5 ms·
I will believe it when I see it. Focusing that much light on a small moving object, through layered and moving air, with an intensity to burn through metal wou
by sandworm101 5y ago
I will believe it when I see it. Focusing that much light on a small moving object, through layered and moving air, with an intensity to burn through metal would be an achievement. Burning through enough of that metal to degrade a falling rocket (as opposed to during boost phase of flight) is even harder. For all the talk about cost reduction, have a look at what realworld laser armor costs. Painting the nosecone of a rocket white, or coating it with reflective foil costs next to nothing but is remarkably effective.
Better question: What would this do to a manned aircraft? There is a reason there are treaties against blinding weapons.
- simplyaccont 5y ago>I will believe it when I see it. Focusing that much light on a small moving object, through layered and moving air, with an intensity to burn through metal would be an achievement. Burning through enough of that metal to degrade a falling rocket (as opposed to during boost phase of flight) is even harder. it's been working 20 years ago. it's just systems were too big. you needed 2-3 tracks to supply energy to laser system, and there were delays between shots. >For all the talk about cost reduction, have a look at what realworld laser armor costs. Painting the nosecone of a rocket white, or coating it with reflective foil costs next to nothing but is remarkably effective. doesn't work. nosecone it's small part of rocket, laser will target midsection probably. reflective foil won't help either as it needs to be designed to reflect specific wavelength of laser iirc
- sandworm101 5y agoAny foil will do, just as the JWST's sunshield is effective against all the wavelengths coming off the sun. Gold or silver is best, but aluminum foil from the grocery store is extremely reflective across all wavelengths we would call laser. Just giving the metal rocket a good polish would make a significant difference.
- simplyaccont 5y agothere is some difference, but I guess all the companies that sank billions into directed energy weapons missed that aluminum foil from shop can negate all their efforts
- weatherlite 5y agoI agree, as corrupt as some military industry can be, I highly doubt something dumb as aluminum foil can defeat the laser.
- chongli 5y agoAluminum foil reflects about 85% of visible light. Gold reflects 98% of visible light. Neither of these materials would be effective in protecting against a 100kW laser. That remaining 2% is 2kW of light energy directed at a small target. It’ll rapidly ablate the gold foil and then the target will begin to absorb the full power.
- awakeasleep 5y agoWouldnt the rocket continue moving towards its target during the ablation?
- chongli 5y agoThe goal of the laser is to destroy the electronic detonator inside the warhead. If the detonator is destroyed then the potential damage from the missile is reduced from catastrophic to manageable. With a 100 kW laser I think the whole process could happen in less than a second.
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- opwieurposiu 5y agoAt the current power level, this laser is mainly useful against drones. There is a limit to how much laser power you can shoot through the air. When the threshold for breakdown is exceeded, a high density plasma is produced which is opaque to visible and infrared wavelengths and thus absorbs the laser radiation. The moon does not have this laser power limit, but moving Tel Aviv to the moon would quite expensive and you would lose the mediterranean climate.
- derekp7 5y agoCouldn't you start of with a larger (meter wide) lens and focusing mechanism, so that it narrows down at the target? Then you aren't heating up most of the air between. Also what about high output short pulsed lasers? Couldn't you get much higher output for a brief enough duration that it wouldn't heat up the air?
- Miraste 5y agoSounds like that could be gotten around by using multiple lasers.
- sandworm101 5y agoMultiple beams creates a different problem. Say your beam is 1cm across and you are aiming at a 30cm target. All your energy is in that 1cm. You don't much care where in that 30cm it hits so long as it burns through. But with two lasers, to be effective, each beam needs to hit the same sport on the target. Instead of a 30cm target, laser #2 now has to hit the 1cm beam of the first laser.
- omegant 5y agoThat, or also you get a shotgun effect with different damaged areas in a single target. Increasing the probability of destruction with less powerful lasers.
- nekcihc 5y agoThose lasers do not burn through. #2 does not have to hit exactly the same place as #1 is heating up to boil electronics. No idea, what is meant under lasers in article, but what they were describing could be even be concentrated radio microwaves to fry electronics. There is no need to use concentrated heat to heat up a tea - your target is making a tea, not making a hole in kettle.
- CapitalistCartr 5y agoIt would need to pack the energy of a stick of dynamite (1 lb explosive weight) into a short burst of light.
- cobookman 5y agoWould it? If the laser is able to focus on the rocket for multiple seconds. Then it'd just need to pack a fraction of that energy over a sustained duration. Which sounds reasonable.
- CapitalistCartr 5y agoThe rocket is moving at perhaps mach 4+. The laser has to strike a singular spot. So holding focus for multuple seconds is an as-yet-unsolved problem. Of course, hitting an incoming missile at all is at the edge of current capability.
- adolph 5y agoI was interested in validating or invalidating the mach 4 number. I guess it depends on the specific rocket, but the 122 mm M-21OF-M Rocket, sometimes referred to as Katyusha (although that was the name of a specific launcher, not the rocket [0]) is 660 m/s or about mach 2 [1]. 0. https://en.wikipedia.org/wiki/Katyusha_rocket_launcher https://en.wikipedia.org/wiki/Katyusha_rocket_launcher 1. https://kintex.bg/product-4-77 https://kintex.bg/product-4-77
- CapitalistCartr 5y agoThat's a good example of the problem. That's about 660 meters per second. Instead of "multiple seconds", the laser has about 1/100 second to penetrate the skin. Of a missile that's shaking, twisting, rocking.
- lr1970 5y agoMost likely, a missile will be rotating about its axis of symmetry making illuminating a single spot possible only in a short pulse mode.
- propesh 5y agoIll never forget when the Iron Dome was first rolling out, this rocket researcher on the internet said it couldn't be done. He explained it pretty well, and I was convinced. Search google for Iron dome doesn't work (looking back to 2010-14) And yet, it does work (mostly). So basically what I'm saying, this stuff is hard, and few people in the world can even verify your claim, never mind have access to the tech or AI behind it. But i'd bet with the Israelis.
- propesh 5y agoHere is the article: https://www.technologyreview.com/2014/07/15/172055/an-explanation-of-the-evidence-of-weaknesses-in-the-iron-dome-defense-system/ https://www.technologyreview.com/2014/07/15/172055/an-explan... Again, not sure if this turned out to be correct; but from reading reports on the ground and the lives Israel claimed it saved (and building more of them,) it seems evident he was in fact wrong.
- trhway 5y agoHe seems to be just a theoretic, not an actual military nor weapons manufacturer. From the start his pondering about unimportance of hitting engine instead of warhead is already very wrong and very theoretic. It is also very theoretic wish to hit the rocket frontally, I mean it would be great, it is a wet dream of any air defense, yet on practice hitting sideway chasing from behind is more realistic and still works great usually.
- zokier 5y agoThis article has a video of similar system from Lockheed Martin in 2013 demonstrating successful destruction of missile https://blogs.timesofisrael.com/iron-beam-iron-dome-and-laser-defense/ https://blogs.timesofisrael.com/iron-beam-iron-dome-and-lase... The capability for lasers to counter rockets has been demonstrated over and over in the past 20-25 years. The problem has always been making the systems practical, but I guess they are getting there now.
- nine_k 5y agoAFAIK far enough infrared is not very efficiently reflected by white paint or by metallic foil. If you can lower the efficiency of the cover layer from 99.9% to, say, 80%, this may be enough to degrade the mirror layer, create a dark spot or a cloud of plasma. After that most of the radiant energy will be consumed by that spot, it will overheat and degrade everything around it, while also changing the aerodynamics of the object enough to veer it way off course.
- flyinglizard 5y agoMy understanding is this will be used right next to the Gaza border meaning it will get the rockets during boost phase. Iron Dome will still exist at the other end of the course to shoot down the remaining rockets.
- weatherlite 5y agoInitially maybe but the goal is to have protection for Israel's north and center from Iranian/Hezbollah missiles. Hamas isn't perceived as a major threat.
- deeviant 5y ago> Painting the nosecone of a rocket white, or coating it with reflective foil costs next to nothing but is remarkably effective. What information are you basing this statement on?
- 271828182846 5y agothe enemy might even shoot mirrored rockets just to reflect the beam and scorch what's below ...
- Protostome 5y agoTheoretically, the laser doesn't need to "burn" through the metal, i.e melting it. it only needs to heat it beyond or close to the detonation temperature of the fuel that powers the rocket.