Tag Archives: weapons

Saint Javelin: how do Ukraine’s anti-tank weapons work?

“Saint Javelin”. Image via Reddit / USMC.

Wars have always been a scientific wrestling match just as much as a brutal confrontation in the field. Soldiers rely on science to give them an edge over their opponents and nowadays, firefights are settled by work done in labs, design bureaus, forges, or universities long before the first shot is fired.

In days long past, technical differences pitted obsidian-wielding Incans against musket-armed conquistadors. Shipbuilders shaped empires. Those who knew how to build chariots trampled over those who did not. Shock cavalry ruled the battlefield of medieval Europe due to the simple stirrup, inherited from Asian invaders. Today, research and technical capability have never been as important in wartime.

Courage and grit keep people fighting, but aren’t much use against a 50-ton tank. Anti-tank missiles, however, are great against them. Big guns, too, tend to do the job. So while we dearly hoped that such weapons will never be necessary, looking at the situation in Ukraine… they still are. So here’s a rundown of the science behind modern anti-tank weapons, from simple cocktails to the more high-tech ones.

First off, the tank

T-90A main battle tank at the 2013 Victory Day Parade in Moskow, Russia. Image via Wikimedia.

To blow up a tank, you first need a tank.

There is no shortage of photographs or videos in the news today showing some type or another of armored vehicles using the blanket term ‘tanks’. Strictly speaking, this isn’t accurate. Tanks are specialized vehicles meant to perform certain tasks. A tank is defined by what it does and how it’s supposed to do it, not by its components or appearance. Broadly speaking, a tank has tracks, a big, long gun, a really big turret, machine guns poking out of it or on the turret.

Tanks are tracked, heavily armored vehicles, typically carrying heavy primary armament in an enclosed fully-rotatable turret, with secondary armament co-axial to the main weapon. Their role is to engage well-protected targets, other vehicles (especially other tanks), and exploit weaknesses in enemy lines using their mobility.

They do not perform any other role — they do not carry infantry or supplies, they do not provide indirect fire support, they do not work as combat taxis. Generally speaking, they do not carry missile launchers externally. These requirements necessarily inform the shape of tanks, imparting them with their advantages and their drawbacks.

This is not a tank, even if it has tracks, armor, a gun, and a turret. It is a Russian BMP-3 Infantry Fighting Vehicle. Image via Wikipedia.

Let’s start with the advantages. Tanks carry the thickest armor and heaviest armament among military vehicles today. They are exceedingly resistant to non-specialized weaponry and pack a mighty punch. Tanks can effectively engage any type of target in battle due to their range of weapon calibers and ammunition types. They are able to traverse virtually any type of terrain, they’re quite scary to anyone and everyone, and typically protect their crews from environmental hazards such as gas weapons.

As far as disadvantages go, tanks are very complex machines with a lot of moving parts. They require extensive and specialized maintenance procedures, crews, and parts. Tanks rely on a vast logistical network for fuel and ammo without which they are completely useless. They generally require extensive maintenance of their drive train after driving a relatively short distance on their own power and need a complete repair/replacement of said drive train after a few of these extensive maintenance procedures. Due to their extreme levels of protection, tanks offer exceedingly poor visibility for their crews, especially at very close distances. Because of this, tanks rely on infantry for defense and are completely helpless against close-in opponents without it. Their tracks are relatively delicate (compared to the rest of the tank) and vulnerable; tanks become immobile if even one of their tracks is broken or jammed. They are also expensive to produce, maintain, and use.

Now that we’ve seen what a tank is, let’s see how we can blow it up.

Kinetic weapons (tank guns)

The main type of kinetic shells used against tanks today is known as Armor-Piercing Fin-Stabilized Discarding Sabot (APFSDS) rounds. It’s a mouthful, but it’s hella effective.

However, because of the recoil they generate when firing and the size and weight of the explosives used to propel them, kinetic rounds are only used with guns, usually mounted on tanks. They are rods made of very hard, dense metals, such as tungsten or depleted uranium alloys. They are fired from a tank’s cannon and rely on speed and toughness to push through steel plates.

These shells are usually much thinner than the bore (diameter) of the gun they’re fired from, so they are mounted in supports called sabots, which are blown away upon firing. The fins keep them steady in flight to maintain accuracy.

APFSDS (bottom) used on Japan’s Type-90 tanks. The black collar is the ‘sabot’, made out of two halves that break apart after firing. Shell on top is a HEAT round. Image via Wikimedia.

Their working principle is quite simple: push a piece of harder metal through a plate of softer metal using high force (speed). The shells bounce around the tank doing a lot of damage after penetration. They also break apart the inside faces of the armor plates they hit (a process known as ‘spalling’), creating high-speed fragments that rip through crew and internal systems. APFSDS rounds do not carry any explosives; all the damage they do is caused by impact between the shell, armor fragments, and the soft insides of the tank.

Tanks today have their armor plates angled to promote APFSDS bouncing on impact. Other types of defense, such as explosive reactive armor (ERA), are also effective against the shells. Their main drawback is that they lose energy in flight and become less effective with distance.

Sabot releasing the shell after firing. Image via Gfycat.
Note the back of the sabot, used to transfer energy to the shell (push it) through the higher-diameter barrel. Image via Gfycat.

Still, they are the least high-tech weapons useful against tanks and still effective due to their simplicity, reliability, and the immense forces they bring to bear against targets. Ukraine’s tank corps uses this type of ammo on its armed vehicles, as most likely do Russian tanks, as well. Although many varieties are in use, as far as costs go, the US’s M829A3 APFSDS costs around $8,500 per round.

But they’re not what militia or the infantry would use when defending against such vehicles. The shoulder-mounted weaponry you see in videos from Ukraine rely on:

Chemical rounds

Anti-tank rockets and the infamous RPG work on a different principle. Instead of relying on mass and speed to pierce through armor, they use explosive warheads arranged in a certain way — known as ‘shaped charges’. Because they derive their energy from explosives, not mechanical force, they are also known as ‘chemical rounds’ as opposed to ‘kinetic’, speed-based, rounds.

HEAT round used for the Leopard 2 main battle tank (middle two). Note the hollow copper cone inside the warhead, with explosives (yellow) packed behind it. Image via Wikimedia.

These devices are used in civilian applications as well, but they were originally invented, and still used to, defeat tank armor. In military speak, they are known as high-explosive anti-tank (HEAT) rounds.

Shaped charges work using the Munroe/Neumann effect, which describes how energy from a blast can be focused into a single point. They contain an explosive mass behind a shaped copper cone. When detonated, the cone focuses the explosion into a narrow space. The explosive, in turn, pushes the copper out at extremely high speeds. The shape of the cone is calculated so that the end result is a beam of molten copper shooting out in front of the weapon. Basically, these rounds create a laser beam of molten copper in contact with armor.

Although they are called HEAT, they do not melt armor. The copper jet pushing out of the weapon creates immense pressure which simply digs through armored plates.

Shape charge during detonation. Via Makeagif.

Their main drawback is that the jet generated by such weapons is only effective over a small distance. As such, ERA is very effective against shaped charges, as is spaced armor and, to a lesser extent, sloped armor. Even sandbags or metal sheets can be effective in stopping such shells, by forcing them to detonate prematurely. Still, since HEAT rounds don’t need to go fast or be really big to be effective, they are widely used for anti-tank weapons for infantry, land and air vehicles, and drones.

Tanks can also fire HEAT ammo. The cost varies greatly depending on caliber and manufacturer. A US High Explosive Anti-Tank- Multiple Purpose round may cost between $1,500 to $4,000, depending on several factors.


The infamous RPG is the simplest type of shaped-charge weapon in use today, the single most widely-produced anti-tank weapon on the planet, and has served in virtually all conflicts since being designed by the Soviet Union in 1960. The RPG-7 is currently in production and in use with some 40 countries around the world and total production, figures are estimated to be close to 10 million units.

Image via min.news.

The RPG-7 is a shoulder-mounted, portable, reusable rocket-propelled grenade launcher (basically, a bazooka). It fires an unguided rocket-propelled projectile that can carry anti-tank, high explosive/fragmentation, or thermobaric warheads, in a low arc. They are very simple, very cheap, plentiful, and very rugged weapons — each launcher is a steel tube with iron aiming sights and a grip.

This weapon sees extensive use in Ukraine on both sides. It is easy to use, easy to care for, and useful for a wide range of situations, including tank-busting. Its simplicity, although a major advantage, also means that the weapon is more easily countered. It’s also the most widely-used weapon of its type, so it represents a sort of benchmark. Designers know that every tank will face an RPG eventually, and put a lot of effort to protect these vehicles from it specifically. Still, it is more than capable of downing even a heavily-armored modern tank in the right situation and is more than capable of piercing any metal plates that are not protected against shaped charges.

Schematic of an RPG round detonating in contact with an armored plate. Image via Gfycat.

The simplest RPG-7 warhead can pierce through 500 mm of tank armor and is relatively accurate up to 200m / 660 ft, although it can shoot up to a distance of 500 m / 1,640 ft. With a cost of only between $500-2000 per launcher and $100-500 per rocket, the RPG-7 is definitely the way to go if you’re blowing up tanks on a budget.


The Next Generation Light Anti-tank Weapon was a joint British-Swedish project started in 2002 to modernize Cold War-era infantry anti-tank weapons.

Its main advantage over weapons such as the trusty RPG is that it uses guided munitions. Another advantage it has is that it can be fired from enclosed spaces.

NLAW (Next generation Light Anti-tank Weapon) firing at the Otterburn ranges. Image credits Royal Navy Media Archive.

RPGs fire a big grenade with a rocket engine strapped to their back. These are not guided and the blast from the launch generates huge pressure behind the weapon, meaning it could seriously injure troops if fired inside a confined space. NLAWs fire actual missiles that have fire-and-forget guidage systems. This means that the weapon uses a passive tracking system — ‘predicted line of sight targeting’ — which points the missile to the predicted position of the target. The missile is first launched using a ‘low-powered ignition’ system, to make it safe to use indoors.

Unlike the other weapons on this list, the NLAW is not designed to ever touch its target. The rocket flies above an enemy tank and detonates one meter above it, sending a powerful pressure wave down on the vehicle. While that might not sound very damaging for the tank, it’s more than enough to pulp the crew inside. This approach allows the NLAW to target even vehicles that are completely hidden behind the cover.

According to reports in the field, it seems to be working quite well against Russian tanks.

Test firings of the weapon.
Testing of the damage produced by the weapon.

The weapon is not reusable, however. Once the rocket is fired, the launcher is disposed of. It offers a similar level of penetration to the RPG — 500 mm, up to a range of 1000 m / 3,300 ft). This makes its cost of roughly $26,000 / €24,000 quite a hefty proposition. However, considering that tanks generally cost in the millions, it could be a worthy investment.


This US-made rocket launcher has become a symbol of Ukrainian defiance and is the driving force that inspired this article. This 20-year-old weapon has been in use by the US military, alongside 20 allied nations. A lot of them have been supplied to Ukraine as military aid following the onset of hostilities, and more are planned to be sent there. Ukraine has received thousands of Stingers from countries all around the world to help it defend from Russian invaders.

US soldiers training with the Javelin missile launcher. Image via Pixabay.

Although no different in working principle than other anti-tank missiles, the Javelin is one of the most potent weapons of its kind currently employed in the conflict. What sets it apart from other portable launchers is that the Javelin missile is launched in a high arc, and programmed to slam down into enemy tanks from above.

Tank armor is thickest at the front and sides, where most shots are likely to impact. However, to keep the vehicles down to an acceptable weight, concessions have to be made somewhere — so designers put thin armor on their back, with extremely thin protection afforded to the undersides and the top of tanks. The Javelin’s trajectory is meant to take advantage of this design feature.

The explosion here is caused by ammo detonating inside the target. Quite devastating.

The missile is also guided, so it can track moving vehicles and ensure high hit probability. Like the NLAW, it is a fire-and-forget system: the soldier using it fires the weapon and can then scramble for cover to avoid return fire. Javelins also have an impressive effective range of up to 4 km / 2.5 miles, which helps a lot.

Live firing of the Javelin during exercises in Quatar, 2017, showcasing its use and range. Skip to 2:55 for the launch.

All of this, however, comes at a cost. A single Javelin system comes in at an eye-watering $80,000 / €71,000. This is very expensive for an infantry weapon, meaning they would be prohibitively expensive to field on-masse. In the arithmetic of war, one such missile is vastly cheaper than the tank it takes out. But this remains the most expensive anti-tank weapon a single soldier can carry into battle in the conflict, severely limiting its use.

The Molotov cocktail

A Molotov cocktail is essentially a bottle filled with fuel and an adhesive — it’s burning liquid that sticks to things.

While not technically an anti-tank weapon, Molotovs can be used against tanks and the Ukrainian Defense Ministry has told civilians to make Molotov cocktails to fight Russian tanks. The defense ministry even distributed a recipe for producing Molotov cocktails to civilians.

Molotovs were extremely efficient against tanks used in World War II but may have a harder time against more modern tanks, which are sealed better and more resilient. However, even if the Molotovs would leave the tank relatively unscathed, they could still be devastating to the driver on the inside of the tank.

We don’t often talk about weapons here on ZME Science, and it’s most definitely not a subject that brings us joy. In an ideal world, these weapons would only belong in the museum. However, we feel that given the ongoing situation, this is worth talking about.

These weapons are definitely not the only ones being used in the fields and cities of Ukraine. But they are among the most impactful. Although it’s tragic to see science embroiled in armed conflict and used to cause death and destruction, there is value in learning about the particular set of circumstances that conflict creates and the solutions we can develop to address them — even as we fight the realities of war and try to prevent such conflicts from happening.

For now, military technology and the science behind it are, unfortunately, a current subject. Hopefully, not for long.

Future weapons: Microwave weapons (like the ones from Star Wars) already exist in reality

Ever since sci-fi became a thing, sci-fi weapons also became a thing. Lasers, rayguns, microwave weapons, you name it, and someone wrote about it. Many of these are still fiction, but some are inching towards reality. Laser weapons, for instance, are already being tested by the US military and many speculate that they’re already close to being used. Something else that militarists are looking closely at are microwave weapons.

Image credits: Pixabay/pexels.

If there’s any big sci-fi franchise that’s been teasing weapons, it’s Star Wars. For half a century, the Star Wars universe has featured all sorts of crazy weapons (including your favorite lightsabers), but many of these don’t have any equivalent in the real world.

But that may soon change. Some recent weapon systems and defense experiments (conducted both in and outside the US) have successfully managed to demonstrate the use of high-powered microwave weapons technology.

The physics of microwave weapons stands up to scrutiny and according to defense experts, they can do a lot of damage. In theory, at least, a long-range microwave beam could cause severe damage to human brain cells and tissues, and make soldiers and other nearby people permanently blind.

What are microwave-based weapons and how do they work?  

Image credits: Francesco Ungaro/pexels

High-power microwave (HPM) weapons use focused electromagnetic energy beams (frequencies ranging between 500 MHz to 3 GHz) that can disable electronic systems, disarm air defense networks, and destroy enemy facilities. Such weapons are also called directed energy weapons (DEW), and they are able to release energy in the form of microwaves, laser beams, plasma, or sonic rays.

Microwaves are essentially a form of electromagnetic radiation. The wavelengths of microwaves range from one meter to one millimeter, and they work at a frequency between 300 MHz and 300 GHz. You can kind of tell that microwaves can do a lot of damage just by thinking about your microwave and how quickly it heats up your food or drinks. It does this by sending energy dispersed as molecular rotations and raising the temperature.

Your microwave weapon only works in a small enclosure, but microwaves can be used to transmit power over long distances — and this is the principle on which proposed microwave weapons would also work.

A powerful microwave weapon system has three main units: a pulse power source that produces high voltage electrical pulses; an HPM source that generates microwaves either from a linear electron beam (by converting the kinetic energy of electrons into electromagnetic radiation); or directly through impulsive sources such as electronic circuits; and finally, an antenna that allows the focus of high power microwaves on a target. 

Unlike conventional artillery units, microwave-based weapon systems do not require any physical ammunition but they do demand high amounts of electrical power, and they can also work with explosive chemicals as well.  

Promising developments in the field of microwave weapon technology

A prototype PHASR laser rifle. Image credits: US Air Force/Wikimedia Commons

In January 2019, a notice was released by the Department of Defence revealing that the US army is planning to create an Ultrashort Pulse Laser (USPL) system in order to advance its tactical capabilities and meet future warfare demands. USPL is a part of the department’s plans to modernize the army and on completion, it could become the most powerful laser-based weapon system ever made. 

However, USPL is not the only initiative that is concerned with the development of microwave weapons. Here are some similar programs and microwave weapons that exist in reality:

  • Rapid Capabilities and Critical Technologies Office (RCCTO) under the US Army has developed a Directed Energy-Maneuver Short-Range Air Defense (DEM SHORAD) system to shoot down enemy’s drone swarms and other hostile UAVs (Unmanned Aerial Vehicles). This laser-shooting system comes installed on Stryker vehicles and by 2022, RCCTO is planning to deliver at least four of these to the military. 
  • A 2018 report from South China Morning Post reveals that China has developed a lithium-ion powered laser rifle that can shoot invisible microwaves at the target and even make it catch fire. Being hailed as the laser equivalent of AK-47, this non-lethal assault gun is called ZKZM-500 and it is said to be used by the Chinese police and by the army in future covert military operations. However, many defence experts have raised doubts about the claims made by the Xian Institute of Optics and Precision Mechanics related to the range and laser-shooting abilities of ZKZM-500.  
  • European arms manufacturer MBDA is developing a laser weapon system named ‘Dragonfire’ that could be deployed on the warships owned by UK’s Royal Navy. This new LDEW (laser-directed energy weapon) system would be able to shoot several thousand-kilowatt powered lasers and provide defense against drones and other airborne enemy units. Recently, the British government also awarded military contracts worth $100 million to companies like Raytheon and Thales for the development of directed energy weapon systems.
  • A video uploaded by the US Navy in May 2020 shows a successful laser weapon test conducted at a San Antonio-class transport ship USS Portland. During the test, a 150 kW powered laser weapon system shoots an energy beam at a AV flying in the sky, the target catches fire as soon as it comes in contact with the beam and gets destroyed.
  • India’s Defence Research and Development Organization (DRDO) is working on a classified project named Durga II, which is actually a 100-kilowatt, lightweight directed-energy system. The organization plans to design Durga II in such a manner that it could be deployed anywhere from land-based military vehicles to aircraft and naval warships. 

Apart from these recent developments, countries like Russia, Australia, and Israel have also been developing their own microwave-based laser weapon systems. Some of those systems have been already deployed and others are in the testing or development phase.

Microwave weapons other than laser-based systems

An LRAD deployed at USS Blue Ridge. Image credits: Tucker M. Yates/Wikimedia Commons

When compared to traditional artillery, microwave weapons have many tactical advantages. For instance, microwaves when fired from a weapon hit the target without being affected by any external factors such as wind, weather, inertia, gravity, etc. Plus, the enemy soldiers can neither see nor hear any approaching microwave shots unless they have specialized microwave detecting sensors. Moreover, microwave weapons only require a power supply unit and no other heavy logistics or ammunition supply units during a mission.

These are the main reasons why countries and defense companies are spending millions of dollars on creating efficient microwave weapons. However, these aren’t the only types of futuristic weapons actively researched in the military field.

Other types of futuristic weapons

Sonic and ultrasonic weapons

These weapons release unbearable sound waves that can cause pain, intense headache, ear bleeding, eyeball vibration, and even permanent hearing loss. Sound cannons used by the police to control the crowd during a protest are also an example of sonic weapons, they operate on a frequency similar to microwaves. A sonic system falls in the non-lethal weapon category and is sometimes also referred to as a long-range acoustic device (LRAD).

Plasma weapons

Similar to Han Solo’s Blaster gun, plasma weapons are capable of firing bolts of plasma at the enemy. In physics, plasma is called the fourth state of matter which is formed by free ionized electrons and may contain some other subatomic particles as well. They are used to daze, burn, or warn the target but similar to sonic weapons they are also said to be non-lethal.

The Plasma Acoustic Shield System (PASS) being developed by Stellar Photonics for the US Army is one such plasma-based weapon system that would be capable of firing plasma shockwaves (both lethal and non-lethal) at the target.

Heat ray weapons

A DEW system, capable of increasing the surface temperature of a target and destroying the enemy’s electronic devices. It is designed for area security, port protection, and crowd control purposes and if a human is hit by a heat ray weapon, he or she may feel a burning sensation and intense pain in the skin. 

The US Military’s Active Denial System is a riot-control weapon based on heat-ray technology, it can fire microwaves up to a distance of 1000 meters and is used in both defensive and offensive field operations.

From laser-shooting planes to bullet-less plasma rifles and vibration-causing sonic guns, defense researchers are working on many insane microwave weapon ideas but only time will tell how many of those become a reality. 

Huge stash of abused Iron Age weapons discovered in a German hill fort

Researchers have just uncovered one of the largest stashes of Iron Age weapons ever discovered in Germany. Around 100 different artifacts have been recovered from the site.

Image credits LWL-Archäologie für Westfalen / Hermann Menne.

The advent of the Iron Age was an important stepping stone in our technological history. It was marked, quite unsurprisingly, by the introduction of iron as a material for tools and weapons. Iron-carbon alloys (what we refer to as ‘iron’) generally have similar properties to properly processed bronze (the metal it replaced), but iron has the huge advantages of being more abundant and simpler to produce, while having the downsides of requiring higher temperatures and more complex ore processing techniques.

At first, the use of it was quite limited, but as the know-how of smelting iron spread, so did its use. In Germany, the (early) Iron Age spanned between 800 to 45 BC, followed by the late Iron Age up until 1 BC, when the area became a Roman province. It was probably during the fighting for this transition that the stash was deposited at the site.

Stashed for a rainy day

The site is close to the German city of Schmallenberg, on the top of mount Wilzenberg. A press release by the Westfalen-Lippe Landscape Association, which made the discovery, explains that around 100 Celtic Iron Age artifacts were unearthed here.

This isn’t the first time the Wilzenberg site attracts academic interest. Work has been ongoing here ever since the 1950s. Prior digs have revealed a series of features suggesting that the site served as a hill fort back in the day, most notably ramparts. But there were some artifacts recovered over this time, as well.

Hillforts were relatively small fortifications made of local materials — from stone or wood to clay or soil — that were meant to discourage foreign incursions, or slow them down enough for a response to be mustered; hence, the ramparts. And, according to the findings, the Wilzenberg site also served as a weapon stash, most likely for locals or the soldiers manning the fort.

What prompted the discovery was the association’s use of metal detector devices to search for iron artifacts hidden beneath the structure’s former floor. Around 100 spears, swords, lance tips, belt hooks, and iron harness elements were discovered. Although dating them directly with sufficient accuracy proved impossible, the team explains that context cues would place the artifacts somewhere between the years 300 and 1 BC.

What was really peculiar about the finding is the condition the weapons here were uncovered in. Most of the swords here were severely damaged or deformed, being bent into halves or thirds, for example. Both the spears and lance tips were blunted. The team explains that the sheer scale of the damage seen here suggests this was an intentional, sustained effort. It was most likely carried out following a battle, as the victorious army wanted to prevent these weapons from being used again.

It’s also important to note that the weapons and artifacts were found piled up, not spread around, which indicates that they were carried to and deposited on the site. This suggests that the battle was fought elsewhere, and the weapons were then recovered, transported to Wilzenberg, damaged, and deposited here.

It’s very likely that the battle occurred around the city of Wilzenberg, and that the winners took these items as their trophy.

The original press release (in German) is available here.

Physical, encryption-like method could help the world finally get rid of nukes

MIT researchers have devised a method that could allow states to prove they’re disposing of nuclear weapons without giving away any of their technical details — which are considered state secrets.

Mark 5.

Open nose cavity US Mark 5 nuclear bomb showing the ‘pit’.
Image credits Scott Carson / US Atomic Energy Commission.

Nuclear disarmament negotiations (particularly those between the U.S. and Russia) always hit a patch of rough ground when verification processes come up. The main point of these talks is to promote nuclear non-proliferation — the understanding that the fewer nukes there are in the world at any one time, and the fewer actors there are with access to them, the easier it will be for humanity not to blast itself back to an irradiated stone age. However, every reliable verification process that the two parties could agree on as trustworthy (i.e. visually identifying the warheads) would give away technical data pertaining to the weapons.

This would never fly. For starters, governments don’t like other people to know how their nukes work — especially the people they’re generally aiming said nukes at. Secondly, such measures would risk disseminating technical details to third-parties, thereby defeating the whole purpose of disarmament efforts. Visual confirmation, then, became a no-go.

To spot a warhead

Now, an MIT research team reports developing a novel method of confirmation that could help promote nuclear disarmament without disseminating any state secrets. The method, similar to a physics-based version of cryptographic encryption systems, can be applied in two different versions — just in case one is found to have drawbacks by any government. The findings were published in two different papers.

Lacking a reliable tool to identify nuclear weapons, and thus bereft of a way to enforce their destruction, past agreements have focused on decommissioning of delivery systems. It makes sense, as it’s far harder to ‘fake’ a plane or a ballistic missile, whereas nuclear bombs are basically spheres of plutonium. Such measures have worked reasonably well up to now, but lead author Areg Danagoulian believes that it only skirted the real issue: to avoid such weapons falling into the hands of terrorist or rogue states, we need to dispose of the actual warheads — which means we need a reliable way to identify them or spot fakes, one to which governments will agree.

“How do you verify what’s in a black box without looking inside? People have tried many different concepts,” Danagoulian says. “But these efforts tend to suffer from the same problem: If they reveal enough information to be effective, they reveal too much to be politically acceptable.”

Their solution draws inspiration from digital data encryption methods, which alter data using a set of large numbers, which form the key. Without this key, the encrypted data is a hodge-podge of characters. However, while it may be illegible, it is still possible to tell if it is identical to another set of encrypted data — if they use the same key, the datasets would be the same hodge-podge. Danagoulian and his team applied the same principle for their warhead verification system — “not through computation but through physics,” he explains. “You can hack electronics, but you can’t hack physics.”

The method analyzes both of a warhead’s essential parts: the sphere of radioactive elements that supply its nuclear ‘gunpowder’, and the dimension of the hollow sphere called a pit that serves as a ‘detonator’ — details pertaining to both elements are considered state secrets. Because of this, they couldn’t simply probe the weapons’ internal characteristics, and they couldn’t tell a fake apart just by measuring emitted radiation.

Negative filter

So what the team did was to introduce a physical key, created from a mix of the same isotopes used in the weapon, but in a ratio unknown to the inspection crew. Similarly to a filter applied to a photo, the key will scramble information about the weapon itself. In keeping with that analogy, the physical key is like a complementary color filter (a picture’s negative) that will cancel out all of the weapon’s emissions when lined up properly. If the investigated object has a different emission pattern (i.e. it’s a fake), it will bleed through the filter, alerting the investigation crew.

Nuclear verification.

(Top) diagram showing the configuration that could be used to verify that a nuclear warhead is real. (Bottom left) measurement without the reciprocal. (Bottom right) measurement with the reciprocal.
Image credits Areg Danagoulian.

This filter — called a cryptographic reciprocal or a cryptographic foil — will be produced by the same country that made the warheads, thereby keeping their secrets safe. The weapon can be hidden in a black box to prevent visual inspection, lined up with the foil, then get blasted with a beam of neutrons. A detector will then analyze the output and render it as a color image — if the warhead is genuine, the image will be blank. The second variant of this process substitutes a photon beam for the neutron one.

These tests are based on the requirements of a Zero Knowledge Proof — where the honest prover can demonstrate compliance, without revealing anything more. It also benefits from a built-in disincentive to lie. Because the template is the perfect complement of the weapon itself, when superimposed over a dummy it will actually reveal information about the warhead’s composition and configuration — the very things states don’t want others to know about.

It’s a neat concept; the only issue I have with it right now is that it only works if all parties involved are genuine, and do actually create the right reciprocals for their warheads. Still, if the system does someday get adopted and helps bring about significant reductions in the number of nuclear weapons in the world, Danagoulian says, “everyone will be better off.”

“There will be less of this waiting around, waiting to be stolen, accidentally dropped or smuggled somewhere. We hope this will make a dent in the problem.”

The papers “Experimental demonstration of an isotope-sensitive warhead verification technique using nuclear resonance fluorescence” has been published in the journal Proceedings of the National Academy of Sciences; “Nuclear disarmament verification via resonant phenomena” has been published in the journal Nature Communications.

Sci-fi buffs everywhere, rejoyce! The UK military is developing laser weapons

The UK military is betting a lot of money on lasers. The Ministry of Defence has officially signed a £30m contract to produce a prototype directed energy weapon, to be tested by the end of the decade.

Image credits Patrice Audet / Pixabay.

Why go through the effort of producing bullets, boxing, transporting, then shooting them, when you can fire pure science at the enemy? That’s a question the UK Ministry of Defence is willing to pay £30m to answer. A consortium led by Stevenage-based missile company MBDA which includes QinetiQ, Leonardo-Finmeccanica, GKN, Arke, BAE Systems and Marshall has been awarded the contract to build the prototype for the laser weapon system, named “Dragonfire”.

Ahead of the curve

The contract has been in the making for a few months now, but the MoD has finally put the seal of approval on the consortium. Delivery of the prototype is expected for 2019, when the military will test its ability to lock onto and track targets at various distances in all weather conditions for land and water applications.

The MoD’s endgame goal, however, is loftier than “Dragonfire” alone — they want to know if ‘energy’ could become the next ‘ammo’. As Peter Cooper of the UK’s Defence Science and Technology Laboratory (DSTL) said:

“This is a significant demonstration program aimed at maturing our understanding of what is still an immature technology.”

“It draws on innovative research into high power lasers so as to understand the potential of the technology to provide a more effective response to the emerging threats that could be faced by UK armed forces.”

MBDA spokesman Dave Armstrong said that the project will propel the UK to “the forefront of high energy laser systems”.

“Furthermore, it advances the UK towards a future product with significant export potential, as well as providing opportunities for partnerships with other nations’ armed forces that have similar requirements,” he added.

Harriet Baldwin, the Minister for Defence Procurement, thinks projects such as this one will “keep this country ahead of the curve”. But this isn’t the first time a country has toyed with the idea of directed energy weapons. The US has been experimenting with laser weapons for decades now. Their efforts culminated with the testing of a weapon dubbed ‘Laws’ on the USS Ponce in the Arabian Gulf in 2014. The system successfully targeted a small boat directed towards the ship and shot down a small drone. Still, no-one has had the technological oomph to bring such guns on the front line up to now.

If it proves itself reliable, weapons such as the Dragonfire could be used to take down drones, jets, or strategic missiles, as well as point defense systems against mortar shells, missiles, roadside bombs and various other threats.

Bringing a laser to a knife fight

Laws Gun

The Laws system during tests in 2014.
Image credits John F. Williams / US Navy.

The MoD said that the weapon isn’t being developed to counter any specific threat, only to see what advantages such weapons could bring to their armed forces. But with growing global instability, tensions rising in eastern Europe, and Russia’s much publicized recent improvements in armament and weapon systems (such as the RS-28 ICBM, dubbed ‘Satan 2’), the Dragonfire could have a more specific purpose in mind than simple research.

I’ve always been a military technology buff, and I nerd out over anything from copper daggers to tanks, battleships, and Star Destroyers — and the Dragonfire is bound to be a solid piece of technology and applied science. But no matter how much I’ve enjoyed the laser-drenched dogfight scenes in Star Wars, I can’t help but feel saddened to see science twisted into destroying things and killing people. Especially in a time when disarmament and working together to solve greater problems should come at the forefront.

But the contract is signed and the proverbial wheels are turning. Time will tell if the Dragonfire will turn out to be just another straw, or a lit match, thrown in the haystack.

Weapons shouldn’t be able to decide themselves to end a life – Hawking, Musk, Wozniak sign letter requesting the ban of autonomous weapons and military AI

One of the cornerstone events in Frank Herbert’s fictional Dune Universe is the Butlerian Jihad – an empire-wide crusade against thinking machines and AI of any kind.

Jihad, Butlerian: (see also Great Revolt) — the crusade against computers, thinking machines, and conscious robots begun in 201 B.G. and concluded in 108 B.G. Its chief commandment remains in the O.C. Bible as “Thou shalt not make a machine in the likeness of a human mind.”

A militant group, calling themselves the Titans, used humanity’s over-reliance on technology to gain dominion over the entire human race. They transplant their brains into mechanical bodies and become immortal and nearly unstoppable, enslaving human kind. Granting too much power over their computerized empire to the AI Omnius, they are overthrown by it. The rogue program sees no value in human life, and the deaths it causes makes humanity rise up in revolt and, after their final victory, ban AIs and computers forever.

A photo from the ‘Campaign to Stop Killer Robots’ which called for a pre-emptive ban on lethal robot weapons in 2013.
Image via observer.com

The tale has all the makings of a great story – a hero you feel for, humanity as underdogs and overbearing robot overlords. And, according to many researchers, programers and tech experts, it may have something even more important, that every good story needs.

It may have a kernel of truth

Elon Musk and Stephen Hawking have both previously warned of the dangers of advanced AI. Musk said that AI is “potentially more dangerous than nukes,” while Hawking was far more optimistic, merely saying that AI is “our biggest existential threat.”

The two have added their names to those of a very large number of scientific and technological heavyweights, that have signed an open letter which will be presented at the International Joint Conferences on Artificial Intelligence (IJCAI) in Buenos Aires tomorrow. Noam Chomsky, the Woz, and dozens of other AI robotics researchers have also signed the letter, calling for the world’s governments to ban the development of “offensive autonomous weapons” to prevent a “military AI arms race.”

Most of the letter addresses the issue of today’s “dumb” robots, vehicles and munitions being turned into smart autonomous weapons. Cruise missiles and remotely piloted drones are ok, the letter says, because they cannot make the choice to destroy or kill by themselves, as “humans make all targeting decisions.”

So where do we draw the line?

The letter voices the concern of may scientists that weaponizing AIs is a slippery slope that could very well lead to our extinction. The development of fully autonomous weapons that can fight and kill without human intervention should be nipped in the bud, scientists agree. And it letter warns us that once the first AI is weaponized, many more will follow:

“The key question for humanity today is whether to start a global AI arms race or to prevent it from starting. If any major military power pushes ahead with AI weapon development, a global arms race is virtually inevitable, and the endpoint of this technological trajectory is obvious: autonomous weapons will become the Kalashnikovs of tomorrow,” the letter reads.

Later, the letter draws a strong parallel between autonomous weapons and chemical/biological warfare:

“Just as most chemists and biologists have no interest in building chemical or biological weapons, most AI researchers have no interest in building AI weapons — and do not want others to tarnish their field by doing so, potentially creating a major public backlash against AI that curtails its future societal benefits.”

The letter is being presented at IJCAI by the Future of Life Institute. It isn’t entirely clear who the letter is addressed to, other than the academics and researchers who will be attending the conferences. Perhaps it’s just intended to generally raise awareness of the issue, so that we don’t turn a blind eye to any autonomous weapons research being carried out by major military powers.

The main issue with AI in general, and autonomous weapons in specific, is that they are transformational, game-changing technologies. Once we create an advanced AI, or a weapons system that can decide for itself who to attack, there’s no turning back. We can’t put gunpowder or nuclear weapons back in the bag, and autonomous weaponry would be no different.

There will always be Ix and Tleliax.

To tie the Dune parallel in a neat little bow and bring it to the end, the planets Ix and Tleilax in the fictional universe design and produce technology that was outlawed by the Butlerian Jihad, but is tolerated by the Empire, a kind of technological “gray-area”.

And the same issue stands with the letter. The history of global technology regulation warns us that making this kind of statement is much easier than realising what it asks for. What do we ban, how do we make sure the ban sticks? The thousands of scientists that have signed the letter to ban military use of AI may have inadvertently created restrictions on their own ability to share software with international collaborators or develop future products.

As Patrick Lin, director of the Ethics & Emerging Sciences Group at California Polytechnic State University, told io9.com:

“Any AI research could be co-opted into the service of war, from autonomous cars to smarter chat-bots… It’s a short hop from innocent research to weaponization.”

The LaWS system installed on the destroyer. Image: US NAVY

Laser weapon demonstrated aboard US Navy ship – the weapons of the future

Shells and bullets have evolved significantly in the past couple hundred years since they were first used, but in principle they’ve remained the same – discharge an explosive to propel a projectile. The 21st century might finally make way to a new class of widespread weaponry based on lasers. These are powerful, much more accurate than any explosive projectile and can work in virtually any weather conditions, as demonstrated by the US Navy’s latest deployment of the Laser Weapon System (LaWS).

The LaWS system installed on the destroyer. Image: US NAVY

The LaWS system installed on the USS Ponce. Image: US NAVY

The laser gun was test fired in a couple of rounds held from September to November aboard the USS Ponce (LPD-15) in the Arabian Gulf. In the video released to the public by the Navy, the laser can be seen destroying tiny targets placed far away on a moving attack boat and even a flying drone. Because of its tracking system, moving targets can be swiftly destroyed with pin-point accuracy. At 30 kilowatts or about 30 million times more powerful than your handheld pointer, this baby packs a punch! If you play on a Xbox or Playstation, with just a bit of additional training you could operate this laser yourself since a similar controller is used to operate it.

Because its power and mode of operation can be adjusted, not all targets necessarily need destroying. The LaWS can be used to dazzle pilots or enemy operators or deactivate sensors or other electric components, such as those found in an aircraft, without effectively destroying them. It’s also useful in tandem with conventional heat-seaking missiles, as the laser can be used to heat a target and make the infrared locking easier.

The optical system inside the LaWS. Image: US NAVY

The optical system inside the LaWS. Image: US NAVY

According to the navy, sailors working with the new weapon reported it worked “flawlessly, including in adverse weather conditions” and that it has exceeded expectations for reliability.” Officials were careful to note that this was not a test – the mounted laser is fully operational and battle ready. “If we have to defend that ship today, we will [use the laser] to destroy a threat that comes,”  Rear Admiral Matthew Klunder, the chief of naval research, said in a press conference at the Pentagon on Wednesday.

The laser's control system

The laser’s control system. Image: US NAVY

Besides accuracy, another advantage of the LaWS is its cost. The cost of launching a missile from a destroyer can cost up to $2 million, while the flyway cost of the laser system is just the price of the electricity it takes to power the device – 59 cents per shot. It’s true that the laser cost $40 to put in operation, but because the USS Ponce is one of the oldest ships in the navy’s fleet, it had to come with a separate power source. If integrated inside a modern ship, the laser would power directly from its local grid significantly reducing costs. Also, since this is a prototype, costs could be scaled down when mass produced.

Of course, you still need missiles to sink enemy destroyers. A laser could do that too – you only need to ramp up the power. A 150-kilowatt version of the laser – five times as powerful as the one mounted on the Ponce – is currently in development.