I run (and write) SDR (software defined radio) applications. Fairly high data rates are involved with continuous, real-time RF recovery; 16 mb/sec continuous isn't unusual. The kinds of gaps I see in wifi connections cause all manner of problems. Ethernet is simply more reliable. Especially as distance from the wifi node increases. I can remote SDR hardware up to 100 feet with no trouble on the usual cat cable on a 100 mb/sec network without problems, even when the network is pretty busy oitherwise. At these data rates, high reliability connections are of paramount importance.
Here, it's keyboard, (mouse is wireless to internal bluetooth), Powermate, card reader, SDR1, SDR2, microscope, webcam, midi control surface, weather station, train controller.
Plus these more-or-less regular "visitor" devices: DSLR, HD Video camera , USB memory sticks, iPad.
I have 6 USB ports on my early 2008 series mac pro, and it's not enough. So I use a powered hub as well.
I'm not sure how many would be "enough" fast USB ports, given the space limitations of a normal tower case. But it would be way more than six!
Most of my custom control stuff -- lights, security system, salt tank aeration and filtering, antenna rotors, a couple other SDRs, gate locks and opener, sump monitor and AC power monitoring -- are now ethernet, most courtesy of various Raspberry Pi installations. Then there's the commercial stuff: the AV system, the DVR, the game machines, roku and appletv,
Ethernet is better for me, Distance, number of clients, tons of utilities for diagnosis and monitoring, and the speed is decent.
Friend, if you let people get close enough to your hardware to muck with your thunderbolt connector, you didn't have any security anyway.
Restriction of physical access is an absolute first-level requirement for any kind of data / hardware security. Without it, you have nothing. And they have anything they want. There are no exceptions. Absolutely perfect, hardware-based Fingerprint lock? Just open the computer -- with a torch or diamond saw if required -- and walk away with the drives; read and/or decode 'em at your convenience.
Physical access means you have already 100% given up on security; you either trust everyone who has such access 100%, or you must actively restrict them somehow during such access -- guards, monitored cameras, etc.
As I understand it presently, there's no ethernet on USB-C. That's really disappointing. I have applications that require the higher dependability of ethernet as opposed to wifi. And the whole USB to Ethernet dongle thing... that tends to not work so well, at least thus far. There's also the additional security of not being OTA, where anyone in range can intercept your packets.
I'm all for as wireless as possible -- charging, etc. -- but I really don't think it's a good idea to remove the hardwired network connection. Particularly in that ethernet is so well supported across the board.
You're trying to analyze an entire microeconomy using only one product.
No, actually, I'm not. This is just my most current effort. I produce quite a bit along these lines, and my experience has been pretty uniform. I mention this last one because it is the most current, and so relates to the extant circumstances best.
Getting apoplexy at mention of the word "free" is Scrooge McDuck syndrome
Good thing no one is doing that, then, eh? Well, except for the moderators, but hey, it's slashdot, the kids in the basement have to have something fun to do!
It seems fairly clear that you didn't write that software for financial gain, so why did you write it?
That's right. I wrote it because none of the apps in this particular area did what I wanted to do. So I did it myself. I shared the results, and I got some additional value because the users made suggestions that were also useful in the context of my own use of the software. Plus, I'm cheered that others are getting some use out of it.
Is the fulfilment of your original desires not valuable to you?
Of course. But you're missing the point: most people can't afford to dedicate the kind of time I put into that thing; there are bills to pay, and where you might like to be coding GamerGoo for free, turns out the landlord isn't particularly impressed with your zillion "likes" on Facebook.
I only put my experience up there to show that free work is pretty much taken as free work. If you want money, you need to go commercial. That whole "support for money" thing? All that really means is you made bad documentation, or no documentation. Or a configuration file nightmare. I can't see charging people because the docs are poor or the program doesn't work easily and/or well. Really great apps work pretty much right away, and they are either intuitive to use, or are well explained so that they can be made intuitive to use. That takes time; time, for most people, is a net drain on cash reserves or worse, a way to go deeper into debt. I don't recommend the "free" path to anyone who isn't doing it without a concern for making a living from it.
The fact that the return is very likely to be zero is why I generally don't put a 'donate' button on software I release. I
Yes, same here.
In the end, the ego boost is worth more than the few bucks I might have made.
I don't care about ego boost, but I do like the idea that my work is assisting someone in some way. For me, the more people I can see using it, the more I'm motivated to work on it.
If this exciting new thing called “free” keeps going in the right direction, everyone still in the race gets a leg up.
Everyone but the people who wrote it, that is.
The problem with winning one's "15 minutes of fame" is that it won't pay the bills.
Which is why this exciting thing called "free", outside of an economy of plenty where it costs nothing to live, or where the author(s) operate(s) under essentially the same conditions, isn't always such a great deal for the author(s).
I have a free [donations accepted, but not nagged for] product out there with about 15k of regular users, and the income from it is as near zero as can be without quite being zero. To date, thirteen people have stirred themselves to donate. The product, however, tends to be used every day or two by those I call "regular users." I know because when it starts, it checks in with my website to see if there is an upgrade [always free], and when it does, I log a "start" to that IP, so I can generate some excellent stats on usage.
There are quite a few competing applications that perform the key functions mine does; but all do it a bit differently, and mine is one of the most feature-rich ones out there. So I have at least some reason to think that the users continue to use it because they find it at least adequate. The feedback I get tends to be quite kind, though that may just be a consequence of not wanting to annoy the author, I suppose. In any case, the considerable work I put in seems to have some value based on all this, and that value has not come back to me in any significant proportion. I can afford it -- don't get me wrong, I was not surprised by this, nor am I inconvenienced -- but that is because I produced pure commercial products for years first.
My all wheel drive Subaru gets [27 MPG], so I'm doing as well for pollution as driving an electric car.
You may be doing as well on average right now, assuming you're in an area that matches the average in terms of mass generation emissions, but one of the key advantages of an EV is that because it takes its power from the mass generation system after conversion, it is 100% fuel-agnostic. It doesn't know, and it doesn't care. In an area that is generating power from hydro, for instance (as is the case where I live), the regional contribution to CO2 from mass power generation is zero; and in this type of area, you are not doing better, you are doing (far) worse.
In addition, as more non-emission sources (wind, fission, fusion, solar, hydro, tidal, geothermal and so on) come online to replace the emitters, the EV's that were contributing by using mass emissive power transition, without any effort on the owner's part, into zero-present and future emissions vehicles. Your vehicle, however, will continue to emit until the day it cannot run any longer.
How about flags? It's windy as heck here, and putting up a flag is about as easy as anything ever gets. You get a lot of motion, at least in this neck of the woods.
how do they differentiate from bad gut flora causing obesity and people who eat way too many carbs have bad gut flora because of it?
It's not a problem. If they can get rid of the bad gut flora, then they just observe what happens, that's all.
If the person goes back into a state where eating those carbs or volume of food in general does not result in weight gain/maintainance, then the flora were the cause, not the consequence. If the weight stays on / continues to increase, then it wasn't the flora.
The thing to note here is that some metabolisms allow some people, regardless of level of activity, to eat and eat and eat and they don't gain. We know this. So we also know there's some kind of metabolic difference. The thing research is looking for is what that difference is.
If (and it's a big if) those with slower / more efficient metabolisms can be brought into the same metabolic ranges as those without, then there are major health benefits to be had, assuming there are no other side effects, of course.
I'm sorry, are you saying it'll be rotating with the pointy end down?
Up or down. Likely it'll be rotating, because that makes no particular difference to the steering mechanism, it's trivial to see to, and it's a free way to distribute laser energy. Not tumbling.
I think maybe you're underestimating the power of a 30kW beam collimated to a few square inches of area when fire through a mile of thick atmosphere
I'm just assuming there will be a reasonable polish on the surface, good enough to reflect 99% or better of the incoming beam, which leaves about 300 watts applied to the target, which it can't keep steady on, due to atmospherics, target movement (the aforementioned rotation plus vibration unless it's in vacuum) and incidental atmospheric heating / distortion.
Go look at that truck. It wasn't set to reflect much of that energy at all. It also wasn't moving. It also has a decent angle of incidence to the beam. It was also going through 1 mile of atmosphere, rather than 300 to 600 miles of atmosphere, and *that* assumes the target passes directly overhead and you have a *perfect* shot at it. Likely, it won't, and you won't, and the amount of atmosphere will be much greater. 30 kw isn't much in such a scenario. I don't think it'd work.
My understanding is that ICBM RVs are very aerodynamic (sharp cones)...I'm also not sure disrupting the airframe of an RV is much use.
Oh no, of course not. Not the RV. The rocket airframe, pre-release. If you're going to shoot a laser at a missile, the warhead isn't a reasonable target.
I still don't think you could hope for much more than disabling the warhead in the RV
I don't think that's even remotely possible with a 30 kw laser. You'd need a kinetic kill of some kind if you couldn't deliver at least another couple of orders of magnitude with a laser. You want 30 kw well collimated on target after 99% reflection to almost instantly disrupt the reflective surface (ablate it, most likely), which would take about 3 mw. For 30 kw... who would design an RV or a MIRV or a MIRV/RV with such delicate stuff in front or on the surface? Why would there even be a need to? The barometer could be anywhere (so you'd put it in the rear, and inside some heavy protection), likewise the logic package. You *might* manage to disable guidance fins, presuming that's the tech in use, but even so, you still have a live ballistic incoming that's going to go off as designed, albeit perhaps somewhat outside the predicted CEP.
If you're going to actually stop an ICBM from going off, you need to do so before it drops its last stage and reaches its programmed apogee. Things get pretty automatic and pretty unsophisticated once the thing begins the arming sequence, and all the easy-to-blow-up stuff has been left behind.
hopefully not spreading too much isotopic matter all over the place
Compared to the thing actually detonating (we're almost certainly talking multiple megatons here, quite likely double-digit), a core that doesn't even fizzle is no threat at all. Of course, if it does fizzle you're going to get a low yield nuclear explosion on the order of several tens of kilotons (basically it'll act like a small fission weapon instead of a large fusion weapon.) But the odds don't favor enough of the right kind of compression occurring, and anyway, 10-20 kt is highly preferable to 1-40 mt, so you shoot it down if you can.
Oh, it definitely is in the case of an ICBM. Anywhere within the atmosphere, the missile will be shaking. A lot. Randomly. Very likely it will be rotating about its long axis as well, in or out of atmosphere, so you'd have to track across the short axis at the rotational speed, then wait for the spot to come around again (while it is also cooling off, if it isn't in a hard vacuum at the time.) The atmosphere between the emission and the target will be turbulent, both naturally and as a result of incidental heating from the beam, and this will serve as an optical lens, moving the beam off target (high speed laser pulses can avoid this with a very fast double pulse: One to blow the atmosphere out of the way, and one to hit the target through the hole. However, 30 kw isn't enough for that, not even close.) Beam collimation is also very important, and the atmosphere fouls that up as well. The larger the area the beam covers when it hits, the lower the energy per square inch is, and the less local heating occurs (or conversely, the more local heat dissipation can be effective.) So you can't fix this by making the spot bigger (decreasing collimation.)
All these factors work together to interfere with the delivery of energy to one well defined region on the skin.
I suspect that in these cases, a kinetic kill is far easier and more reliable. Blow off a cloud of lead pellets in front of the missile, let it run into them, it's finished. Such an intercept missile can self-guide and actively measure distance to target which can significantly reduce misses, and it can compensate somewhat for its own velocity forward by shooting the cloud backwards so it stays in front of the incoming missile longer. Using a cloud of pellets reduces the need to be spot-on. At ICBM speeds, just one pellet is likely to incur completely fatal damage to the incoming missile's airframe. If you significantly disrupt the airframe's streamlining, it will self-destruct due to structural overload. And at these speeds, "significant" doesn't amount to very much.
No useful cooling? At hundreds of miles per hour of atmospheric passage? Hmmm. Not sure I can buy that. A few fins collinear with the forward-back axis of the craft and you'd have quite a bit of cooling.
You are making a LOT of assumptions. All of these matter: Ability of the mirror to dissipate energy prior to ablation or meaningful distortion. Collimation of the beam. Reflectivity of the mirror at the laser frequency. Ability of the laser to stay on target, and for how long. Distance from the laser. Atmospheric clarity and particulate density. Atmospheric turbulence. Disruption from atmospheric heating.
CIWS targeting is, as the acronym hints, "close in." You should think of the distance between the shooter (of anything) and the target as a lever. A tiny pivot at one end of the lever (the weapon's aim) translates to a "much" larger motion at the end of the lever (the point of impact.) Tolerances that will work at 100 yards aren't anywhere near close enough to work at many miles, or hundreds of miles in the case of missiles not aimed particularly at you (so you can be sure they will get close enough to hit.)
There are other issues. That truck was relatively close, between 1 and 2 miles ("more than a mile away"). To hit an ICBM at apogee, even it it goes right over you, you are going to have to spend a lot of energy on atmospheric heating, and you'll lose even more to atmospheric distortion. We're talking 300 to 700 times the distance, depending on exactly what "more than a mile away" actually means. But it is certain that 30 kw at the source will not equate to 30 kw at the target at those distances. So now the problem becomes more than "hit the target", it is also "stay on target for X time", and that assumes that enough energy can be delivered to overcome the missile skin's ability to dissipate it. Because if you can't do all those things, you can't hurt the missile.
Also, the odds of it going right over you kind of suck.
I"m pretty sure a regular mirror would not be employed.
But here's some hand-wavy math.
If a mirror reflects 99% of the light that hits it at the laser frequency (remember, there's only one frequency to be covered), and the light that hits it can heat proportional to 30 kw (however one figures that), then the mirror is absorbing a 300 watt equivalent and reflecting the rest unless the reflective surface fails.
If the reflective surface is highly heat conductive and the beam isn't all that tightly collimated, likely it won't flinch at all. Like any impact, the effect is all about how much energy you can shoehorn into the smallest possible area. If the beam is ~1/3 of an inch on target, then given 99% reflectivity, it's effectively 1 kw / square inch. If the beam is 1/30th of a square inch on target, it's 30 kw/square inch absorption after reflection. So it makes quite a difference. I think.
Anyone who works with lasers and mirrors, feel free to step in and correct or expand.
1) is if the laser is in visible light or not. If you can't see the red dot source a mile off, you can't evade it.
Pretty sure if you "see the red dot a mile off", the location where your eye was is just the steaming, goo-surrounded beginning of a well-cauterized hole that completely transits your head. Assuming tight collimation. With a broader 30 kw beam, your head would explode (steam pressure), and with a really broad beam, you'd turn into a human crisp before you had time to think "Hey! Las..."
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I run (and write) SDR (software defined radio) applications. Fairly high data rates are involved with continuous, real-time RF recovery; 16 mb/sec continuous isn't unusual. The kinds of gaps I see in wifi connections cause all manner of problems. Ethernet is simply more reliable. Especially as distance from the wifi node increases. I can remote SDR hardware up to 100 feet with no trouble on the usual cat cable on a 100 mb/sec network without problems, even when the network is pretty busy oitherwise. At these data rates, high reliability connections are of paramount importance.
Here, it's keyboard, (mouse is wireless to internal bluetooth), Powermate, card reader, SDR1, SDR2, microscope, webcam, midi control surface, weather station, train controller.
Plus these more-or-less regular "visitor" devices: DSLR, HD Video camera , USB memory sticks, iPad.
I have 6 USB ports on my early 2008 series mac pro, and it's not enough. So I use a powered hub as well.
I'm not sure how many would be "enough" fast USB ports, given the space limitations of a normal tower case. But it would be way more than six!
Most of my custom control stuff -- lights, security system, salt tank aeration and filtering, antenna rotors, a couple other SDRs, gate locks and opener, sump monitor and AC power monitoring -- are now ethernet, most courtesy of various Raspberry Pi installations. Then there's the commercial stuff: the AV system, the DVR, the game machines, roku and appletv,
Ethernet is better for me, Distance, number of clients, tons of utilities for diagnosis and monitoring, and the speed is decent.
Friend, if you let people get close enough to your hardware to muck with your thunderbolt connector, you didn't have any security anyway.
Restriction of physical access is an absolute first-level requirement for any kind of data / hardware security. Without it, you have nothing. And they have anything they want. There are no exceptions. Absolutely perfect, hardware-based Fingerprint lock? Just open the computer -- with a torch or diamond saw if required -- and walk away with the drives; read and/or decode 'em at your convenience.
Physical access means you have already 100% given up on security; you either trust everyone who has such access 100%, or you must actively restrict them somehow during such access -- guards, monitored cameras, etc.
As I understand it presently, there's no ethernet on USB-C. That's really disappointing. I have applications that require the higher dependability of ethernet as opposed to wifi. And the whole USB to Ethernet dongle thing... that tends to not work so well, at least thus far. There's also the additional security of not being OTA, where anyone in range can intercept your packets.
I'm all for as wireless as possible -- charging, etc. -- but I really don't think it's a good idea to remove the hardwired network connection. Particularly in that ethernet is so well supported across the board.
No, actually, I'm not. This is just my most current effort. I produce quite a bit along these lines, and my experience has been pretty uniform. I mention this last one because it is the most current, and so relates to the extant circumstances best.
Good thing no one is doing that, then, eh? Well, except for the moderators, but hey, it's slashdot, the kids in the basement have to have something fun to do!
That's right. I wrote it because none of the apps in this particular area did what I wanted to do. So I did it myself. I shared the results, and I got some additional value because the users made suggestions that were also useful in the context of my own use of the software. Plus, I'm cheered that others are getting some use out of it.
Of course. But you're missing the point: most people can't afford to dedicate the kind of time I put into that thing; there are bills to pay, and where you might like to be coding GamerGoo for free, turns out the landlord isn't particularly impressed with your zillion "likes" on Facebook.
I only put my experience up there to show that free work is pretty much taken as free work. If you want money, you need to go commercial. That whole "support for money" thing? All that really means is you made bad documentation, or no documentation. Or a configuration file nightmare. I can't see charging people because the docs are poor or the program doesn't work easily and/or well. Really great apps work pretty much right away, and they are either intuitive to use, or are well explained so that they can be made intuitive to use. That takes time; time, for most people, is a net drain on cash reserves or worse, a way to go deeper into debt. I don't recommend the "free" path to anyone who isn't doing it without a concern for making a living from it.
Yes, same here.
I don't care about ego boost, but I do like the idea that my work is assisting someone in some way. For me, the more people I can see using it, the more I'm motivated to work on it.
Perhaps that's it. I don't need the money, and they get pretty much whatever they ask for anyway. :)
Everyone but the people who wrote it, that is.
The problem with winning one's "15 minutes of fame" is that it won't pay the bills.
Which is why this exciting thing called "free", outside of an economy of plenty where it costs nothing to live, or where the author(s) operate(s) under essentially the same conditions, isn't always such a great deal for the author(s).
I have a free [donations accepted, but not nagged for] product out there with about 15k of regular users, and the income from it is as near zero as can be without quite being zero. To date, thirteen people have stirred themselves to donate. The product, however, tends to be used every day or two by those I call "regular users." I know because when it starts, it checks in with my website to see if there is an upgrade [always free], and when it does, I log a "start" to that IP, so I can generate some excellent stats on usage.
There are quite a few competing applications that perform the key functions mine does; but all do it a bit differently, and mine is one of the most feature-rich ones out there. So I have at least some reason to think that the users continue to use it because they find it at least adequate. The feedback I get tends to be quite kind, though that may just be a consequence of not wanting to annoy the author, I suppose. In any case, the considerable work I put in seems to have some value based on all this, and that value has not come back to me in any significant proportion. I can afford it -- don't get me wrong, I was not surprised by this, nor am I inconvenienced -- but that is because I produced pure commercial products for years first.
Depends on if a politician is driving.
You dress up as a really tasty carrot, see, and then...
You may be doing as well on average right now, assuming you're in an area that matches the average in terms of mass generation emissions, but one of the key advantages of an EV is that because it takes its power from the mass generation system after conversion, it is 100% fuel-agnostic. It doesn't know, and it doesn't care. In an area that is generating power from hydro, for instance (as is the case where I live), the regional contribution to CO2 from mass power generation is zero; and in this type of area, you are not doing better, you are doing (far) worse.
In addition, as more non-emission sources (wind, fission, fusion, solar, hydro, tidal, geothermal and so on) come online to replace the emitters, the EV's that were contributing by using mass emissive power transition, without any effort on the owner's part, into zero-present and future emissions vehicles. Your vehicle, however, will continue to emit until the day it cannot run any longer.
So, pollution-wise, EVs are always better.
Has anyone asked Venus about this? Because last I heard, she didn't even like it if you touched her g-string.
How about flags? It's windy as heck here, and putting up a flag is about as easy as anything ever gets. You get a lot of motion, at least in this neck of the woods.
It's not a problem. If they can get rid of the bad gut flora, then they just observe what happens, that's all.
If the person goes back into a state where eating those carbs or volume of food in general does not result in weight gain/maintainance, then the flora were the cause, not the consequence. If the weight stays on / continues to increase, then it wasn't the flora.
The thing to note here is that some metabolisms allow some people, regardless of level of activity, to eat and eat and eat and they don't gain. We know this. So we also know there's some kind of metabolic difference. The thing research is looking for is what that difference is.
If (and it's a big if) those with slower / more efficient metabolisms can be brought into the same metabolic ranges as those without, then there are major health benefits to be had, assuming there are no other side effects, of course.
Up or down. Likely it'll be rotating, because that makes no particular difference to the steering mechanism, it's trivial to see to, and it's a free way to distribute laser energy. Not tumbling.
I'm just assuming there will be a reasonable polish on the surface, good enough to reflect 99% or better of the incoming beam, which leaves about 300 watts applied to the target, which it can't keep steady on, due to atmospherics, target movement (the aforementioned rotation plus vibration unless it's in vacuum) and incidental atmospheric heating / distortion.
Go look at that truck. It wasn't set to reflect much of that energy at all. It also wasn't moving. It also has a decent angle of incidence to the beam. It was also going through 1 mile of atmosphere, rather than 300 to 600 miles of atmosphere, and *that* assumes the target passes directly overhead and you have a *perfect* shot at it. Likely, it won't, and you won't, and the amount of atmosphere will be much greater. 30 kw isn't much in such a scenario. I don't think it'd work.
Oh no, of course not. Not the RV. The rocket airframe, pre-release. If you're going to shoot a laser at a missile, the warhead isn't a reasonable target.
I don't think that's even remotely possible with a 30 kw laser. You'd need a kinetic kill of some kind if you couldn't deliver at least another couple of orders of magnitude with a laser. You want 30 kw well collimated on target after 99% reflection to almost instantly disrupt the reflective surface (ablate it, most likely), which would take about 3 mw. For 30 kw... who would design an RV or a MIRV or a MIRV/RV with such delicate stuff in front or on the surface? Why would there even be a need to? The barometer could be anywhere (so you'd put it in the rear, and inside some heavy protection), likewise the logic package. You *might* manage to disable guidance fins, presuming that's the tech in use, but even so, you still have a live ballistic incoming that's going to go off as designed, albeit perhaps somewhat outside the predicted CEP.
If you're going to actually stop an ICBM from going off, you need to do so before it drops its last stage and reaches its programmed apogee. Things get pretty automatic and pretty unsophisticated once the thing begins the arming sequence, and all the easy-to-blow-up stuff has been left behind.
Compared to the thing actually detonating (we're almost certainly talking multiple megatons here, quite likely double-digit), a core that doesn't even fizzle is no threat at all. Of course, if it does fizzle you're going to get a low yield nuclear explosion on the order of several tens of kilotons (basically it'll act like a small fission weapon instead of a large fusion weapon.) But the odds don't favor enough of the right kind of compression occurring, and anyway, 10-20 kt is highly preferable to 1-40 mt, so you shoot it down if you can.
No shit?
Oh, it definitely is in the case of an ICBM. Anywhere within the atmosphere, the missile will be shaking. A lot. Randomly. Very likely it will be rotating about its long axis as well, in or out of atmosphere, so you'd have to track across the short axis at the rotational speed, then wait for the spot to come around again (while it is also cooling off, if it isn't in a hard vacuum at the time.) The atmosphere between the emission and the target will be turbulent, both naturally and as a result of incidental heating from the beam, and this will serve as an optical lens, moving the beam off target (high speed laser pulses can avoid this with a very fast double pulse: One to blow the atmosphere out of the way, and one to hit the target through the hole. However, 30 kw isn't enough for that, not even close.) Beam collimation is also very important, and the atmosphere fouls that up as well. The larger the area the beam covers when it hits, the lower the energy per square inch is, and the less local heating occurs (or conversely, the more local heat dissipation can be effective.) So you can't fix this by making the spot bigger (decreasing collimation.)
All these factors work together to interfere with the delivery of energy to one well defined region on the skin.
I suspect that in these cases, a kinetic kill is far easier and more reliable. Blow off a cloud of lead pellets in front of the missile, let it run into them, it's finished. Such an intercept missile can self-guide and actively measure distance to target which can significantly reduce misses, and it can compensate somewhat for its own velocity forward by shooting the cloud backwards so it stays in front of the incoming missile longer. Using a cloud of pellets reduces the need to be spot-on. At ICBM speeds, just one pellet is likely to incur completely fatal damage to the incoming missile's airframe. If you significantly disrupt the airframe's streamlining, it will self-destruct due to structural overload. And at these speeds, "significant" doesn't amount to very much.
The surface of the craft can be a mirror.
No useful cooling? At hundreds of miles per hour of atmospheric passage? Hmmm. Not sure I can buy that. A few fins collinear with the forward-back axis of the craft and you'd have quite a bit of cooling.
You are making a LOT of assumptions. All of these matter: Ability of the mirror to dissipate energy prior to ablation or meaningful distortion. Collimation of the beam. Reflectivity of the mirror at the laser frequency. Ability of the laser to stay on target, and for how long. Distance from the laser. Atmospheric clarity and particulate density. Atmospheric turbulence. Disruption from atmospheric heating.
It's just not as simple as you paint it.
CIWS targeting is, as the acronym hints, "close in." You should think of the distance between the shooter (of anything) and the target as a lever. A tiny pivot at one end of the lever (the weapon's aim) translates to a "much" larger motion at the end of the lever (the point of impact.) Tolerances that will work at 100 yards aren't anywhere near close enough to work at many miles, or hundreds of miles in the case of missiles not aimed particularly at you (so you can be sure they will get close enough to hit.)
There are other issues. That truck was relatively close, between 1 and 2 miles ("more than a mile away"). To hit an ICBM at apogee, even it it goes right over you, you are going to have to spend a lot of energy on atmospheric heating, and you'll lose even more to atmospheric distortion. We're talking 300 to 700 times the distance, depending on exactly what "more than a mile away" actually means. But it is certain that 30 kw at the source will not equate to 30 kw at the target at those distances. So now the problem becomes more than "hit the target", it is also "stay on target for X time", and that assumes that enough energy can be delivered to overcome the missile skin's ability to dissipate it. Because if you can't do all those things, you can't hurt the missile.
Also, the odds of it going right over you kind of suck.
I"m pretty sure a regular mirror would not be employed.
But here's some hand-wavy math.
If a mirror reflects 99% of the light that hits it at the laser frequency (remember, there's only one frequency to be covered), and the light that hits it can heat proportional to 30 kw (however one figures that), then the mirror is absorbing a 300 watt equivalent and reflecting the rest unless the reflective surface fails.
If the reflective surface is highly heat conductive and the beam isn't all that tightly collimated, likely it won't flinch at all. Like any impact, the effect is all about how much energy you can shoehorn into the smallest possible area. If the beam is ~1/3 of an inch on target, then given 99% reflectivity, it's effectively 1 kw / square inch. If the beam is 1/30th of a square inch on target, it's 30 kw/square inch absorption after reflection. So it makes quite a difference. I think.
Anyone who works with lasers and mirrors, feel free to step in and correct or expand.
Pretty sure if you "see the red dot a mile off", the location where your eye was is just the steaming, goo-surrounded beginning of a well-cauterized hole that completely transits your head. Assuming tight collimation. With a broader 30 kw beam, your head would explode (steam pressure), and with a really broad beam, you'd turn into a human crisp before you had time to think "Hey! Las..."
Congress comes to mind.