Well, no, not at all. But I do happen to have an undergraduate degree in physics, so I know enough to tell when he's got something obviously wrong in that department.
Oh, and there's multidisciplinarian John 'Rocket Scientist' Shilling being cited yet again, this time as an authority on nutrition. Notice that the author makes damn sure you know he's getting the opinion of a 'Dr.' on this one - Hi, John!
A. Dr. Schilling also has a Bachelors' degree in Physics, as I recall.
B. I've known John since around 1990 and you, sir, are on these points acting like an ass, repeatedly, whether John is right on specific facts or not. You have repeatedly gone beyond naming him as a direct or indirect source and questioning source details (without your own detailed analysis presented as counterargument, I should add). You've personally insulted him at least three times in thread, when he and his work and his character were not the focus of any of the discussion.
Please knock it off.
]]>Err, I guess Vanzetti is talking about something like this: http://en.wikipedia.org/wiki/Whipple_shield In tank speech, it's somewhat like spaced armour: http://en.wikipedia.org/wiki/Spaced_armour Seems to work with smaller particles, guess it doesn't work that well with bigger ones that don't disintegrate that fast.
Whipple shields work by first disintegrating an object, heating it enough to cause it to vaporize and spread out, and then by using empty space to spread that mass out across a wider area before it encounters the final shield layer.
Roughly, the shield's outer layer sectional density needs to be about the same as the sectional density of the object, or else energy transfer won't efficiently vaporize it. The details depend on velocity and material makeup, and scale length (shockwaves within the object, etc, compared to velocity). But roughly, if sectional density isn't about like the object, it's likely to penetrate.
Consider the difference in sectional density between a small meteorite (1 gram, 1 cm^2) and a KE long rod penetrator from a tank gun (M829A3, 10,000 grams, 3 cm^2).
]]>Yes, I'm talking about Whipple shields and more advanced stuff - like independently flying Whipple shields.
]]>As for more massive satellites, problem is more massive satellites mean more debris in the case of malfunctions; which means a higher danger, which means more massive satellites, which means, well, quite likely a runaway development. Also note more massive satellites might mean bigger particles, which have a longer orbital lifetime.
So, well, limiting things to smaller satellites disintegrating into quite small particles might be another option. call it sustainable satellites...
]]>I can't seen any military establishment accepting that they should regard a robot[1] as dispensable.
[1] Certainly not one that's more than a single-shot "fire-and-forget" missile. And even with the missile they're likely to argue that if you might be going to lose it anyway it would be "better" to have it explode, because then if there is a baddie around you might get them in exchange for the missile.
]]>In Vernor Vinge's "Marooned in Realtime", that was where you kept your life support and extended-brain bits after the Singularity...
]]>Luggage.
]]>I hear all the time about how tech that couldn't function without a satellite in the loop being is being replaced by tech that can, due to some new development or other. In fact, it's been discussed here more than once, cf. using solar-powered planes able to stay aloft for months on end replacing communications satellites.
My question is, just how far could plausible technological advances take you in this direction? Conversely, what applications are by their very nature unable to drop a space-based component? My guess is that there's not much stuff in the latter category, and that mostly because of the constraints of physical law. Iow, even if we're unable to dispense with satellites altogether, at least successive machine generations will trend towards smaller - and therefore cheaper - satellites.
]]>That said, there are a bunch of things that are easier with space: GPS (can be replaced by inertial navigation or cellular networks, so long as there's not a disaster), intercontinental communications (can be partially replaced with undersea cables), and weather satellites (pretty necessary for global transportation--I suppose a metric buttload of highly advanced drones could fly into all the clouds and more or less figure out what they will do next, weathersats do have a better vantage point, and make the logistics of oceanic shipping much easier.
]]>Everybody has probably experienced the weird stop-go effect on overcrowded major roads, like a pressure wave propagating down the traffic lane. A co-ordinated train of self drive vehicles could avoid that, just rolling along at the speed limit. Accidents could be met with co-ordinated lane merging to filter round the blockage while allowing rapid access to emergency vehicles.
Of course, this is predicated on banning manually directed cars, but you no longer see horses and buggies on the autobahns either.
Crazy talk, I know, right up to the point it becomes unavoidable.
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