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Comment Re:Skylon? Seriously? (Score 1) 64

Simple, reliable, easy to build, but not really optimum at all for a first stage. Much better for high impulse orbital transfer. Yes, nuclear electric might be more efficient, but its unlikely you're going to build a really high thrust nuclear electric design, and for lower impulse designs why not make it solar? The real advantage here though is the ease of development and deployment, you get quite a lot of bang for few bucks. The basic design of a Nerva-class system is already in the bag, it could be flying in 3-5 years if there was some impetus, and its well within the level of budget that could be realistically associated with a commercial venture.

As for not giving the exhaust velocity desired for missions to the outer solar system, there are a whole class of missions, to the inner solar system and asteroids, that would be quite feasible even using fairly primitive nuclear thermal systems. More advanced systems could be pretty interesting as well, though something of the nature of an Orion/Longshot type nuclear impulse rocket would probably make the most sense for really large manned deep space missions. We're likely at least a century away from mounting those however, so its not exactly something that relates to SPS.

Comment Re:If it is 1/3 the power of the sun... (Score 1) 64

Well... That's not ENTIRELY true, you'd need a Rectenna of about 1000m in diameter, for reasonably high efficiency, but it could be considerably smaller in many cases and still be valuable, nor is that size necessarily prohibitive. This is all assuming only GEO, the divergence for lower orbits is MUCH less, so it becomes a balancing act between costs and limitations on the ground vs potentially needing more satellites and/or taking some time to reorient the ones you have.

Its not a perfect system by any means, but it could be hugely valuable in many situations. How many billions would it have saved the US in Afghanistan? What is the additional operational flexibility worth? Its hard to even put exact numbers on it.

Comment Re:Skylon? Seriously? (Score 1) 64

Trump is amusing, at least for some values of amusing.

The question is, then, even if you had this microwave powered electric tug, will it really be affordable? I mean its going to cost what, $10 billion to get that going? At least that much, and that'll get you what, one? So, maybe you gotta go slower and accept the hits. Don't deploy your SPS until it gets to GEO. There are creative answers.

Comment Re:Skylon? Seriously? (Score 1) 64

Lets assume Skylon works, that doesn't solve your problems. At current sorts of launch scales a hypothetical SSTO launch vehicle might be cheaper to operate than say SpaceX's launchers, but that doesn't mean launch services will be that much cheaper. Their costs are related to supply and demand, and with the initial system probably limited to a fairly small throw weight and requiring a conventional upper stage for GEO chances are slim that an SPS will make economic sense (IE GEO costs will still be far above your $200/kg level). Its unclear there's a continuous set of demands starting at that level which ramp up capacity to the levels where $200/kg GEO actually becomes feasible.

In other words it could be many decades, way out in the later part of the 21st Century before that happens, because you could well be waiting for other space industry applications to take off, but they're all caught in the same chicken-and-egg trap. In the past governments built things like intercontinental railroads, large canals, ports, etc, but building out a cheap space launch capacity is a LOT more expensive. While I'm a 'fan' of the concept, I remain skeptical that this is something that will ever happen.

Comment Re:If it is 1/3 the power of the sun... (Score 1) 64

Why focus on commercial baseload power? The cost to the military or other organizations to provide power in remote hostile locations is orders of magnitude higher than $0.03/Kwh. Isn't your best bet to fill that demand? Competing with coal seems a fool's errand when you can compete with diesel fuel humped over 3000km in tankers, forwarded to advanced basis in Afghanistan on Humvees, and burned in inefficient generators. The costs there are more like on the order of $30/Kwh. Building a reception grid for 10Kw of power out in nowhere is pretty straightforward, the materials are dirt cheap and construction is simple, probably just something you can air drop and set up in a few hours.

This is your initial market. Yes, utilization will be maybe 80% lower than with baseload power, but you can charge 100x more and still undercut the alternative without even breaking a sweat. My guess is, worldwide there's a pretty significant demand for such power. Once you've got say 2-3 medium sized satellites up there filling this demand then you've got a toehold in space and you can incrementally ratchet down prices, filling more and more of these various niches at lower price points. The jump to baseload power will then be vastly easier.

Comment Re:Can GIMP not read PSD? (Score 1) 233

I really don't know, but this was WAY back, I don't even think in those days WineLib was a viable option. We were one of the first web development shops in existence, back in '94. We got access to everything, all sorts of weird "this does not exist" software. Amigas, DEC Alpha based NT4 workstations, tons and tons of stuff that nobody in the current generation knows squat about.

Comment Re:Can GIMP not read PSD? (Score 1) 233

It was actually a SCO binary and you had to have the SCO binary compatibility patch, which hasn't worked in years (since like kernel 1.2.x or something). I still know a guy that works in a shop that has a linux box (I think its a VM now) running some ancient RedHat just so they can support a specific workflow and print WP documents. That whole tech stack got deeply embedded in the legal field way back and they're STILL not entirely free of it.

Comment Re:Can GIMP not read PSD? (Score 3, Interesting) 233

Adobe WROTE photoshop for Linux YEARS ago, we actually used to run it, but it was a limited release application that was only provided to specific customers and beta test sites. There's just never quite been a critical mass to make it profitable to release stuff like that. Porting, if your a sophisticated shop that already supports several platforms is really pretty trivial.

Comment Re:Oh the pain... (Score 1) 166

Hahaha, that wasn't IDX (AKA GE Healthcare) was it? I interviewed with them back in the early 90's. They were the most arrogant dorks you can possibly imagine, and their product frankly stank. They had a very good grasp of the business side of things, but their actual software engineering practice was execrable and MUMPS couldn't have helped.

Comment Re:leaving aside the potential for abuse... (Score 1) 87

Well, maybe we shouldn't allow fire trucks to race down our streets with their sirens blaring! Clearly there are pros and cons to different things, but how often do you actually get bothered by a fire truck? What is any more creepy about a drone flying by than a police cruiser sailing down your street? I think its pretty clear the intent here isn't to carry out constant areal surveillance.

Comment Might make sense (Score 2, Interesting) 87

I mean its kinda hard to say if the economics really do make sense or not, but its at least plausible. And frankly, if the location and purpose of use for each drone is available in near-real-time, then its hardly a spying tool, though it could still be used for surveillance in some sense. That would seem to address the bulk of the privacy issues, and its difficult to be too sympathetic with most of the other ones.

Wherever you go...There you are. - Buckaroo Banzai