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Radio Apocalypse: HFGCS, The Backup Plan For Doomsday

August 5, 2024 by 16 Comments

To the extent that you have an opinion on something like high-frequency (HF) radio, you probably associate it with amateur radio operators, hunched over their gear late at night as they try to make contact with a random stranger across the globe to talk about the fact that they’re both doing the same thing at the same time. In a world where you can reach out to almost anyone else in an instant using flashy apps on the Internet, HF radio’s reputation as somewhat old and fuddy is well-earned.

Like the general population, modern militaries have largely switched to digital networks and satellite links, using them to coordinate and command their strategic forces on a global level. But while military nets are designed to be resilient to attack, there’s only so much damage they can absorb before becoming degraded to the point of uselessness. A backup plan makes good military sense, and the properties of radio waves between 3 MHz and 30 MHz, especially the ability to bounce off the ionosphere, make HF radio a perfect fit.

The United States Strategic Forces Command, essentially the people who “push the button” that starts a Very Bad Day™, built their backup plan around the unique properties of HF radio. Its current incarnation is called the High-Frequency Global Communications System, or HFGCS. As the hams like to say, “When all else fails, there’s radio,” and HFGCS takes advantage of that to make sure the end of the world can be conducted in an orderly fashion.

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End Of An Era: Sony Cuts Production Of Writable Optical Media

July 25, 2024 by 64 Comments

The 1990s saw a revolution occur, launched by the CD burner. As prices of writeable media and drives dropped, consumers rushed to duplicate games, create their own mix CDs, and backup their data on optical disc. It was a halcyon time.

Fast forward to today, and we’re very much on downward curve when it comes to optical media use. Amidst ever-declining consumer interest, Sony has announced it will cut production of writeable optical media. Let’s examine what’s going on, and explore the near future for writable optical discs.

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Solar Dynamics Observatory: Our Solar Early Warning System

July 9, 2024 by 3 Comments

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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Access To Fresh And Potable Water: An Ancient And Very Current Challenge

July 2, 2024 by 28 Comments

Throughout history, clean and potable water has been one of the most prized possessions, without which no human civilization could have ever sustained itself. Not only is water crucial for drinking and food preparation, but also for agriculture, cleaning and the production of countless materials, chemicals and much more. And this isn’t a modern problem: good water supplies and the most successful ancient cultures go hand in hand.

For instance, the retention and management of fresh water in reservoirs played a major role in the Khmer Empire, with many of its reservoirs (baray) surviving to today. Similarly, the Anuradhapure Kingdom in Ceylon (now Sri Lanka) featured massive reservoirs like Kala Wewa that was constructed in 460 CE with a capacity of 123 million m3. In the New World, the Maya civilization similarly created reservoirs with intricate canals to capture rainwater before the dry season started, as due to the karst landscape wells were not possible.

Keeping this water fresh and free from contaminants and pollution was a major problem for especially the Maya, with a recent perspective by Lisa J. Lucera in PNAS Anthropology suggesting that they used an approach similar to modern day constructed wetlands to keep disease and illness at bay, while earlier discoveries also suggest the use of filtration including the use of zeolite.

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A Brief History Of Perpetual Motion

July 1, 2024 by 65 Comments

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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The SS United States: The Most Important Ocean Liner We May Soon Lose Forever

June 27, 2024 by 14 Comments

Although it’s often said that the era of ocean liners came to an end by the 1950s with the rise of commercial aviation, reality isn’t quite that clear-cut. Coming out of the troubled 1940s arose a new kind of ocean liner, one using cutting-edge materials and propulsion, with hybrid civil and military use as the default, leading to a range of fascinating design decisions. This was the context in which the SS United States was born, with the beating heart of the US’ fastest battle ships, with light-weight aluminium structures and survivability built into every single aspect of its design.

Outpacing the super-fast Iowa-class battleships with whom it shares a lot of DNA due to its lack of heavy armor and triple 16″ turrets, it easily became the fastest ocean liner, setting speed records that took decades to be beaten by other ocean-going vessels, though no ocean liner ever truly did beat it on speed or comfort. Tricked out in the most tasteful non-flammable 1950s art and decorations imaginable, it would still be the fastest and most comfortable way to cross the Atlantic today. Unfortunately ocean liners are no longer considered a way to travel in this era of commercial aviation, leading to the SS United States and kin finding themselves either scrapped, or stuck in limbo.

In the case of the SS United States, so far it has managed to escape the cutting torch, but while in limbo many of its fittings were sold off at auction, and the conservation group which is in possession of the ship is desperately looking for a way to fund the restoration. Most recently, the owner of the pier where the ship is moored in Philadelphia got the ship’s eviction approved by a judge, leading to very tough choices to be made by September.

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The Solar System Is Weirder Than You Think

June 17, 2024 by 50 Comments

When I was a kid, the solar system was simple. There were nine planets and they all orbited in more-or-less circles around the sun. This same sun-and-a-handful-of-planets scheme repeated itself again and again throughout our galaxy, and these galaxies make up the universe. It’s a great story that’s easy to wrap your mind around, and of course it’s a great first approximation, except maybe that “nine planets” thing, which was just a fluke that we’ll examine shortly.

What’s happened since, however, is that telescopes have gotten significantly better, and many more bodies of all sorts have been discovered in the solar system which is awesome. But as a casual astronomy observer, I’ve given up hope of holding on to a simple mental model. The solar system is just too weird.

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