the password prompt.
As you might expect, this prompted an immediate reaction from Linux greybeards. A bug report was filed just a few days ago demanding that the change be reverted, arguing that breaking a decades-old expectation with no warning could be confusing for users. The official response from a Canonical dev was that they see it the other way around, and that the change was made to improve the user experience. It was also pointed out that those who want to revert to the old style of prompt can do so with a config change. The issue was immediately marked as “Won’t Fix”, but the discussion is ongoing.
Speaking of unexpected changes, multiple reports are coming in that the February security update for Samsung Galaxy devices, which is currently rolling out, removes several functions from the Android recovery menu. After the update is applied to phones such as the S25 and Fold 7, long-standing features, such as the ability to wipe the device’s cache partition or install updates via Android Debug Bridge (ADB), disappear.
Just like with the change to sudo, this is the sort of thing that will aggravate veteran users the most. There’s been no official explanation for these changes, and it’s not immediately obvious why Samsung would fiddle with the recovery menu that’s remain largely unchanged since Android’s introduction. As 9to5Google mentions, it could be an attempt to prevent users from installing leaked firmware builds — a practice that’s gotten the attention of the electronic giant’s legal department.
These days, software updates are just one of the things you need to keep track of. Add in emails, RSS feeds, and incoming chat messages, and keeping up with the notifications on your computer or smartphone can be a challenge. But that’s nothing compared to the 800,000 alerts fired off earlier this week by the Vera Rubin Observatory. The observatory uses a 3.2 gigapixel camera to take long exposure images of the night sky, which are then compared with earlier shots to detect visual changes. Astronomers create filters to narrow down what they’re after, and can be notified when the automated system detects a match. A preview image is available in just seconds, while the full-resolution imagery takes around 80 hours to process. It’s still early days, but once the VRO gets up to speed, it’s expected that as many as seven million alerts will be generated each night.
While on the subject of large-scale engineering projects, this week, Google announced that its new data center in Minnesota will be hooked up to the world’s largest battery. The 300 megawatt array built by Form Energy will use iron-air technology, which essentially uses a reversible rusting process to store energy produced by renewable sources such as wind and solar. When those sources aren’t available, the data center can run off of battery power for up to 100 hours.
While heavier and less efficient than lithium-ion, iron-air batteries have the advantage of being substantially cheaper to produce. So while it’s unlikely you’ll see the technology in smartphones anytime soon, it’s perfect for static installations like this.
Finally, some sad news from the world of retro computing/games: a very rare copy of Tsukihime Trial Edition was apparently destroyed while in transit from one collector to another. It might not look like much — the game was distributed by the indie developers on unbranded floppies at a Japanese convention in 1999 — but it represents one of only 50 copies known to exist. While the occasional damaged package is all but unavoidable, this one is particularly egregious as it appears that someone at US Customs intentionally ripped the disk to pieces. The purchaser has filed a complaint with Customs, and we’re interested in hearing what their version of the story sounds like.
See something interesting that you think would be a good fit for our weekly Links column? Drop us a line, we’d love to hear about it.
