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#91
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On Fri, 04 Jun 2004 00:45:58 -0500, Pat Flannery wrote:
If they were unguided, they would be considered "rockets" not "missiles" by the standard use of the two terms in regards to them I'm pretty sure that missile is just the general term for a weapon that is thrown or projected. A rock is a missile if it's thrown or projected towards a target using a slingshot or the like. Otherwise the term guided missile would be redundant. The term unguided missile is also in use. |
#92
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Scott Hedrick ) wrote:
: "Henry Spencer" wrote in message : ... : There was even an early-70s proposal to commercially finance a final : Apollo mission, although it didn't get very far, at least partly because : NASA's reaction was total hostility. : Which it would still be, but they'd do it, because now they wouldn't get : funds any other way. : Why aren't we selling advertising on our birds? So, you want the government to be in the business of business? Damn commie! Eric |
#93
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![]() "Christopher M. Jones" wrote in message ... Pat Flannery wrote: Christopher M. Jones wrote: The missiles Henry is talking about simply went up and down. The reason they needed advanced flight control systems was to get close enough to the target so that a megaton nuke would actually do some damage to it. That tells you the level of accuracy and sophistication we're dealing with here. Here are some of the Circular Error Probabilities of the first ICBM's: (A lot of snipping) Atlas- 2 nautical miles. Back in the early days of Atlas missile full range testing with active radio guidance when everything worked the warhead was falling into a .5 nautical mile circle most of the time and within .25 nm quite often. If things went seriously wrong the warhead ended up nowhere near the target. Command guidance was regarded as undesirable because of vulnerability to enemy countermeasures so there was a shift to interial guidance systems. The figures I saw on this were 5-10 nm. Quite close enough for soft targets such as cities. Not good enough for taking out launchers in silos. This is circa 1960and inertial guidance systems became much more accurate later. One of the biggest advances in target accuracy was achieving more accurate mapping. If you don't know where you really are at the launch point and don't know exactly where the target is then accuracy is just a bit hard to achieve. I bet Henry Spencer could give us a real lecture on this. Mike Walsh |
#94
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![]() Rick DeNatale wrote: I'm pretty sure that missile is just the general term for a weapon that is thrown or projected. A rock is a missile if it's thrown or projected towards a target using a slingshot or the like. In the original definition of the word, yes...rocks and arrows were called missiles. In the present aerospace usage fin-stabilized unguided rockets aren't called "missiles"; otherwise Mighty Mouse and Hydra rockets would be Mighty Mouse and Hydra missiles...as would Bazooka rounds; although if an unguided rocket gets big enough, or has an atomic warhead, then people start calling it a missile (i.e. Honest John). Does the "missile" designation apply to unguided surface-to-surface rockets only, as opposed to air-to-air or air-to-surface unguided rockets? Otherwise the term guided missile would be redundant. The term unguided missile is also in use. Not very often, and usually in reference to a guided one that isn't working right, or something with an atomic warhead on it, like the above-mentioned Honest John. Guided missiles usually have an ability to home on their target after launch, either via internal homing apparatus (Sidewinder) or with external aid (Sparrow) or via external commands to the missile (TOW). I think the whole thing is in a state of flux between dictionary and common usage; rather like the whole "shrapnel" mess in which the term shrapnel is used in regards to fragments from an explosive's casing, as opposed to a specific type of air-bursting shell designed to project spherical sub-projectiles. Then of course there are the gun and the rifle; and the clip and the magazine. Pat |
#95
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In article ,
Mike Walsh wrote: Command guidance was regarded as undesirable because of vulnerability to enemy countermeasures... Also because the launch site needed an elaborate set of radars which were virtually impossible to harden against attack in any meaningful way, and could be used for only one launch at a time. Almost any credible scenario for *using* the things required either rapid-fire multiple launch or the ability to ride out attacks, so command guidance just did not make much sense for large-scale deployment. One of the biggest advances in target accuracy was achieving more accurate mapping. If you don't know where you really are at the launch point and don't know exactly where the target is... In particular, apparently there was some unhappiness when people realized that the relative locations of the *continents* were not known accurately enough for ICBM targeting. Within a continent it was possible to do quite accurate surveying with aerial photos and the like, but accurately determining the precise distance between North America and Eurasia was not so simple, and some effort had to be made in a hurry. -- "Think outside the box -- the box isn't our friend." | Henry Spencer -- George Herbert | |
#97
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"Terry Goodrich" wrote in message . ..
Hi All, I was just wondering, we have a 10~20 gram stone worth 5 million. Surely someone could design a robot to go to the moon and pick up 20 kilo of rock (pebbles, dirt, etc. it probably wouldn't matter). Assuming that the value of the rocks would decrease in value as much as 90% due to the fact that they would be on the open market, 20 kilo of rocks could be worth as much as 500 million dollars. One should be able to build and launch a probe for that much. Terry Moonstone feldspars weigh about 3g per cc and could probably be cut as thin as ten microns, about 30 sections per cc with waste dust. Thats about a million gemstone sized sellables, out of your 20 kilo of rock. If documented with optical and electron microscopes and sold with a CD that tells the story of its collection and selenological science, they might go for a thousand dollars a shot, for the first batch. A billion dollar haul that with the internet, could be certified the real McCoy, by any jeweler. A small sample vaporized by a laser and analized by a mass spectrometer, could reveal an age of over four billion years, if you pick the right rocks. Lead in Uranium oxide crystals that is turned into something a hundred times more valuable than gold. If there were just some way to get that kind of money at the front end of the enterprise.... Stephen Kearney |
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