Polaroid In An Instant

Edwin Land, were he alive, would hate this post. He wanted to be known for this scientific work and not for his personal life. In fact, upon his death, he ordered the destruction of all his personal papers. However, Land was, by our definition, a hacker, and while you probably correctly associate him with the Polaroid camera, that turns out to be only part of the story.

Land in 1977

It was obvious that Land was intelligent and inquisitive from an early age. At six, he blew all the fuses in the house. He was known for taking apart clocks and appliances. When his father forbade him from tearing apart a phonograph, he reportedly replied that nothing would deter him from conducting an experiment. We imagine many Hackaday readers have similar childhood stories.

Optics

He was interested in optics, and at around age 13, he became interested in using polarized light to reduce headlight glare. The problem was that one of the best polarizing crystals known — herapathite — was difficult to create in a large size. Herapathite is a crystalline form of iodoquinine sulfate studied in the 1800s by William Herapath, who was unable to grow large sizes of the crystal. Interestingly, one of Herapath’s students noticed the crystals formed when adding iodine to urine from dogs that were given quinine.

Land spent a year at Harvard studying physics, but he left and moved to New York. He continued trying to develop a way to make large, practical, light-polarizing crystals. At night, he would sneak into labs at Columbia University to conduct experiments.

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Small Mammals Appear To Have A Secret Infrared Sense

If you’ve ever watched Predator, you’ve noted the tactical advantage granted to the alien warrior by its heat vision. Indeed, even with otherwise solid camoflauge, Dutch and his squad ended up very much the hunted.

And yet, back in reality, it seems the prey might be the one with the ability to sense in the infrared spectrum. Research has now revealed this unique ability may all be down to the hairs on the back of some of the smallest mammals.

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Making Art With Maxwell’s Equations

When you think of art, you might think of portraiture, landscapes, or other kinds of paintings. But mathematics can feel artistic at times, too. We’ve all seen gorgeous Mandelbrot fractals, and less gorgeous Julia fractals, but that’s not all that’s out there. As [Prof. Halim Boutayeb] demonstrates, Maxwell’s equations can show us some real beauty, too.

Find us a cooler graph than this one!

The work involves running simulations of multiple electromagnetic sources moving, bouncing around, interacting, and so on. The art comes in the plotting of the fields, in warm colors or just outright rainbows. The professor does a great job of pairing some of these videos with pumping electronic music, which only adds to the fun.

Of course, the colors are pretty, but there’s a lot of valuable physics going on behind all this. Thankfully, there are all kinds of additional resources linked for those eager to learn about the Finite Difference Time Domain method and how it can be used for valid simulation tasks.

Throw this kind of stuff on a projector at your next rave and you will not be disappointed. Video after the break.

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Hackaday Links: July 14, 2024

We’ve been going on at length in this space about the death spiral that AM radio seems to be in, particularly in the automotive setting. Car makers have begun the process of phasing AM out of their infotainment systems, ostensibly due to its essential incompatibility with the electronics in newer vehicles, especially EVs. That argument always seemed a little specious to us, since the US has an entire bureaucracy dedicated to making sure everyone works and plays well with each other on the electromagnetic spectrum. The effort to drop AM resulted in pushback from US lawmakers, who threatened legislation to ensure every vehicle has the ability to receive AM broadcasts, on the grounds of its utility in a crisis and that we’ve spent billions ensuring that 80% of the population is within range of an AM station.

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Solar Dynamics Observatory: Our Solar Early Warning System

Ever since the beginning of the Space Age, the inner planets and the Earth-Moon system have received the lion’s share of attention. That makes sense; it’s a whole lot easier to get to the Moon, or even to Mars, than it is to get to Saturn or Neptune. And so our probes have mostly plied the relatively cozy confines inside the asteroid belt, visiting every world within them and sometimes landing on the surface and making a few holes or even leaving some footprints.

But there’s still one place within this warm and familiar neighborhood that remains mysterious and relatively unvisited: the Sun. That seems strange, since our star is the source of all energy for our world and the system in general, and its constant emissions across the electromagnetic spectrum and its occasional physical outbursts are literally a matter of life and death for us. When the Sun sneezes, we can get sick, and it has the potential to be far worse than just a cold.

While we’ve had a succession of satellites over the last decades that have specialized in watching the Sun, it’s not the easiest celestial body to observe. Most spacecraft go to great lengths to avoid the Sun’s abuse, and building anything to withstand the lashing our star can dish out is a tough task. But there’s one satellite that takes everything that the Sun dishes out and turns it into a near-constant stream of high-quality data, and it’s been doing it for almost 15 years now. The Solar Dynamics Observatory, or SDO, has also provided stunning images of the Sun, like this CGI-like sequence of a failed solar eruption. Images like that have captured imaginations during this surprisingly active solar cycle, and emphasized the importance of SDO in our solar early warning system.

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Making EV Motors, And Breaking Up With Rare Earth Elements

Rare earth elements are used to produce magnets with very high strength that also strongly resist demagnetization, their performance is key to modern motors such as those in electric vehicles (EVs). The stronger the magnets, the lighter and more efficient a motor can be. So what exactly does it take to break up with rare earths?

Rare earth elements (REEs) are actually abundant in the Earth’s crust, technically speaking. The problem is they are found in very low concentrations, and inconveniently mixed with other elements when found. Huge amounts of ore are required to extract useful quantities, which requires substantial industrial processing. The processes involved are ecologically harmful and result in large amounts of toxic waste.

Moving away from rare earth magnets in EV motors would bring a lot of benefits, but poses challenges. There are two basic approaches: optimize a motor for non-rare-earth magnets (such as iron nitrides), or do away with permanent magnets entirely in favor of electromagnets (pictured above). There are significant engineering challenges to both approaches, and it’s difficult to say which will be best in the end. But research and prototypes are making it increasingly clear that effective REE-free motors are perfectly feasible. Breaking up with REEs and their toxic heritage would be much easier when their main benefit — technological performance — gets taken off the table as a unique advantage.

A Brief History Of Perpetual Motion

Conservation of energy isn’t just a good idea: It is the law. In particular, it is the first law of thermodynamics. But, apparently, a lot of people don’t really get that because history is replete with inventions that purport to run forever or produce more energy than they consume. Sometimes these are hoaxes, and sometimes they are frauds. We expect sometimes they are also simple misunderstandings.

We thought about this when we ran across the viral photo of an EV with a generator connected to the back wheel. Of course, EVs and hybrids do try to reclaim power through regenerative braking, but that’s recovering a fraction of the energy already spent. You can never pull more power out than you put in, and, in fact, you’ll pull out substantially less.

Not a New Problem

If you think this is a scourge of social media and modern vehicles, you’d be wrong. Leonardo da Vinci, back in 1494, said:

Oh ye seekers after perpetual motion, how many vain chimeras have you pursued? Go and take your place with the alchemists.

There was a rumor in the 8th century that someone built a “magic wheel,” but this appears to be little more than a myth. An Indian mathematician also claimed to have a wheel that would run forever, but there’s little proof of that, either. It was probably an overbalanced wheel where the wheel spins due to weight and gravity with enough force to keep the wheel spinning.

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