Something’s Up In Switzerland: Explaining The B Meson News From The Large Hadron Collider

May 13, 2021 by Bob Baddeley 50 Comments

Particle physics is a field of extremes. Scales always have 10^{really big number} associated. Some results from the Large Hadron Collider Beauty (LHCb) experiment have recently been reported that are statistically significant, and they may have profound implications for the Standard Model, but it might also just be a numbers anomaly, and we won’t get to find out for a while. Let’s dive into the basics of quantum particles, in case your elementary school education is a little rusty.

It all starts when one particle loves another particle very much and they are attracted to each other, but then things move too fast, and all of a sudden they’re going in circles in opposite directions, and then they break up catastrophically…

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Historical Hackers: Emergency Antennas Launched By Kite

May 12, 2021 by Al Williams 24 Comments

Your airplane has crashed at sea. You are perched in a lifeboat and you need to call for help. Today you might reach for a satellite phone, but in World War II you would more likely turn a crank on a special survival radio.

These radios originated in Germany but were soon copied by the British and the United States. In addition to just being a bit of history, we can learn a few lessons from these radios. The designers clearly thought about the challenges stranded personnel would face and came up with novel solutions. For example, how do you loft a 300-foot wire up to use as an antenna? Would you believe a kite or even a balloon?

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The Russian Woodpecker: Official Bird Of The Cold War Nests In Giant Antenna

May 11, 2021 by Kristina Panos 45 Comments

On July 4th, 1976, as Americans celebrated the country’s bicentennial with beer and bottle rockets, a strong signal began disrupting shortwave, maritime, aeronautical, and telecommunications signals all over the world. The signal was a rapid 10 Hz tapping that sounded like a woodpecker or a helicopter thup-thupping on the roof. It had a wide bandwidth of 40 kHz and sometimes exceeded 10 MW.

This was during the Cold War, and plenty of people rushed to the conclusion that it was some sort of Soviet mind control scheme or weather control experiment. But amateur radio operators traced the mysterious signal to an over-the-horizon radar antenna near Chernobyl, Ukraine (then part of the USSR) and they named it the Russian Woodpecker. Here’s a clip of the sound.

The frequency-hopping Woodpecker signal was so strong that it made communication impossible on certain channels and could even be heard across telephone lines when conditions were right. Several countries filed official complaints with the USSR through the UN, but there was no stopping the Russian Woodpecker. Russia wouldn’t even own up to the signal’s existence, which has since been traced to an immense antenna structure that is nearly half a mile long and at 490 feet, stands slightly taller than the Great Pyramid at Giza.

This imposing steel structure stands within the irradiated forest near Pripyat, an idyllic town founded in 1970 to house the Chernobyl nuclear plant workers. Pictured above is the transmitter, also known as Duga-1, Chernobyl-2, or Duga-3 depending on who you ask. Located 30 miles northeast of Chernobyl, on old Soviet maps the area is simply labeled Boy Scout Camp. Today, it’s all within the Chernobyl Exclusion Zone.

It was such a secret that the government denied it’s existence, yet was being heard all over the world. What was this mammoth installation used for?

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The ARMv9 ISA, And What It Can Do For You

May 10, 2021 by Maya Posch 38 Comments

The number of distinct ARM Instruction Set Architectures (ISA) versions has slowly increased, with Arm adding a new version every few years. The oldest ISA version in common use today is ARMv6, with the ARMv6 ISA (ARM11) found in the original Raspberry Pi SBC and Raspberry Pi Zero (BCM2835). The ARMv6 ISA was introduced in 2002, followed by ARMv7 in 2005 (start of Cortex-A series) and ARMv8 in 2011. The latter was notable for adding 64-bit support.

With ARMv7 being the first of the Cortex cores, and ARMv8 adding 64-bit support in the form of AArch64, what notable features does ARMv9 bring to the table? As announced earlier this year, ARMv9’s focus appears to be on adding a whole host of features that should improve vector processing (vector extensions, or SVE) as well as digital signal processing (DSP) and security, with its Confidential Compute Architecture (CCA).

In addition to this, ARMv9 also includes all of the features that were added with ARMv8.1, v8.2, v8.3 and so on. In essence, this makes an ARMv9-based processor theoretically capable of going toe-to-toe with the best that Intel and AMD have to offer.

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How To Build A Turbo Car The Cheap, 90s Way

May 7, 2021 by Zoe Skyforest 56 Comments

If you want to coax more power out of your car’s engine, a turbocharger is a great way to go about it. Taking waste energy from the exhaust and using it to cram more air into the engine, they’re one of the best value ways to make big gains in horsepower.

However, unlike simpler mods like a bigger exhaust or a mild cam swap, a turbocharger install on a naturally aspirated, fuel-injected engine often requires a complete replacement of the engine management system, particularly on older cars. This isn’t cheap, leaving many to stick to turbocharging cars with factory tuneable ECUs, or to give up altogether. In the 1990s, aftermarket ECUs were even more expensive, leading many to avoid them altogether. Instead, enthusiasts used creative hacks to make their turbo builds a reality on the cheap, and there’s little stopping you from doing the very same today.

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SpaceX Drops The Ball On Catching Fairings

May 6, 2021 by Tom Nardi 91 Comments

You don’t have to look very hard to find another rousing success by SpaceX. It’s a company defined by big and bold moves, and when something goes right, they make sure you know about it. From launching a Tesla into deep space to the captivating test flights of their next-generation Starship spacecraft, the private company has turned high-stakes aerospace research and development into a public event. A cult of personality has developed around SpaceX’s outlandish CEO Elon Musk, and so long as he’s at the helm, we can expect bigger and brighter spectacles as he directs the company towards its ultimate goal of putting humans on Mars.

Of course, things don’t always go right for SpaceX. While setbacks are inevitable in aerospace, the company has had a few particularly embarrassing failures that could be directly attributed to their rapid development pace or even operational inexperience. A perfect example is the loss of the Israeli AMOS-6 satellite during a static fire of the Falcon 9’s engines on the launch pad in 2016, as industry experts questioned why the spacecraft had even been mounted to the rocket before it had passed its pre-flight checks. Since that costly mistake, the company has waited until all engine tests have been completed before attaching the customer’s payload.

SpaceX’s concept art for propulsive landing

But sometimes the failure isn’t so much a technical problem as an inability for the company to achieve their own lofty goals. Occasionally one of Musk’s grand ideas ends up being too complex, dangerous, or expensive to put into practice. For instance, despite spending several years and untold amounts of money perfecting the technology involved, propulsive landings for the Crew Dragon were nixed before the idea could ever fully be tested. NASA was reportedly uncomfortable with what they saw as an unnecessary risk compared to the more traditional ocean splashdown under parachutes; it would have been an impressive sight to be sure, but it didn’t offer a substantive benefit over the simpler approach.

A similar fate recently befell SpaceX’s twin fairing recovery ships Ms. Tree and Ms. Chief, which were quietly retired in April. These vessels were designed to catch the Falcon’s school bus sized payload fairings as they drifted down back to Earth using massive nets suspended over their decks, but in the end, the process turned out to be more difficult than expected. More importantly, it apparently wasn’t even necessary in the first place.

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Ask Hackaday: If Aliens Came By, Would We Even Notice?

May 6, 2021 by Al Williams 112 Comments

A few years ago we talked about the chance that the first known extrasolar visitor — Oumuamua — might be a derelict solar sail. That notion has been picking up steam in the popular press lately, and it made us think again about the chances that the supposed rock was really a solar sail discarded or maybe even a probe flying with a solar sail. At the same time, Mars is as close as it ever gets so there is a gaggle of our probes searching the red planet, some of them looking for signs of past life.

All this makes us think: if we did find life or even artifacts of intelligent life, would we realize it? Sure, we can usually figure out what’s alive here on Earth. But to paraphrase Justice Potter Stewart, “We know it when we see it.” Defining life turns out to be surprisingly tricky, recognizing alien technology would be even harder.

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