shynung

Seconded. ED should at least be tinkering with microwave-beam R/C planes right now.

http://forum.kerbalspaceprogram.com/threads/23979?p=1608640&viewfull=1#post1608640

Governments around the world are already doing that, by subsidizing cleaner energy sources and (sometimes) putting heavier taxes on less-cleaner sources. But at this level, they can only do so much. The initial investment required for clean energy production is still quite steep for most people to afford installing the equipment in the first place, even in large-community scales. Otherwise, solar power plants and wind turbines would outnumber coal power plants already; I'm not seeing that as of yet.

It does, but in a different way. Wind turbines cost more in equipment, but the operating costs are reduced to maintenance alone. Fossil fuel-power steam turbines have to deal with all that, plus the cost of fuel being shoved in. On the other hand, wind turbine construction and components are much trickier than a steam turbine's. Along with the gearbox, the generator, huge blade assemblies, and the tower must be built on a suitable (windy) area, which is typically not very easy to reach compared to the industrial areas (or practically anywhere) steam turbines are commonly built on. Steam turbines also don't need a gearbox - they're directly coupled to the generator - which makes them somewhat simpler in construction than typical wind turbines. They do need a boiler, though; that's the thing that sucks up operational funds the most.

Not exactly true. Windmills use planetary step-up gearboxes, which occasionally break down. If not running, the gearboxes would last longer from reduced wear.

Theoretically, yes. Practically, that's another story.

Note: 'economic professionals'. They're generally not good engineers. If people like Nibb (or pretty much any realistic engineers) were in their team, they'll either scrap the idea outright (and come up with a new one), or make more modest estimations. SpaceX, in this case, started out modest. They learn to build small rockets first (Falcon 1), make a VTVL rocket-like vehicle to learn how to land them safely (Grasshopper), then they build larger rockets (Falcon 9), along with a capsule to go on top (Dragon). Right now they are applying their lessons from Grasshopper to learn how to land Falcon 9s safely. After that's done, then they'll reach other milestones that they plan (Falcon Heavy, Mars Colonial Transporter, Dragon V2). That's why NASA trusts them; they are able to, and have proven their capabilities enough for NASA to inject them some funds. Skylon, though? It's almost an all-or-nothing affair. Either the final product will work or it won't. Their technology requirements are quite tall (the precooler system alone gave them a lot of trouble already), and their cost estimations have no real grounding. They don't even build small-scale versions of the thing, let alone actually flying it. Almost all of the dev funds go to the engine, which while quite logical given that the fancy motor is the lifeline of the craft, almost everything else is relatively undeveloped. SpaceX builds its might by making small steps. Skylon tries to make giant leaps all at once. Which of the two do you think is more likely to succeed?

Angel, we've discussed this before. http://forum.kerbalspaceprogram.com/threads/84583-Space-economies-and-economics Replace Skylon with FH Reusable. Even the '90% cost reduction' is mentioned here again.

A cost reduction of 1% is hardly significant.

Payload Assist Modules, which are generally Star-series small solid rockets, are occasionally used as upper stages already.

There isn't any economical incentives to go to Mars right now, aside from simple curiosity. Even then, the vast majority of them came from space agencies whose scientists are trying to study Mars up close.

Unlike communication satellites in GEO, the planet Mars currently has no economical value. If a private company like SpaceX goes there, it's because a national space agency (who is usually the first to explore new places) was fed up by its own launch vehicles and decided to buy them from SpaceX. That's a bit of a stretch, if you ask me.

Again, you've missed the point. It is easy to understand how his 'truth' would stand under our scrutiny, because we've seen what he has not. Assuming a lack of communication, he'll never know the real 'truth', and have to live with what he knows for the rest of his life. Right now, we're in his position. We've seen the universe around us contain everything, and we see no obvious 'windows' or 'doors' to to it. We cannot observe or travel to the 'outside' of the universe, at least not now. We are the man who is locked in the house. How is it not logical for one of us to conclude that there are no other universes besides our own? You may argue that this may not be true. And you may point out that someone better informed in the future could make a better conclusion than what we have. But for now, we have no evidence about the existence of the 'outside' of the universe. While absence of evidence may not mean evidence of absence, in this case, the existence (or lack thereof) of another universe have little visible effect on the workings and mechanisms of our universe, at least as far as one can predict from here, so it is convenient to simplify the hypothesis by stating that there are no other universes out there.

I was thinking of the species whose existence we are supporting directly (like cattle), but I think you have a good point.

Or becoming too slippery. Nobody adopted roaches, but they go on living anyway.

It matters not whether he is wrong. What matters is that he'll never know for sure whether his hypotheses about the 'outside world' is correct, since he has no way of confirming it. It's easy for us to falsify his assumptions due to our experiences concerning the 'outside world', but what about him?

Not sure if that'll work for tigers. They don't reproduce quickly, for one. Also, it doesn't have to be food. Dogs aren't usually eaten by humans, but they evolved along with us anyway. Good point. Humans aren't the only ones to have taken advantage of another species (by farming them), but they are also being taken advantage by rats, mice, roaches, and others living alongside them.

One could make that sort of assumption if he never looked out the window. Or if the house had no windows at all. From his perspective, there's no reason to believe that there exists other places, or what they looked like.

So the best trait for animals living in this age is to be useful to humans, then?

That's one reason LH2/LOX engines generally run rich. The other reason is that the extra hydrogen acts as coolant, reducing the combustion temperature, prolonging engine service life.

It was an old term, way before KSP was conceived.

That's about it. Though, regular people never really underestimate chemical rockets, even solid ones. They're mighty beasts, to say the least. I think SpaceX is going the right way. Their Falcon 9 rocket uses almost identical engines in both the lower and upper stages, so that all of the engines can be made in the same factory. Even more, a single rocket uses 10 engines (9 on the lower stage, 1 modified on the upper), so they reap the benefits of mass-production even with low launch rates.

Yeah, that was used in the SSME/RS-25 engines.

I struggle to understand how would one attempt to land on an airless body using a giant magrail. It's like trying to shoot a bullet at another gun and having said bullet fly into the barrel of said gun through the muzzle.

Not much development can be done with liquid rocket engines, other than materials and manufacturing advances. The technology itself is already mature by the 70's, and not much progress in terms of design changes has took place since then. Any further advances would have to be gotten from using more energetic propellants or nuclear thermal rockets. And by energetic propellants I mean things like chlorine trifluoride, or the like. Super-reactive stuff, basically.