Sergey Brin’s airship aims to use world’s biggest mobile hydrogen fuel cell

Friday, March 5th, 2021

Sergey Brin’s secretive airship company LTA Research and Exploration is planning to power a huge disaster relief airship with an equally record-breaking hydrogen fuel cell:

A job listing from the company, which is based in Mountain View, California and Akron, Ohio, reveals that LTA wants to configure a 1.5-megawatt hydrogen propulsion system for an airship to deliver humanitarian aid and revolutionize transportation. While there are no specs tied to the job listing, such a system would likely be powerful enough to cross oceans. Although airships travel much slower than jet planes, they can potentially land or deliver goods almost anywhere.

Hydrogen fuel cells are an attractive solution for electric aviation because they are lighter and potentially cheaper than lithium-ion batteries. However, the largest hydrogen fuel cell to fly to date is a 0.25-megawatt system (250 kilowatts) in ZeroAvia’s small passenger plane last September. LTA’s first crewed prototype airship, called Pathfinder 1, will be powered by batteries when it takes to the air, possibly this year. FAA records show that the Pathfinder 1 has 12 electric motors and would be able to carry 14 people.

That makes it about the same size as the only passenger airship operating today, the Zeppelin NT, which conducts sightseeing tours in Germany and Switzerland. The Pathfinder 1 also uses some Zeppelin components in its passenger gondola.

The job listing is for “an experienced Hydrogen Program Manager to help us build a ‘lighter than air’ flight vehicle in Mountain View, CA, or Akron, OH.” The USS Akron Was the world’s first purpose-built flying aircraft carrier and the world’s largest helium-filled airship. It was destroyed in a thunderstorm off the coast of New Jersey on the morning of 4 April 1933, killing 73 of the 76 crewmen and passengers, the greatest loss of life in any airship crash.

Hydrogen does seem like a natural airship fuel.

Wood can easily be turned transparent to make energy-saving windows

Tuesday, February 16th, 2021

Apparently wood can easily be turned transparent to make energy-saving windows:

The standard process for making wood transparent typically involves soaking the wood in a vat of sodium chlorite — a chemical compound used in some bleaches and toothpastes — to remove a structural component of the wood called lignin. However, this takes a lot of chemicals, produces liquid waste that is tough to recycle and can weaken the wood.

Liangbing Hu at the University of Maryland and his colleagues came up with a method that modifies the lignin instead of removing it completely. It is quicker and uses fewer materials than the standard lignin-removal process, and also leaves the wood stronger.

The researchers’ method stems from the recent discovery that lignin can be made transparent by removing only the parts of its molecules that give them their colour. They brushed hydrogen peroxide, which is often used as a disinfectant, over the surface of the wood and then left it under a UV lamp designed to simulate natural sunlight. After soaking the wood in ethanol to remove any remaining gunk, they filled the pores in the wood with clear epoxy, a step that is also part of making lignin-free transparent wood.

The final product is a piece of wood that allows more than 90 per cent of light to pass through it and is more than 50 times stronger than transparent wood with the lignin completely removed. “The transparent wood is lighter and stronger than glass. It could be used for load-bearing windows and roofs,” says Hu. “It can be potentially used to make a see-through house.”

This tokamak produces magnetic bubbles called plasmoids that move at around 20 kilometers per second

Sunday, February 14th, 2021

A new type of rocket thruster proposed by a physicist at the U.S. Department of Energy’s (DOE) Princeton Plasma Physics Laboratory (PPPL) would apply magnetic fields to propel plasma:

The new concept would accelerate the particles using magnetic reconnection, a process found throughout the universe, including the surface of the sun, in which magnetic field lines converge, suddenly separate, and then join together again, producing lots of energy. Reconnection also occurs inside doughnut-shaped fusion devices known as tokamaks.

“I’ve been cooking this concept for a while,” said PPPL Principal Research Physicist Fatima Ebrahimi, the concept’s inventor and author of a paper detailing the idea in the Journal of Plasma Physics. “I had the idea in 2017 while sitting on a deck and thinking about the similarities between a car’s exhaust and the high-velocity exhaust particles created by PPPL’s National Spherical Torus Experiment (NSTX),” the forerunner of the laboratory’s present flagship fusion facility. “During its operation, this tokamak produces magnetic bubbles called plasmoids that move at around 20 kilometers per second, which seemed to me a lot like thrust.”

[...]

Current plasma thrusters that use electric fields to propel the particles can only produce low specific impulse, or speed. But computer simulations performed on PPPL computers and the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility at Lawrence Berkeley National Laboratory in Berkeley, California, showed that the new plasma thruster concept can generate exhaust with velocities of hundreds of kilometers per second, 10 times faster than those of other thrusters.

(Hat tip to Jon Jeckell.)

Cyberpunk came true

Thursday, February 4th, 2021

Cyberpunk no longer feels like “the future”, Noahpinion suggests, because the cyberpunk writers of the 80s were just too good at predicting the future:

Much of the stuff they imagined is now just the stuff you see in the news.

In 2021, the Russian government hacked much of the U.S. government and many U.S. companies. Remotely piloted drones are defeating human forces on the battlefield. A whistleblower who exposed government electronic surveillance programs communicates from his foreign exile by telepresence robot. Artificial intelligences beat the best humans at the most complex board games and trade in financial markets. Information warfare and espionage are just standard tools of politics now. Animated singers are sex symbols. Militaries train in virtual reality. Online currencies are worth hundreds of billions of dollars and are used in shadowy underground economies and cybercrime. Computer interfaces are being implanted into pigs’ brains. A blind man can now see thanks to synthetic corneas.

All of these elements are recognizable as staples of 1980s and 1990s cyberpunk science fiction, or close relatives thereof. The cyberpunks anticipated the future of technology to an almost eerie degree.

Instead of realizing its own Sputnik moment, it is triggering one in China

Tuesday, January 19th, 2021

The US responded to the rise of the USSR and Japan by focusing on innovation, Dan Wang says, but so far the US is responding to the technological rise of China by kneecapping its leading firms:

So instead of realizing its own Sputnik moment, it is triggering one in China.

This year, the US doubled down. It produced two rounds of novel restrictions on Huawei, threatened wider restrictions on Tencent and ByteDance, forced the sale of TikTok to a US consortium, and limited technology exports on SMIC, DJI, and dozens of other companies. Aside from Alibaba, it’s hard to name many big Chinese tech firms that have not faced sanctions or the threat of one from the US.

The actual effects of these regulatory actions have been uneven. Designation to the entity list hasn’t always had a major impact on every company’s operations. Federal courts have tied up the bans on Tencent’s WeChat and ByteDance’s TikTok. At the same time, Huawei is trying to work through major difficulties, especially in its smartphone business. TikTok, China’s most successful tech export, still might be sold off. And more generally, Chinese firms are starting to be locked out of developed markets. Lack of access to the richest and most discerning consumers makes it more difficult to make the best products in the world.

The US can revel in Huawei’s pain. But its actions have not been costless to itself. By withholding components that Chinese companies have relied upon, the US government has turned American firms into unreliable suppliers. These restrictions can sometimes block non-American firms from making sales too. In an extraordinary assertion of extraterritoriality, the US declared in August that any company, anywhere in the world, needs to apply for a license to sell a product to Huawei if it is produced on the basis of US technologies.

Nothing can be easier to destroy than trust. Chinese companies have responded by de-Americanizing their supply chains because they have no choice. US politicians can observe the sometimes-devastating impacts of sanctions. What they don’t seem to realize — or want to believe — is that they’re simultaneously pummeling the American brand writ large. I’ve documented for Dragonomics the uncomfortable questions American companies tell me they’re starting to face on whether they can credibly be long-term suppliers. Elsewhere, the Economist has reported that even poultry farmers in China are wondering if they’ll be able to import baby chicks from the US. And there are now multiple reported instances of Japanese companies marketing themselves as more reliable than their American competitors. Moreover, I hear growing unease from companies in the rest of Asia and Europe on buying American. Can everyone really be sure that this denial campaign will be limited to a handful of bad Chinese actors? Or is a better model of the US government that once it has found a fun new toy, it will keep playing with it until it is no longer fun?

With these regulations, the US has initiated one of the greatest and strangest antitrust actions ever, against potentially all American exporters. The US Treasury has for years expressed worry about the potential decline of the dollar’s dominance following excessive use of blocking sanctions. This fear is turning into reality for the real economy. One might expect alarm bells to be going off in DC, but it doesn’t appear that there’s much pushback against these regulations, except for murmurs from trade associations. It’s possible to defend these moves as correct — for example by justifying that the costs on American firms are worth it for the chance to slow Huawei down right now — but the government does not appear to have had a vigorous debate about the tradeoffs. Instead, the strategy seems to be a result of bureaucratic kludges, pushed forward by whichever faction has the upper hand, made mostly because the financial sanctions office has resisted dealing a serious blow to Huawei in a single stroke.

For the most part, the control hawks faction of the government has had a run of the table, shown by the fact that US agencies have been more focused on taking down Chinese firms than extending US strengths. At a time when it’s more important than ever to advance its semiconductor companies, the government is crippling their sales to their largest or fastest-growing market. When research capabilities at US universities need to grow, the government is denying them students. And when the US should be attracting more talent to its shores, the government has made it more difficult for people to immigrate. Thus the US looks committed to a strategy to destroy the scientific and industrial establishment in order to save it.

Meanwhile in China, these actions have triggered a surge of interest in mastering technology. For the first time arguably since the industrial rise of Japan in the 1950s, a major country is committed to thinking deeply about the invention of its own tooling. A whole generation of scientists and engineers must examine foundational problems like to build leading tools (like lithography machines) and create the best materials (like wafers and chemicals). And the state is fully behind that effort. After steady calls from Xi throughout the year to master technology, the Central Economic Work Conference announced in December that science and technology work will be the top priority in 2021; the conference has never broken science and technology out as an independent item, never mind give it top spot.

China used to have something quite similar to Twitter

Wednesday, January 13th, 2021

China used to have something quite similar to Twitter, Spandrell explains:

It started as an outright clone, later evolved on its own, quite interesting way. I’m talking of Weibo.

Weibo started in 2009, and a year later already had 100 million users. Chinese people are very online, and they very much enjoy the sort of casual, easy dopamine release that comes from microblogging. The Japanese are also avid Twitter users, incidentally, while they never had much of a blogosphere. The language also helps: 150 Chinese characters amount to about triple that in English, so you can say quite a lot.

As usual in China, there’s little regulations, and little enforcement of existing regulations, so once Weibo came in it was very free and open. It was the first national forum of public opinion that the Chinese had ever seen. It became huge almost instantly, and of course the most popular part of it was political debate. Everyone and their mother had become a political pundit on Weibo, rather amusingly forgetting they lived in a Communist single-party state. For a couple years people shat on their mayors, their governors, this or that politician, this or that policy, or even the Communist party itself. The American Embassy joined the party with their famous Air Quality reports (at the time air quality in China was really awful and the government refused to release figures), which were promptly retweeted by 300 million boomers with added comments on how much better America was at everything.

Well that situation couldn’t last. China was at the moment undergoing a rather big leadership transition (Xi Jinping assumed power in late 2012), so the massive agitation going on at Weibo went on undeterred. But governments, certainly the Chinese government, might be slow, but once they get moving they’re unrelenting. In 2013 China decided to crack down on free speech on Weibo, and crack down they did. Famous accounts which had been too edgy politically got visits by police, if not outright arrested. Some were jailed, others had to make public proclamations of loyalty to Socialist values. We’re talking of people with tens of millions of followers; China is a big country.

Once the big guys were dealt with pour encourager les autres, the masses were targeted with the beginning stages of what has now become a very sophisticated apparatus of keyword censorship. In Weibo today you just can’t search what you want. If there’s a rumor that Xi Jinping has farted this morning, the word “fart”, “frt”, “f4rt” and all permutations that might come up are all promptly banned from searching at any sizable Chinese social media. That’s step 1: stop the thing from going viral. Step 2 is deleting already existing mentions of the fart. The thing. That takes time but they have an army of censors (which Weibo was forced to hire at their expense) to take care of that. Step 3 is banning you from tweeting about the fart, but that’s a last resort, as it’s the most annoying and harder to implement.

Soon enough Weibo just became unusable. Most people up there were on the platform precisely to shitpost on politics, to be edgy, to shit on the government, to be a viral pundit, retweeted by 50 million people at least once in their lives. The new regulations were so oppressive that most people just left. Not to some other similar platform. There had been some at the beginning but they all lagged off and eventually were killed, and the government wouldn’t allow a new microblogging site. When Weibo was censored people just left, period. They abandoned the public square. They mostly retreated to WeChat, the national instant messaging app. Some didn’t get the message and started being edgy on their public statuses, but most just retreated to private chat groups, where they could be safe from the prying eyes of government. The public square was killed, on purpose, and it never recovered.

Well, not quite. After politics were banned from Weibo, only the most inane stuff was allowed to remain. Mostly celebrities and PR accounts, and the odd clueless boomer. But it’s been years now, so plenty of people who need an easy internet exposure but have no intention to talk politics are still on Weibo, many producing quite decent content. A lot of aspiring intellectuals have also learned what is politically correct and what not and have managed to survive. Plenty still get banned mercilessly after some innocent mishap though, as Carl Zha (by all indications a paid propagandist for the government) who lost 10 million followers after dissing some Chinese fighter jet or something. But the platform is lively again, if in a more boring, sanitized way. Half a generation of youngsters have grown up without knowing what legal shitposting was like, and so just don’t do it. You can’t miss what you’ve never known.

Now, America isn’t China, so there’s no guarantee that the situation will evolve in the same way. Maybe Parler or Gab manage to survive the multi-pronged assault by every single part of the tech stack, and they thrive as a hotbed of right wing activism. I don’t find it very likely though. I see Twitter becoming a sanitized platform where only government-approved speech is allowed, and most people will be fine with that. I’ll stay on Twitter if only to follow a bunch of academic linguists who I find interesting. Also Japanese Twitter has its charm, as Twitter censorship is much, much weaker in exotic languages.

So to recap: I think we should do what the Chinese did, which is retreat to private groups. So go to Telegram, to Urbit if you’re smart.

Its potential as an explosive was not recognized for three decades

Thursday, December 24th, 2020

I recently stumbled across a reference to toluene, and I couldn’t help but think, how hard is it to transform toluene into trinitrotoluene, or TNT? (Which has an interesting history…)

TNT was first prepared in 1863 by German chemist Julius Wilbrand and originally used as a yellow dye. Its potential as an explosive was not recognized for three decades, mainly because it was too difficult to detonate and because it was less powerful than alternatives. Its explosive properties were first discovered by another German chemist, Carl Häussermann, in 1891. TNT can be safely poured when liquid into shell cases, and is so insensitive that it was exempted from the UK’s Explosives Act 1875 and was not considered an explosive for the purposes of manufacture and storage.

The German armed forces adopted it as a filling for artillery shells in 1902. TNT-filled armour-piercing shells would explode after they had penetrated the armour of British capital ships, whereas the British Lyddite-filled shells tended to explode upon striking armour, thus expending much of their energy outside the ship. The British started replacing Lyddite with TNT in 1907.

The process for making TNT is simple, but not easy:

In the laboratory, 2,4,6-trinitrotoluene is produced by a two-step process. A nitrating mixture of concentrated nitric and sulfuric acids is used to nitrate toluene to a mixture of mono- and di-nitrotoluene isomers, with careful cooling to maintain temperature. The nitrated toluenes are then separated, washed with dilute sodium bicarbonate to remove oxides of nitrogen, and then carefully nitrated with a mixture of fuming nitric acid and sulfuric acid.

It’s possible to travel all around the world and never leave AirSpace

Saturday, December 12th, 2020

Digital platforms like Foursquare are producing a harmonization of tastes across the world:

Every time Schwarzmann alights in a foreign city he checks the app, which lists food, nightlife, and entertainment recommendations with the help of a social network-augmented algorithm. Then he heads toward the nearest suggested cafe. But over the past few years, something strange has happened. “Every coffee place looks the same,” Schwarzmann says. The new cafe resembles all the other coffee shops Foursquare suggests, whether in Odessa, Beijing, Los Angeles, or Seoul: the same raw wood tables, exposed brick, and hanging Edison bulbs.

It’s not that these generic cafes are part of global chains like Starbucks or Costa Coffee, with designs that spring from the same corporate cookie cutter. Rather, they have all independently decided to adopt the same faux-artisanal aesthetic.

[...]

We could call this strange geography created by technology “AirSpace.” It’s the realm of coffee shops, bars, startup offices, and co-live / work spaces that share the same hallmarks everywhere you go: a profusion of symbols of comfort and quality, at least to a certain connoisseurial mindset. Minimalist furniture. Craft beer and avocado toast. Reclaimed wood. Industrial lighting. Cortados. Fast internet. The homogeneity of these spaces means that traveling between them is frictionless, a value that Silicon Valley prizes and cultural influencers like Schwarzmann take advantage of. Changing places can be as painless as reloading a website. You might not even realize you’re not where you started.

It’s possible to travel all around the world and never leave AirSpace, and some people don’t.

This is where the drones came in

Monday, November 30th, 2020

Before the war, on a tactical level the Armenian army was superior to the Azeri army:

It had better officers, more motivated soldiers, and a more agile leadership. In all previous wars with Azerbaijan, this proved to be decisive. But Azerbaijan found a way to work around it. This is where the drones came in: they allowed the Azeris to reconnoitre first the Armenian position and then the placement of reserves. Armenian positions then could be extensively shelled with conventional artillery, weakening their defences. Drones then guided the onslaught towards the Armenian reserves, bringing in artillery, multiple-rocket systems with cluster munitions, their own missiles, or using Israeli-made LORA ballistic missiles to destroy bridges or roads linking the reserves with the front. Once the Armenian side was incapable of sending reserves into battle, the Azeri army could move in any number it wished to overwhelm the isolated Armenian positions. This procedure was repeated day after day, chipping one Armenian position away each day and resupplying artillery during the night.

This tactic also worked well in mountainous territory the Armenians thought would be easy to defend. In the mountains, there is only one road connecting the front to the rear, which made it even easier for drones to spot targets. When the battle over Shusha demonstrated that the Armenians would not stand a chance even in this territory, the Armenian army started to disintegrate and Yerevan had no choice than to agree a ceasefire on adverse terms.

Plot-fusion is essential to detecting small and low-observable targets such as advanced drones or stealth aircraft

Saturday, November 28th, 2020

One of the military lessons from Nagorno-Karabakh is that computers and networks matter:

Like in Syria and Libya, Russian air-defence systems proved to be ineffective against small and slow drones. This has inspired a debate in the West about whether Russian air-defence systems are generally overrated. But this verdict would be premature.

Armenia’s most ‘modern’ air-defence systems, the S-300PT and PS series and the 9K37M Buk-M1, were both developed in the 1980s. While the missiles are still potent, their sensors are designed to detect, identifiy and track fast-moving fighters, and their moving-target indicators disregard small, slow drones. Like many 1980s systems, a lot of computing is predetermined by hardware layout, and reprogramming requires an extensive refit of the entire system, which the Armenians had not done. These systems are also incapable of plot-fusion: accumulating and combining raw radar echoes from different radars into one aggregated situation report. Plot-fusion is essential to detecting small and low-observable targets such as advanced drones or stealth aircraft. None of the export versions of Russia’s air-defence systems that it has sold to Syria, Turkey, North Korea, and Iran are capable of plot-fusion. (In the latter two cases, these are disguised as ‘indigenous’ systems like the Raad or Bavar 373.) There is therefore a huge difference in performance between Russian air-defence systems protecting Russian bases in Armenia and Syria and those Russian air-defence systems exported to Armenia and Syria.

Azerbaijan’s drones roamed free because Armenia had no jammer able to interrupt the signals linking the drones to their guidance stations. Only in the last days of the war did Russia use the Krasukha electronic warfare system based at the Armenian city of Gyumri to interdict Azeri deep reconnaissance in Armenia proper. Still, the Azeris also used the Israeli Harop loitering munition, which was able to work under adverse conditions (although at reduced effectiveness) as it does not, unlike drones. require a guidance link. Hence among armies that are likely to prepare to fight wars in the future – not only the US, China, Russia but regional powers such as Turkey, Israel, and South Africa – this experience will certainly prompt further research into artificial intelligence and autonomous lethal weapons systems. Rather than banning this class of ammunition by a prohibitive arms control treaty, as envisioned by Europe, they will experiment with how to make use of the new technologies and best integrate autonomous lethal weapons systems into their combined-arms manoeuvre forces, thereby increasing their operational tempo and effectiveness.

The information war has been just as fierce as the actual war

Thursday, November 19th, 2020

The information war has been just as fierce as the actual war in Nagorno-Karabakh, with both sides posting daily combat footage to proclaim victories:

Disinformation and propaganda, spread through official and unofficial accounts, have made it difficult to objectively assess the course of combat thus far. Furthermore, the relative accessibility of combat footage — whether from drones, cellphones, or cameras — paints a stylized picture of the battlefield for any analyst. They are official propaganda, and it is worth noting that on the modern battlefield, some systems have cameras or live video feeds, while many do not, distorting perceptions on combat effectiveness. A social media feed composed largely of drone video footage could lead one to believe in the dominance of such systems, even in a conflict where many casualties are still inflicted by armor, artillery, and multiple launch rocket systems. This tactical footage has led to familiar debates on the utility of tanks, the prowess of drones on the battlefield, or the proliferation of sensors.

There is a thirst for drawing lessons from contemporary conflicts that feature modern weapon systems. However, the result is often generalizing from a few cases, and at times, learning things that are not true. What can be discerned from this war is hardly revelatory. Remotely operated systems offer the utility of tactical aviation, close air support, and precision guided weapons to small nations, and to even relatively poor countries, for a cheap price. They saturate the battlefield with disposable sensors, shooters, and sensor-shooter packages in the form of loitering munitions. Notably, they enable precision artillery and strike systems to engage fixed positions, as has been seen across modern conflicts from Ukraine to Syria. Furthermore, tanks are vulnerable to counters, as they always have been, but it is unclear what other vehicles offer a better combination of firepower, protection, and maneuverability on the battlefield.

The war illustrates that in an offensive, or counter-offensive, the only thing worse than being in a heavily armored vehicle is being outside of one. If anything, the tank appears to be the most survivable vehicle, given the small warheads on drone carried munitions. These munitions often disable or mission kill the vehicle, but the crew can still survive anything other than a direct hit. Much of the hand-wringing in Western circles that comes from watching these conflicts stems from the epiphany that there is no way to avoid casualties on the modern battlefield, especially among an expensive force, replete with boutique capabilities that cannot be lost in large quantities. Furthermore, the ratios of support to maneuver units are important. Compared to forces like the Russian military, Western ground units feature poor availability of air defense and electronic warfare, and the expectations that existing air defenses or tactical aviation may be easily adapted to counter unmanned systems are probably unfounded. Armenia’s performance illustrates this problem. Drones are relatively cheap, and this military technology is diffusing much faster than cost-effective air defense or electronic warfare suitable to countering them.

That said, Azerbaijan’s unmanned air force has been operating against an opponent with incredibly dated short-range air defenses which are neither suitable nor effectively employed to defend against drones. Armenia does not have layered air defense, effective electronic warfare, or a large amount of tactical aviation. It has situated its air defense systems in relatively exposed fixed positions, in a mountainous region where air defense is even more difficult by virtue of the terrain. In truth, both sides are demonstrating tactical deficiency in their offensive and defensive tactics. While attaining some kills using optical sights, Armenia’s modernized Soviet systems (essentially technology that dates back to the early 1970s) were never meant to engage combinations of small drones, loitering munitions, precision artillery, or unmanned combat aerial vehicle systems. More advanced air defense capabilities like Tor-M2s are few, and have been intentionally held in reserve, although Azerbaijan has been reticent to use its fixed wing or rotary aviation. Armenia’s older S-300PS systems appear to have had no role in the conflict, and some launchers may have been destroyed early on, having never even been deployed.

The lessons from this conflict are consistent with those of other wars in the latter 20th century: It is much better to have a smaller ground force that is well defended from the air, than a vast armored force that is completely exposed to sensors and airpower from above. Well prepared defenses, if insufficiently protected or camouflaged from the air — which is increasingly difficult — are naturally vulnerable. The diffusion of remotely operated systems will outpace that of air defenses or specialized counter-drone systems, rendering older generations of air defense largely obsolete. Drones and loitering munitions will be, for some time, cheaper to acquire than the requisite defenses. And one can distribute forces, but they should be concentrated for assaults. There is no way getting around canalizing terrain, at least not until the battlefield features hover tanks. That tanks are vulnerable to anti-tank weapons should come as no surprise, but other vehicles, which trade survivability for maneuverability, seem to fare no better against anti-tank guided missiles. Vulnerable or not, it is unclear what other vehicle can achieve the tank’s mission on the battlefield.

Any conflict in space will be much slower and more deliberate than a Star Wars scene

Saturday, November 14th, 2020

When considering how to control space , Rebecca Reesman and James Wilson lay out the ways in which space combat is counter-intuitive for policymakers and strategists:

Satellites move quickly, but predictably:  Satellites in commonly used circular orbits move at speeds between 3km/s and 8km/s, depending on their altitude. By contrast, an average bullet only travels about 0.75km/s. They are here, and then gone.

Space is big: The volume of space between low-earth orbit and geostationary orbit is about 200 trillion cubic kilometers. That is 190 times larger than the volume of Earth.

Timing is everything: Within the confines of the atmosphere, airplanes, tanks, and ships can nominally move in any direction. Satellites do not have that freedom. Due to the gravitational pull of Earth, satellites are always moving in either a circular or elliptical path, constantly in free-fall around the Earth. Getting two satellites in the same spot is not intuitive. Therefore, it requires careful planning and perfect timing.

Satellites maneuver slowly: While satellites move quickly, space is big, and that makes purposeful maneuvers seem relatively slow. Once a satellite is in orbit, it requires time and a large amount of delta-V to perform phasing maneuvers.

Given all of this, for engagements in space, maneuvers and actions will have to be planned far in advance, Reesman said in an interview. “Any conflict in space will be much slower and more deliberate than a Star Wars scene,” she said. “It requires a lot more long-term thinking and strategic placement of assets.

[...]

Radio signals can be used to jam an opponent’s satellites, or spoof them by sending harmful commands. This would be an extension of electronic warfare already used in naval and air battles.

Some nations, such as France, have gone so far as to talk about deploying weapons in space to protect their own satellites. However, the authors suggest that satellites using kinetic weapons to shoot down opposing satellites seems unlikely for now, given the extraordinary energy required to maneuver an orbital weapon into a proper trajectory. More likely would be a “T-bone” collision between satellites, which does not require plane matching but rather occurs when two orbits cross.

Nations do have a strong incentive to not destroy other satellites because of the potential to create hazardous debris that would potentially affect all nations’ assets in space—and debris generated in space has a lasting effect. However, in the immediacy of war, a nation may decide it is worth permanently losing access to some slots in geostationary orbit, due to debris, in order to win a ground-based war.

The Army wants the first casualty of the next war to be a robot, not a human being

Thursday, November 12th, 2020

The Army wants the first casualty of the next war to be a robot, not a human being:

Army studies of recent conflicts — Russia vs. Ukraine, Armenia vs. Azerbaijan — show you can have a dramatic impact by adding a small infusion of 21st century tech to a largely Cold War force, [Maj. Gen. Patrick] Donahoe said. How? One approach the Russians have employed to devastating effect is to use drones to spot targets for rocket launchers. Likewise, while the US Army is developing a host of new missiles, armored vehicles, and aircraft, most units will be using Reagan-era hardware for years to come. In essence, Donahoe wants to organize these existing weapons in new formations and add drones and ground robots to scout ahead.

[...]

Historical data on direct-fire engagements “shows that our enemies generally shoot first 80 percent of the time,” Sando said. “We don’t like those odds, [so] we want to avoid the close fight if we can. If we can’t avoid it, we want to enter it under conditions that are favorable to us.”

But how? Current Army doctrine prescribes “making contact with the smallest element.” In layman’s terms, if you must stumble upon the enemy and get shot at (the formal term for this is a, “meeting engagement”), then do it with the smallest vanguard possible, giving the main body time to prepare and maneuver without being pinned down. In the future, Donahoe said, the goal will be to make first contact with an unmanned element.

Cold War doctrine envisioned engaging the enemy along what’s called the Forward Line Of Troops, or FLOT. In the new concept, according to a briefing at the conference, a Forward Line Of Unmanned Aerial Systems (FLUA) will fly ahead through no-man’s-land into enemy-held territory, followed by a Forward Line Of Robots (FLOR) on the ground, followed in turn by the Forward Line Of (Human) Troops. The unmanned systems will flush out the enemy, stumble into meeting engagements and ambushes, take and receive the first hits, and map the enemy position for the human troops coming along behind them.

Of course, the Army can’t do this today. To execute the concept in reality, they need a lot more unmanned systems, so they’re going to build them.

The sails will be made of steel and composite materials

Friday, November 6th, 2020

The Oceanbird transatlantic car carrier being designed by Swedish shipbuilder Wallenius Marine will be the world’s largest wind-powered vessel:

With capacity for 7,000 vehicles, the 650 foot-long vessel is a similar size to conventional car carriers, but it will look radically different. The ship’s hull is topped by five telescopic “wing sails,” each 260 feet tall. Capable of rotating 360 degrees without touching each other, the sails can be retracted to 195 feet in order to clear bridges or withstand rough weather.

The sails, which will be made of steel and composite materials, need to be this size to generate enough propulsive power for the 35,000-ton ship.

Although “the general principles of solid wing sails is not new,” designing the Oceanbird’s sails has been a challenge, says Mikael Razola, a naval architect and research project manager for Oceanbird at Wallenius Marine.

That’s because these are the tallest ship sails that have ever been constructed. “This ship, at the top of the mast, will be more than 100 meters (328 feet) above the water surface,” says Razola. “When you move up into the sky that much, wind direction and velocity change quite a lot.”

To better understand the atmospheric conditions at this height, Wallenius mounted sensors on top of its existing vessels, while they were crossing the Atlantic, and gathered data on wind velocity and veer (a clockwise change in wind direction), up to 650 feet above sea level. “All of this information has helped us design an efficient wing and hull system, that can make the most of the power available in the wind,” says Razola.

Oceanbird Car-Carrier

It won’t be completely emission-free, however, because it will still rely on engines for manoeuvring in and out of ports and for emergencies.

With a projected top speed of about 10 knots, Oceanbird will be slower than standard car carriers, which can travel at 17 knots. It will take around 12 days, instead of the standard seven, to cross the Atlantic.

NDB uses graphite nuclear reactor parts that have absorbed radiation from nuclear fuel rods and have themselves become radioactive

Thursday, September 10th, 2020

Nano-diamond self-charging batteries could disrupt energy as we know it;

NDB uses graphite nuclear reactor parts that have absorbed radiation from nuclear fuel rods and have themselves become radioactive. Untreated, it’s high-grade nuclear waste: dangerous, difficult and expensive to store, with a very long half-life.

This graphite is rich in the carbon-14 radioisotope, which undergoes beta decay into nitrogen, releasing an anti-neutrino and a beta decay electron in the process. NDB takes this graphite, purifies it and uses it to create tiny carbon-14 diamonds. The diamond structure acts as a semiconductor and heat sink, collecting the charge and transporting it out. Completely encasing the radioactive carbon-14 diamond is a layer of cheap, non-radioactive, lab-created carbon-12 diamond, which contains the energetic particles, prevents radiation leaks and acts as a super-hard protective and tamper-proof layer.

To create a battery cell, several layers of this nano-diamond material are stacked up and stored with a tiny integrated circuit board and a small supercapacitor to collect, store and instantly distribute the charge. NDB says it’ll conform to any shape or standard, including AA, AAA, 18650, 2170 or all manner of custom sizes.

(Hat tip to Hans G. Schantz.)