A schematic representation of the different ionospheric sub-layers and how they evolve daily from day to night periods. (Credit: Carlos Molina)

Will Large Satellite Constellations Affect Earth’s Magnetic Field?

February 7, 2024 by Maya Posch 48 Comments

Imagine taking a significant amount of metals and other materials out of the Earth’s crust and scattering it into the atmosphere from space. This is effectively what we have been doing ever since the beginning of the Space Age, with an increasing number of rocket stages, satellites and related objects ending their existence as they burn up in the Earth’s atmosphere. Yet rather than vanish into nothing, the debris of this destruction remains partially in the atmosphere, where it forms pockets of material. As this material is often conductive, it will likely affect the Earth’s magnetic field, as argued by [Sierra Solter-Hunt] in a pre-publication article.

A summary by [Dr. Tony Phillips] references a 2023 NASA research article by [Daniel M. Murphy] et al. which describes the discovery that about 10% of the aerosol particles in the stratosphere are aluminium and other metals whose origin can be traced back to the ‘burn-up’ of the aforementioned space objects. This is a factor which can increase the Debye length of the ionosphere. What the exact effects of this may be is still largely unknown, but fact remains that we are launching massively more objects into space than even a decade ago, with the number of LEO objects consequently increasing.

Although the speculation by [Sierra] can be called ‘alarmist’, the research question of what’ll happen if over the coming years we’ll have daily Starlink and other satellites disintegrating in the atmosphere is a valid one. As this looks like it will coat the stratosphere and ionosphere in particular with metal aerosols at levels never seen before, it might be worth it to do the research up-front, rather than wait until we see something odd happening.

Metal Crystal Stops Electrons

February 7, 2024 by Al Williams 14 Comments

Researchers at Rice University have found an alloy of copper, vanadium, and sulfur that forms crystals that, due to quantum effects, can trap electrons. This can produce flat bands, which have been observed in 2D crystals previously. The team’s results are the first case of a 3D crystal with that property.

The flat band term refers to the electron energy bands. Normally, the electrons change energy levels based on momentum. But in a flat band, this doesn’t occur. This implies that the electrons are nearly stationary, which leads to unique optical, electronic, and magnetic properties. In addition, flat-band materials often exhibit unusual behavior, such as exotic quantum states, ferromagnetism, or even superconductivity.

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Your 1983 Video Phone Is Finally Ready

February 7, 2024 by Al Williams 8 Comments

If you read Byte magazine in 1983, you might have expected that, by now, you’d be able to buy the red phone with the video screen built-in. You know, like the one that appears on the cover of the magazine. Of course, you can’t. But that didn’t stop former Hackaday luminary [Cameron] from duplicating the mythical device, if not precisely, then in spirit. Check it out in the video, below.

While the original Byte article was about VideoTex, [Cameron] built a device with even more capability you couldn’t have dreamed of in 1983. What’s more, the build was simple. He started with an old analog phone and a tiny Android phone. A 3D-printed faceplate lets the fake phone serve as a sort of dock for the cellular device.

That’s not all, though. Using the guts of a Bluetooth headset enables the fake phone’s handset. Now you can access the web — sort of a super Videotex system. You can even make video calls.

There isn’t a lot of detail about the build, but you probably don’t need it. This is more of an art project, and your analog phone, cell phone, and Bluetooth gizmo will probably be different anyway.

Everyone always wanted a video phone, and while we sort of have them now, it doesn’t quite seem the same as we imagined them. We wish [Cameron] would put an app on the phone to simulate a rotary dial and maybe even act as an answering machine.

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Tetris Goes Full Circle

February 7, 2024 by Bryan Cockfield 10 Comments

As a game concept, Tetris gave humanity nearly four solid decades of engagement, but with the possibility for only seven possible puzzle pieces it might seem a little bit limiting. Especially now that someone has finally beaten the game, it could be argued that as a society it might be time to look for something new. Sinusoidal Tetris flips these limits on their head with a theoretically infinite set of puzzle pieces for an unmistakable challenge.

Like Tetris, players control a game piece as it slowly falls down the screen. Instead of blocks, however, the game piece is a sinusoid that stretches the entire width of the screen. Players control the phase angle, amplitude, and angular frequency in order to get it to cancel out the randomly-generated wave in the middle of the screen. When the two waves overlap, a quick bit of math is done to add the two waves together. If your Fourier transformation skills aren’t up to the task, the sinusoid will eventually escape the playing field resulting in a game over. The goal then is to continually overlap sinusoids to play indefinitely, much like the original game.

While we’re giving Tetris a bit of a hard time, we appreciate the simplicity of a game that’s managed to have a cultural impact long after the gaming systems it was originally programmed for have become obsolete, and this new version is similar in that regard as well. The game can be quite addictive with a lot to take in at any given moment. If you’re more interested in the programming for these types of games than the gameplay, though, take a look at this deep-dive into Tetris for the NES.

Friendly Flexible Circuits: The Cables

February 7, 2024 by Arya Voronova 18 Comments

Flexible cables and flex PCBs are wonderful. You could choose to carefully make a cable bundle out of ten wires and try to squish them to have a thin footprint – or you could put an FFC connector onto your board and save yourself a world of trouble. If you want to have a lot of components within a cramped non-flat area, you could carefully design a multitude of stuff FR4 boards and connect them together – or you could make an FPC.

Flexible cables in particular can be pretty wonderful for all sorts of moving parts. They transfer power and data to the scanner head in your flat-bed scanner, for instance. But they’re in fixed parts too. If you have a laptop or a widescreen TV, chances are, there’s an flexible cable connecting the motherboard with one or multiple daughterboards – or even a custom-made flexible PCB. Remember all the cool keypad and phones we used to have, the ones that would have the keyboard fold out or slide out, or even folding Nokia phones that had two screens and did cool things with those? All thanks to flexible circuits! Let’s learn a little more about what we’re working with here.

FFC and FPC, how are these two different? FFC (Flexible Flat Cable) is a pre-made cable. You’ve typically seen them as white plastic cables with blue pieces on both ends, they’re found in a large number of devices that you could disassemble, and many things use them, like the Raspberry Pi Camera. They are pretty simple to produce – all in all, they’re just flat straight conductors packaged nicely into a very thin cable, and that’s why you can buy them pre-made in tons of different pin pitches and sizes. If you need one board to interface with another board, putting an FFC connector on your board is a pretty good idea.

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Vesuvius Challenge 2023 Grand Prize Awarded And 2024’s New Challenge

February 7, 2024 by Maya Posch 7 Comments

In the year 79 CE, a massive cloud of volcanic ash rained down on the Roman city of Herculaneum after an eruption of Mount Vesuvius. Along with the city of Pompeii, Herculaneum was subsequently engulfed and buried by a pyroclastic flow that burned everything in its path, including the scrolls in the library of what today is known as the Villa of the Papyri. After the charred but still recognizable scrolls were found in the 18th century, many fruitless attempts were made to recover the text hidden within these charred ruins, but not until 2023 did we get our first full glimpse at their contents, along with the awarding of the Vesuvius Challenge 2023.

We previously covered the run-up to this award, but with only a small fraction of the scrolls now read, there’s still a long way to go. This leads to the 2024 prize challenge, which sees teams strive to read 90% of scrolls 1-4 each, for a $100,000 award. The expectation is that with this ability, it should be possible to read all 800 scrolls known today, but as detailed in the Master Plan there is still more to come. Being able to scan and process scrolls faster and more efficiently is one of the biggest challenges, as is that of recovering any more scrolls that may be stuck in the mud at the Villa of the Papyri. As easy as it may sound to pull stuff out of the mud, archaeological excavations are expensive and time-consuming.

With time running out on how long both the recovered and still lost scrolls will last, it’s pertinent that we do not lose this opportunity to double our knowledge of historical texts from this era.