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Comment by saneshark | Hacker News Reader

While this seems promising it seems like it will be a short lived phenomenon. Missles will just become obsolete and then you have to come up with a deterrent for lasers.

Is anyone actively working on laser deflector shields?

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I don't get your reasoning? Lasers need line of sight and hit a very small area, missiles can travel long distances and hit a massive area.

Even taking out a small area in today's modern combat fighters would do serious damage, and travelling at the speed of light there isn't much that maneuverability or current defensive countermeasure can do to deter a laser.

Go high enough, and you can have LOS to anything within half the planet of you. Wait for the world to spin a bit, and you have LOS to the other half.

Perhaps the catch being that if you have LOS to half the planet then half the planet has LOS to you and presumably its a lot easier to build and operate a high energy laser on the ground rather than in high orbit.

Missile-launched laser platforms.

You don't have to loiter for all time.

Loitering in space is near-free.

That said, I'm thinking pumped-laser-tipped missiles could be very effective as e.g. anti-ship weapons. You could launch one straight up from your territory, and have it snipe the enemy ship from far away. The enemy would have to monitor a large portion of the sky for relatively small objects and react instantly with lasers of their own to counter that.

EDIT: I suspect these could be made into pumped-laser shells; good luck countering one that's launched from beyond the horizon.

Ships would appear to have access to an idea anti laser countermeasure - spray lots of water into the air!

Water is also a good RF screen, so such shield would also effectively blind and cripple the ship. Even discounting the energy use, no way they could keep that up continuously. Ramp-up time is probably large enough too (on the order of seconds), making surprise attacks very feasible. Not an ideal countermeasure, though I'm not sure what would be, beyond packing more ablative armor.

If you're in a position to be aware of an imminent attack, ramp-time is probably within reason. Power reqirements are fairly modest by military standards -- a small fireboat can pump impresive quantities of water, and since the goal in defence / obscuring is to blind (and absorb energy), a finer atomised mist would be more effective. Filter and system fouling is likely a bigger concern.

True bolt-from-the-blue attacks are rare, though possible.

The spray profile could be modified to enable sensor detection, or alternative (off-ship, buoy, balloon, drone, ...) sensor placement could enable both eyes and shields.

Fog or smoke generators also.

The terrain offers few concealment opportunities, though it is high ground. Sort of.

More high, less ground.

Is this a weird way of describing satellites?

Well, missiles tend to follow parabolas rather than orbits - apart from the Soviet FOBS, but that required a very large ICBM.

https://en.wikipedia.org/wiki/Fractional_Orbital_Bombardment...

Missile size varies generally with range. Tactical, short-range, cruise, and drone-based platforms can be modest and stealthy.

Suborbital missiles are not satellites.

So: no.

Might be that lasers will start showing up on missiles. Hard sci-fi has its missiles carrying nuclear-pumped X-ray lasers, but I suppose smaller, non-nuclear versions could do well enough for terrestrial use.

As for "laser deflector shields", we haven't cracked the "deflector shield" part yet. The closest thing we have to force fields is actual matter - in this case, probably kicking up a dense dust cloud to scatter the laser.

Missiles are an offensive weapon; these are defensive weapons (for shooting down missiles).

The lasers will probably remain, and missiles will get better and better penetration aids (stealth, reflective/ablative/insulating coatings, etc) to get past the lasers.

At even higher powers, lasers may outclass missiles as anti-aircraft weapons, but we're not nearly there yet. In the surface-to-surface realm missiles are more likely to be obsoleted by railguns than lasers.

Not necessarily. One of the more dangerous missions of the USAF is SEAD[1]. During Vietnam, the "Wild Weasels"[2] flew these daring missions where the gist was to get all enemy air defense to fire at them, so they could find them, and destroy them. Airborne based anti-missile lasers, such as this, would be utterly devastating for this. It would improve survivability of aircraft flying SEAD missions. SEAD is generally the first step (in US military doctrine) before total domination of the skys. I'd consider that a pretty offensive use of this technology.

[1] https://en.wikipedia.org/wiki/Suppression_of_Enemy_Air_Defen...

[2] https://en.wikipedia.org/wiki/Wild_Weasel

Sure, in the sense that power is generally fungible, these can be offensive. But they don't obsolete the weapons actually used to destroy the targets exposed during that SEADS mission.

I find this topic fascinating. As a defensive measure these could have immense value. I'm sceptical of any present long range value however.

The ballistic nature of artillery, missiles, and other projectiles allows hitting targets beyond the horizon. Lasers are uni-directional so whilst they would be great against targets in line of sight, I doubt you'll see laser weapon systems employed as long range weapons for a very long time.

Of course, you could deploy them from a platform like a satellite, or aircraft, but the power requirements are immense and any current day aircraft would probably be so large as to be a sitting duck. I recall they've carried out testing of this nature using a 747 as a test platform. Until they can make planes of that size more survivable, I guess we're stuck with defensive applications.

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