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http://www.spacefuture.com/arc...

There is your product, or at least the source of the product. Next you do orbital manufacturing, and start building. Build what you say?

https://en.wikipedia.org/wiki/...
or even spacecraft, tugs, mining vessels, trading vessels

There are places to go as well, we could start moving out into this solar system, and begin the process of building interstellar spacecraft. Generation ships are the way to go to get to other stars, while we continue to work on the possibilities of superluminal travel ( https://en.wikipedia.org/wiki/... ). But of course, it is people who look to the future who build the technologies of the future, not those who constantly doubt, such as those who doubted we would ever reach space ( https://en.wikipedia.org/wiki/... ).

The SSME has (barely) enough performance to do it.

You could easily conceive something with even better performance than the SSME with chemical engines e.g. LOX/Slush LH2, TAN nozzle, etc.

This is a good analysis of NASA. It's a good oldie, but it should be read more often.

I thought launches were supposed to be made as close to the equator as possible

technically you're right...

http://www.aerospaceweb.org/question/spacecraft/q0080.shtml

but i'm also pretty sure that politics, economics and bureaucratic red tape are just as significant in selection of a launch site. there was talk years ago about private launches from Australia, which a lot of people claimed was because of ideal launch conditions, but was actually because it was cheaper for the launch company. insurance is one of the largest costs in launching equipment into space. the united states government makes it very difficult and expensive for companies to even get approval to launch (even harder since 9/11). VA is within the USA so i can't give you a definite answer to your question, but i wouldn't mind betting that politics played a role.

the united states government doesn't want private enterprise to succeed in space because if they make it easy it will promote development of much more cost effective launch systems which will then open the floodgates... ultimately the US military loses the high ground it's held over everyone (except maybe russia) for the past half century

this will probably be waived off as conspiracy (and it is for the most part) but i believe that NASA's private launch initiatives are a ruse... i wouldn't be surprised if there are a few "accidental" launch failures to derail private launches in order to secure more funding for launches by NASA and USAF and slow down private space industry in general, especially as nasa and military budgets become more constrained in future.

http://www.spacefuture.com/archive/the_prospects_for_passenger_space_travel.shtml
http://www.spacefuture.com/archive/space_policy_space_tourism_and_economic_policy.shtml
http://www.spacefuture.com/lists/sf-discuss/December-1999/msg00002.html

I thought launches were supposed to be made as close to the equator as possible

technically you're right...

http://www.aerospaceweb.org/question/spacecraft/q0080.shtml

but i'm also pretty sure that politics, economics and bureaucratic red tape are just as significant in selection of a launch site. there was talk years ago about private launches from Australia, which a lot of people claimed was because of ideal launch conditions, but was actually because it was cheaper for the launch company. insurance is one of the largest costs in launching equipment into space. the united states government makes it very difficult and expensive for companies to even get approval to launch (even harder since 9/11). VA is within the USA so i can't give you a definite answer to your question, but i wouldn't mind betting that politics played a role.

the united states government doesn't want private enterprise to succeed in space because if they make it easy it will promote development of much more cost effective launch systems which will then open the floodgates... ultimately the US military loses the high ground it's held over everyone (except maybe russia) for the past half century

this will probably be waived off as conspiracy (and it is for the most part) but i believe that NASA's private launch initiatives are a ruse... i wouldn't be surprised if there are a few "accidental" launch failures to derail private launches in order to secure more funding for launches by NASA and USAF and slow down private space industry in general, especially as nasa and military budgets become more constrained in future.

http://www.spacefuture.com/archive/the_prospects_for_passenger_space_travel.shtml
http://www.spacefuture.com/archive/space_policy_space_tourism_and_economic_policy.shtml
http://www.spacefuture.com/lists/sf-discuss/December-1999/msg00002.html

I thought launches were supposed to be made as close to the equator as possible

technically you're right...

http://www.aerospaceweb.org/question/spacecraft/q0080.shtml

but i'm also pretty sure that politics, economics and bureaucratic red tape are just as significant in selection of a launch site. there was talk years ago about private launches from Australia, which a lot of people claimed was because of ideal launch conditions, but was actually because it was cheaper for the launch company. insurance is one of the largest costs in launching equipment into space. the united states government makes it very difficult and expensive for companies to even get approval to launch (even harder since 9/11). VA is within the USA so i can't give you a definite answer to your question, but i wouldn't mind betting that politics played a role.

the united states government doesn't want private enterprise to succeed in space because if they make it easy it will promote development of much more cost effective launch systems which will then open the floodgates... ultimately the US military loses the high ground it's held over everyone (except maybe russia) for the past half century

this will probably be waived off as conspiracy (and it is for the most part) but i believe that NASA's private launch initiatives are a ruse... i wouldn't be surprised if there are a few "accidental" launch failures to derail private launches in order to secure more funding for launches by NASA and USAF and slow down private space industry in general, especially as nasa and military budgets become more constrained in future.

http://www.spacefuture.com/archive/the_prospects_for_passenger_space_travel.shtml
http://www.spacefuture.com/archive/space_policy_space_tourism_and_economic_policy.shtml
http://www.spacefuture.com/lists/sf-discuss/December-1999/msg00002.html

In this Astrophysicists professional opinion it is unlikely (and probably impossible) to construct a rigid "shell" structure which is able to hold itself over the sun, or even hold itself apart from it's own gravity field before collapsing into rubble (as another poster stated). If you did construct such a structure it would also be unstable and prone to falling into the sun, ala Ringworld, but if you could construct such a structure in the first place that may not be an issue.

The simple fact is that the stiffness/density ratio to withstand the gravity of a sun is enormous, probably impossibly so. Also, that sort of structure would probably have an enormous mass.

A very popular way of solving this is the "Dyson Swarm", which other posters have mentioned. Just keep building and launching normal satellites until they literally block the sun. An alternative (one which is not mutually exclusive to the swarm approach) is to build a structure that does not need to withstand gravity. Instead of a shell build a thin membrane that surrounds the sun, light enough that the solar radiation pressure that object feels is slightly larger than the gravitational pressure. Instead of tending to fall into the sun the entire balloon would inflate out from the sun until it was taut. The structure would then only have to withstand the tensile force of the excess solar radiation pressure, so lets say 1% of the gravitational force, and tensile force can be withstood with lighter materials than compressive force to boot.

So what would the areal density of such a membrane have to be?:

Pressure * MembraneArea = MembraneMass * Gravity

MembraneMass/MembraneArea = ArealDensity = Pressure / Gravity

Gravity = SunMass * GravitationalConstant / radius^2

Pressure = FluxDensity / c (assuming that our membrane is perfectly absorptive, also note that we don't need to take into account the pressure of the photons leaving the membrane, as they will be split evenly between the inner and outer surfaces and cancel each other out.)

FluxDensity = SolarLuminosity / MembraneArea (//*The SolarLuminosity is the total power output of the sun.)

MembraneArea = 4 * pi * radius^2

so: ArealDensity = (TotalPowerOutputOfSun / (4 * pi * radius^2) / c) / (SunMass * GravitationalConstant / radius^2)

The radius cancels out! That means that the same membrane (barring heat constraints) can be used anywhere in the solar system!

ArealDensity = (TotalPowerOutputOfSun) / (4 * pi * SunMass * GravitationalConstant * c)

ArealDensity = (3.839E26 Watts (kg*m^2/s^3)) / (4 * pi * 1.9891E30 kg * 6.673E-11 m^3/kg/s^2 * 3E8 m/s)

ArealDensity = 7.67E-4 kg/m^2

So all we need to do is make a very thin structural membrane, line it with incredibly efficient solar cells, as well as efficient transmission to the laser stations studded every few tens of thousands of square kilometers, into a sheet of membrane that masses around 7 grams a square meter! (safety factor, as well as extra to hold up those laser installations) Easy peasy, that's just an order of magnitude less than a sheet of ordinary paper! For an even more relevant example this paper references a current deployed solar array areal density of 80 g per square meter. Coincedentally enough that's actually exactly the areal density of a sheet of paper, so an order of magnitude of improvement is actually what we are trying to achieve.

As far as the total mass of this system, that's ArealDensity * 4 * pi * radius^2. Let's think really grand and build it 10% past Saturn. .0007 * 4 * pi * (1.1 * 1.43E9)^2 = 2.18E16 kg. That's only 3.6E-9 the mass of our planet, or 2.3E-5 the mass of Ceres, so once we get Asteroid mining started up that'll be no problem. Heck, if you wanted to be lame and build it at 1.1 times Earth's maximum distance from the sun you could make it more than 100 times lighter than the Saturn variant.

Plenty of web pages address this. Here's an example:

http://www.spacefuture.com/archive/conceptual_study_of_a_solar_power_satellite_sps_2000.shtml

Space is already economically important. A 1996 KPMG report put the space GDP at over $77 Billion/year-and that is well over $100 Billion/year today. That is bigger that some significant countries.

I would argue that stuff like monitoring pollution, improving communications and what not are in fact improving humanities prospects on the earth. There are various technical directions that might mean independent off-earth settlements of humans, but they sure aren't near term.

The thing is, space is one of the few real engines for economic growth in a world economy that is rather troubled.

Interesting idea especially when combined with a table from one of TFAs. Since I can't link the first table I'll try posting it...

Table 1 Mission Velocity Requirements (delta-v)
Earth surface to LEO 8.0 km/s
Earth surface to escape velocity 11.2 km/s
Earth surface to GEO 11.8 km/s
LEO to escape velocity 3.2 km/s
LEO to Mars or Venus transfer orbit 3.7 km/s
LEO to GEO 3.5 km/s
LEO to HEEO 2.5 km/s
LEO to Moon landing 6.3 km/s
LEO to Near Earth Asteroid approx 5.5 km/s
Lunar surface to LEO (with aerobraking) 2.4 km/s
NEA to Earth transfer orbit approx 1.0 km/s
Phobos / Deimos to LEO 8.0 km/s

So once you get into orbit the inner solar system really does open up to you... Provided you know how to keep people alive in space for long durations. Also, notice the delta-V entries for "Lunar surface to LEO (with aerobraking)" and "NEA to Earth transfer orbit". Solar-powered mass drivers could achieve those numbers for modest sized cargo containers full of raw or semi-processed materials like ore, metals, or ice.

You want Firefly? First you need FireNASA.

http://www.spacefuture.com/vehicles/how_the_west_wasnt_won_nafa.shtml

NASA should be a regulatory agency, just like the FAA. But when you give regulation to a "competitor-in-the-field," amazingly, no-one else meets the regulatory requirements to compete.
(offtopic/ Think of that when they talk about a "public insurance plan" too. \offtopic)

Poor Author C. I wish he had lived to see his 2001 visions come to life. . .

Sometimes the right decision is to listen to the engineers and not the scientists.

Whether scientists or engineers, if they work for NASA it is rarely any point in listening to them. Why? Well, I think this "story" explains it well enough.. The NASA engineers are still playing around with 1970s technology and they think it is as cool as it was in the 1970s when the same engineers built it.

What you're essentially wishing for here is that NASA cease to be, and the USA get out of space travel/exploration.

You seem to be implying that one thing causes the other. To my mind, the reverse is true - as long as we have NASA, we won't get to space travel/exploration.

Whatever happened to the Phoenix? VTOL, SSTO, and a dollar-per-kilo payload to orbit cost a mere fraction of either the shuttle, the Soyuz, or the Orion.

Thats a ridiculous argument. We would never put something a mere 10 meters squared into orbit for this purpose. Read this for some real options: http://www.spacefuture.com/archive/a_fresh_look_at_space_solar_power_new_architectures_concepts_and_technologies.shtml. Also, we are constantly sending the shuttle and other stuff into space anyway, so if its not a solar panel being launched it will be something else using your 100kg of fuel.

Bottom line-> don't spend billions on oil exploration and refineries etc. Just put massive solar cells in space or on moon and get cheap energy forever more.

You know what? When I first read your post I thought you must be a freaking whacko nutjob who needed to be protected from the terrible secret of space.

Then, I did some Googling just to see if there actually was any information on SPS.

Whaaaa? TONS. Oops. I was completely wrong about your post. Thanks for an enlightening comment and please let me apologize for almost chucking you in the virtual loonie bin.

Not really. Decay time due to drag for LEO is fairly short. Debris in orbits below 300 km (where ISS lives) falls in less than 30 days. Debris up by the Hubble can stay up for years, but will fall eventually. Here is a chart of orbital decay vs. altitude.

http://www.spacefuture.com/archive/history_of_the_ phoenix_vtol_ssto_and_recent_developments_in_singl e_stage_launch_systems.shtml

All about the powered, precission landing, and quick turn around, reusable craft.

Actually, there is a view that space tourism is the key to making space flight affordable. Space tourism - unlike satellite launches, or science - can grow to a large number of launches per year. Therefore economies of scale can come in to play. According to this article http://www.spacefuture.com/archive/public_choice_e conomics_and_space_policy_realising_space_tourism. shtml space tourism is the key to economically viable space travel. Low cost to orbit made possible by space tourism then opens up the really interesting space opportunities.

Perhaps you should tell NASA, NASDA, and all the thousands of engineers and scientists who have worked on this concept for decades, because every study I've read (some of which are linked to at the bottom of that article) disagrees with you.

  Sure, there are engineering hurdles. But they don't make the concept impossible.

  I'm not going to take the time to rebut all your points - they are already dealt with elsewhere. (This is a pretty good place to start.)

SB

Many people have accused NASA of major stagnation, so that might not be the best example to support your case. As a good example, see How the West wasn't won.

That being said, it seems pretty obvious that within the last 250-odd years, the Islamic world has generated very little in the way of innovation, while Westerners have created a world of technology that's completely transformed people's lives. In fact, others have pointed out that in the 600-odd years Islam has existed, the Islamic world has produced very little compared to the innovative west. It seems like there is a fairly precise correlation between when Islam started growing and when innovation slowed to a stop.

This is not really surprising considering that Islam itself says that the Prophet Mohammed has said everything that needs to be said. It's a bit tough to innovate when you're told everything has already been discovered!

D

And we havent even figured out how to get enough energy into a single stage ship to get to orbit.

Yes we have. Remember the Roton project?

http://www.spacefuture.com/archive/the_roton_conce pt_and_its_unique_operations.shtml

Scary part is that they are actually constructing this "Glass Elevator". I've heard about this from both Slashdot and my Hotel and Restaurant Admin professor. In addition to the space elevator, plans are already being developed for these space hotels in which we will one day be able to visit and view our earth from a completely new perspective. My prof and I have had a few e-mail conversations concerning space tourism. The following is an earlier e-mail that he send to me: Japan and the U.S. already have hotel prototypes as well as flying machines that will fly from here to Australia in 20 minutes. I am a member of the space tourism society http://www.spacetourismsociety.org/ . If interested please visit this site: http://www.spacefuture.com/home.shtml . I am a futurist and totally believe that soon we may spend a weekend in space for less than flying 10 hours to France.

Looks like NAFA's at it again.

Mine WHAT? The economics and physics of the situation are such that Martian material is valuable for using on Mars or in Mars orbit. That's IT.

Actually, it's very easy to get to LEO from Mars orbit. See here. Easier than getting to the Moon, in fact.

Mars does seem a little silly. Asteroids have much higher mineral wealth, especially some rarer minerals. Though the problem is that the world economy has kindof evolved to not need them - flooding the world with them will just collapse that economy, not bring you unlimited wealth.

Centripetal-force-generated artificial gravity systems, like those envitioned by Arthur C. Clarke shown in the film 2001, have been studied by NASA and the Air Force for decades. Basically, it would require a structure of a few hundred meters radius rotating at a few rpm. The scale of such a habitat would be enormous, and the cost associated has not been shown to be warranted as of yet. However, the commercialization of space will probably bring about such an innovation out of necessity (for comfort).
Links here, here, and here.

The big block engine may be too heavy. You have to look at tables of "Thrust to Payload" ratios to get a good idea of efficiency. http://www.spacefuture.com/archive/a_single_stage_ to_orbit_thought_experiment.shtml

The idea of the Shuttle is to work as a service module and to allow astronauts to exit and re-enter the vehicle. Rockets are still used to launch satellites--but they can't be used for space stations and repair missions. Or at least, you would have to add a lot more of a return payload to the lifting body and add other complicated devices that would have to be thrown away. So the thought is, by the time you fix a rocket to do this type of work, you are better of with some kind of shuttle (not necessarily the one we have).

There is also the Delta-V to consider. Weight of propellant is not the only issue--its Volume to Mass ratio also has an effect, giving denser fuel an advantage. http://yarchive.net/space/rocket/fuels/hydrogen_de ltav.html

Anyway, the ideal engine would be an Atomic engine for real power. But say "Nuclear" to anyone and rationality goes out the window. http://www.nas.nasa.gov/About/Education/SpaceSettl ement/75SummerStudy/4appendM.html But it is quite feasible to create a safe and effective nuclear rocket.

That's funny. Douglas Aircraft Co thought it was feasible in the 60's. Gary Hudson has been working on SSTO since the 70's, and cites several efforts by other companies. Even NASA bought off on the idea when it started the X-33 program. They just botched it by picking a vaporware design that involved all sorts of innovations above and beyond SSTO. So why exactly are you claiming that SSTO "isn't feasible (yet)"?

Burt Rutan aside, I wonder what NASA would have done with that money had it not to worry about keeping contactors happy.. Granted the X-33 turned into a fiasco, but maybe had they concentrated on a manned version things may have worked out better.

The truth is the shuttle is coming to the end of the line. While it is a great piece of engineering, parts are no longer being manufactured and it is costing a fortune to keep it running. I wouldn't kill it for either of the previous reasons until a reasonable replacement is found. The catch is that there is no reasonable replacement and that the shuttle is likey to be grounded full time in 10 years with no replacement - this is a big problem. It is starting to sounds like the Concorde.

The oxygen will last for 5 months, but what about the booze?

I imagine the morale of those aboard the station, and of those tapped to rotate onto the station is pretty low. The actual space station is a half assed effort at space colonization, and a money pit nobody wants. It was concieved in the Reagan era and in a spirit of Glasnost (or whatever the buzz word was at the time) as some kind of international gesture or that would herald in a great age of space exporation, or at least international cooperation. But there was no real goal or purpose in building it other than building it, and all the countries that began work lost interest in finishing it, but no one wants to be responsible for killing it off entirely. (I'm too lazy to look up references, but there are modules that were never completed, and perhaps were never even started)

The loss of the use of NASA's shuttle was the biggest blow, since resupply by soyuz is barely adequate for the current crew, and there is no hope of actually putting a working crew up there without it. Expect the station to be abandoned by the time the shuttle is finally retired, that is, if the shuttle ever flies again.

I suspect that the only way to get a permanent presence off planet is through private efforts--i.e. companies that hope to make a profit from space. If I weren't destined to die a virgin, I would like to honeymoon there.

People who talk about space programmes (at least at Slashdot) seem to fall into two sets of camps.

1) Send rockets into space with a space capsule (reusable or not, we really don't care).

2) Use a reusable space plane.

Now the people in the first camp will argue about efficiency, and cost, and reliability. They've got a million reasons, much like those that advocate only sending robotic space probes into space, and forget manned space flight.

Because I don't agree with them, and also to bring a smile to my face, I like to believe they like this idea because rockets resemble a big penis (something they may be lacking themselves), and that the "capsule" at the end is like the ejaculation of sperm into space. But again this is just my personal opinion.

What the people in the first camp DO lack is efficiency of the imagination. Thats for sure. They see a short term solution which forestalls a long term one.

The people in the second group, are more visionairy, and understand that in order to make space really accessible and interesting to humanity, you need something thats more like a space plane. Something that does not need to be manufactured for each flight and transported to a certain location (rocket). Something that can be turned around maintenance wise within 24-48 hours, and is preferably SSTO. Its no coincidence that Scaled Composites space ship that won the X-Prize was a space plane. And its no coincidence that Richard Branson signed up with Scaled Composits right away to start Virgin Galactic -- a service to take people up into outer space for around $250,000 a flight. It matches all of these qualifications, and more than just some metallic cylendar sitting on a launch pad, it captures the imagination.

Also with a rocket you lack the pushing of technology forward. Building something that does SSTO and goes from Tokyo to New York in an hour, will require serious advances. And these advances could have (and probably would have) a huge impact in other areas. With a rocket, you just use refined 50s and 60s technology. In fact, if you consider that most rocket designs are still based on the V2, this would in fact be 40s technology. Sure reliable and cheap. Save it for Arianne Space. But for NASA, who's initial setup was to push the envelope as it were in space and space related technologies, its a bit disappointing to take a BACKWARDS step.

Anyways here's a neat little page that talks about past and future launch vehciles. Notice that there aren't alot of rockets. :)

Take a look at this article for way too much information about orbital solar power.

Basically microwaves can be transmitted through the atmosphere without too much trouble, while building stuff in orbit is incredibly expensive. It might be possible to create an orbital relay station to deal with issues like focus, assuming that's a problem.

The fact is, wings and the structure reinforcement to allow wings costs weight. Weight which could as well be fuel.

There are some articles on SSTOs here and here.

The fact is, wings and the structure reinforcement to allow wings costs weight. Weight which could as well be fuel.

There are some articles on SSTOs here and here.

Not a problem on ascent - most liquid-propellant boosters are almost flimsy - little more than balloons. They avoid heat problems by getting above as much of the atmosphere as possible as soon as possible (which is why rockets launch straight up instead of almost horizontally - to reach orbit the horizontal component of the vector is the only thing that contributes. The vertical component of the vector is just to get you clear of skyscrapers, mountains, and of course, the atmosphere).
Re-entry is the problem, but the "shuttlecock" design of Rutan is a partial solution, combining that with better heat shielding might be enough.
Take a look at old plans to turn the old Saturn S-IVB stage into a Single-Stage-To-Orbit Space vehicle - The numbers seem right:
http://www.spacefuture.com/archive/a_single_stage_ to_orbit_thought_experiment.shtml

A not so well known company actually makes a floating platform that can launch rockets. It's heavily funded by Boeing, and advertises equatorial launches:

http://www.sea-launch.com/

Another interesting note is that there are a lot of complaints on the net about how the US government, according to some at the behest of NASA to keep the shuttle viable, has stiffled commercial launches. Here is an interesting site discussing the affect of the laws:

http://www.spacefuture.com/archive/barriers_to_spa ce_enterprise.shtml

True on one level, false on another.

Yes, NASA did much of the basic research.

But that was all done decades ago.

Does that mean they should have a permanent monopoly on space?

If this had been a NASA mission, would it not have cost ten times as much? And that makes it pretty much impossible to go to space for any reasons other than big-time investments like satellites.

I thought How the West Wasn't Won was a very nice parable on this subject.

D

Having something go up to the edge of space and back is relatively easy compared to going into orbit then coming back down again.

For the technically minded, here's a short article with the specifics.

"Let's just hope that the space-flights stimulate some competition, unlike Concorde, because then the next goal would quickly become 'lunar city'..."

Fortunately for you, the Japanese have been eying this industry for quite some time. And quite frankly, I'm putting my money on the culture that presently makes: The world's fastest super computer, the most reliable cars, the most advanced communication technology, etc...

These guys are in it to win and Virgin won't be able to charge $190K because the Japanese will be there offering $185K, or some other competitive number that would make it cheaper to fly vial JAL to Tokyo instead of Virgin to London.

The reason removing money from NASA (or from the government's involvement with technology generally) will rapidly increate technology development and deplopyment should be obvious, but it isn't unfortunately.

Here's an illustration:

I was present at a meeting in the early 1990s between Los Angeles venture financiers and a rocket company attempting to put together funding to activate some crated-up MX missile production facilities so they could produce cheap launch vehicles. That was the day the McDonnel Douglas decided to release news they had been given capital BY THE GOVERNMENT to develop the DC-X reusable launch vehicle.

The venture financiers left.

The first question that comes to mind is, does plasma research benefit from being carried out in a natural vacuum environment rather than needing apparatus to create one artificially? How does the degree of evacuation inside a fusion containment vessel compare with that in LEO, far orbit, or on the Moon?

This page states a typical pressure of 10^-7 atm for the interior of an operating fusion containment vessel. It refers to this condition as a hard vacuum, which this page defines as "a vacuum that approximates the vacuum of space." This page states an atmospheric pressure of 3*10^-9 atm at an altitude of 150 km, which isn't even LEO. (Al Shepard went more than 3x higher, and that was still a suborbital flight.) IANAHEP, but this would seem to indicate that taking advantage of the vacuum of space wouldn't be a bad idea. (The sticking point would be getting the other heavy equipment up there, along with a power supply.)

I listened to some guy on a radio show a few years ago touting this idea. He wanted to have hilton hotels be the sponsor, and reuse the shuttle boosters as building blocks. I googled this now and found this about the hilton hotels, and this on reusing the shuttle tanks I think the latter is the guy I listened to on the radio. His idea makes a lot of sense, the shuttle booster tanks are pretty clean after expending the fuel, and are there for the using with a little attitude and altitude adjustment. Big ole nice structures going to waste.

I think they're reading about the settlement of the western frontier of the United States of America. A mobile platform is an analog for the covered wagon, a caravan of which is effectively a trackless train. I also mention this because an essay contrasting NASA with western frontiersman was circulating for awhile. It was a critical piece, but it may have sparked some ideas, too.

-Hope

I dont know many model rockets powered by Peroxide. I also dont know of many that are capable of going to 131 feet and returning to within 1 foot of their launch point vertically (VTOL), meaning full flight control on takeoff, hover, and landing, and all with the click of a button. This rocket demonstrated the control authority they have now with their vane controlled engine, and their flight control system software. Basically he clicked his mouse, the computer flew the rocket to a pre-determined altitude and returned it to the ground under power.

Sorry, but this is advancement. NASA tried something similar (DC-X/A), but way bigger, took them several years to get it to even take off, and eventually blew it up, all at a much much higher cost ($40mill?). This "Large freakin model rocket" has been developed by a much smaller team, for what Im sure is alot less investment, and proves that their approach to a re-usable rocket can work. This is also their small scale vehicle. They have a larger one using the same technology and systems that they are testing as well. Rather than risk damaging it, they test everything on the smaller one until it works correctly. Read their website (once /. effect wears off), you might actually learn something.

Tm

...these would be providing around half of our power already.

You could smelt Al at ten times today's rate with approximately zero pollution related to power production, or better yet smelt it at source and drop shaped Jumbo-sized billets of pure Al (or alloyed to taste) into a big artificial lake somewhere at regular intervals.

If you're worried about transmission leakage, why not just build a conductive pair of these to carry the electricity directly?

No that's not the reason, just pick a medium that can be focused. I'm sure you can transmit power wirelessly using microwave or laser very long distances. (Consider that nearly all of the energy we use on Earth has been "transmitted wirelessly" from the Sun).

The problem is safety - if anything or anyone happens to be in the path of such a transmission, they get fried.

Here's a link about using microwave to transmit power from the moon.

IIRC he complained a lot about the awful smell. Although I couldn't find anything directly related to that, in this report he talks about related problems (vomiting, waste disposal).

You like the number if ifs and mights in that sentence enough to put bucks into the fusion project? Use your own. Unless the university researchers can point at a working He3 reactor,they are wasting our time.

The price to first power for a 250 Mw SPS is estimated at $10B using launchers we don't have yet with a $400/kg cost to orbit. However, the price to first power using Russian launch vehicles available now (roughly $4000/pound) shouldn't be more than roughly 10x that... i.e. building one should be no more expensive than the War on Iraq has been so far. Once we know it works, we can expand it using cheaper launch systems like the Space Elevator or railgun technology, hopefully including railgun launches of raw material from the moon. (cheaper than earth in terms of energy, if you don't know why, what are you doing here?

Which would we get more security from, a technology being actively researched that'll make the Middle East unnecessary or a war that at best, secures part of our energy supply for a few years?

The real prize is not the 10M purse, but the tourists that will follow. Some estimates are that the global market is in the billions. Several studies have been done indicating that people would spend 10k-100k for a trip, among people financially able to pay that.

I look forward to the day when a flight to space is a mundane vacation activity for rich people, right there next to hang-gliding rides and zorbing. Of course orbital is much harder, but the X-prize lays the first brick on that path.

-- Bob