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What part needs magic materials? The ribbon is made of soft iron iron or steel, probably woven in a manner not unlike normal cables, or possibly in solid sheets. That's not exactly difficult to make. The sheath is a kevlar or carbon fiber composite with an aluminized mylar liner. The control magnets are copper windings over soft iron. You didn't actually read any of the papers, did you?

The tethers holding that sucker to the ground. Did you think of doing a back-of-the-napkin calculation on the tensile strength needed to hold this sucker down???? We're talking orders of magnitude beyond the best artificial spider silk to hold this thing down, and I don't think you can quite order that up in industrial quantities yet.

What part of "mega-scale engineering project" made you think this would be small?

What part of 'too goddamned big and expensive to be economically feasible in our lifetimes' do you not understand? Especially since you'd have to build the sucker in order to test its viability. I'd guestimate it'd only cost a couple trillion dollars, so wait a few weeks for the economy to finish pancaking before writing the check; you'll get your money's worth then. I'm supposing this will be a government project, nobody else would have the cash and the desire to pull this off (although there's bound to be a few private sector entities that could concievably get the cash together, I wouldn't count on their stockholders allowing them to spend it on something like this), which means it won't come in anywhere near budget or on schedule. Yes, I've done heavy construction in my younger crazier days; it put me through college.

Oh, and don't count on selling this to Congress unless you can do like Ike did with the interstate highway system that came about in the 60's & 70's.

Contrast this to a laser launching system. For a few million, you can do a real-world feasibility study. Hell, Lightcraft Technologies already did a feasibility study using a 10 kw laser to push a 25 gram weight to 200 feet as a test. The test worked. Show me a comparable feat with your launch loop.

Look, I keep beating this same drum over and over again - but the answer to this problem (and many others!) is to give http://www.lightcrafttechnologies.com/ about a billion dollars to get themselves off the ground (no pun intended).

Corresponding with Liek Miyabo the company principle - he maintains that a pulsed 1 Gigawatt laser will put 1-ton payloads into orbit for cents per kilo. The same "laser beams" can be used to de-orbit space junk. As they come over the horizon, you blast the stuff with Laser light. The light pressure exerted on the junk slows it down, and drops its orbit. Major parts can be bought down quickly, other (smaller) bits can be bought down over months and years.

There is a global database of (known) space junk, and their orbits - so it should be simple math to program idle launch lasers to bombard space junk during down times.

Not only does the launch system allow for de-orbiting space junk, and launching hardy materiel into LEO, but it will also perform the following functsions:

1) Reflected from orbit not pulsed but defocused to illuminate search and rescue locations
2) Reflected form orbit, not defocused: surgical strike weapon capable of slagging your neighbours house without scorching your fence.
3) Bug eyed-alien tamer extra-ordinaire: several pulsed gigawatt class lasers say "Don't fuck with me" on a large scale.
4) Light-sail motor: boost interstallar probes to reletivistic velocities
5) Planet-killing Asteroid fixer: Only 2cm/s velocity change is required to change the orbit of an inbound asteroid such that it will miss the earth, even only 2 years out. Light pressure solves this one too.
6) Ballistic missile defence (REAL - as opposed to make-believe): this system will actually work, instead of merely providing employment for constituents of Senators in affected states.

So, this system actually does multiple things, and all for the same, low-low price, compared to Dubya's BMD program, which is a complete and utter waste of time and money.

Your microsatelites will be launched by Laser Beams: http://lightcrafttechnologies.com/

Oh, and a network of these bad boys would make a handy defensive weapon, reflected from space to make a surgical strike weapon, defocused for search and rescue missions, light sail accelerator, bug-eyed alien tamer, asteroid deflection system and high quality extrasolar signalling aparatus.

http://www.lightcrafttechnologies.com/

Disclaimer: I am a fan of Space Elevators. A BIG fan. Some very very serious problems have yet to be solved though.

I keep pimping the lightcraft thing because it is so logical and so beautiful: (short version)

1) 100% of launch mass reaches orbit. (Ok, 1% may ablate during the ascent)
2) Gigawatt class Lasers are 100% COOL.
3) Cents per kilo to LEO
4) Can you say "Anti Ballistic Missile Defence System that **SHOCK HORROR** actually works"
5) Entirely new industry created.
6) Laser can be reflected back from space to slag enemy locations. Surgical Strike weapon "par excellence".
7) Lasers can be defocused on orbit and used as Search And Rescue illumination at night time
8) Lasers can be defocused and used to illuminate work environments on the Luna surface at night.
9) Lasers will launch light-sail craft to relativistic velocities inside our own solar system for trans-solar robotic exploration.
10) Nothing says "Inbound Bug Eyed Alien Tamer" like 50 x Gigawatt class Lasers focused on a single point.
11) Lasers can be focused on inbound NEOs or asteroids to deflect them from striking the Earth. A change of only 2cm/s is required to prevent a collision. Light pressure rocks!
12) Interstellar laser-based messaging system, with Gigabyte/second class bandwidth.
13) Megatons of payload into LEO every year.
14) system operates 24/7 in any one of the above jobs.

Simply put, there are no technical hurdles to this system. There are already lasers in the 50 megawatt range - all we need to do is develop pulsed lasers at an order of magnitude more powerful. That should be no problem at all.

As to the defensive (In the USA read as "Offensive") capabilities of this system, well, I've had numerous emails with Liek Miyabo about this, and he refuses to discuss these options. To me, this indicates interest by the US military. Hell, if I were Bush (which, thank God, I'm not!) then I'd be all over this technology. I guess the erason there hasn't been a coupel of billion thrown at it, is that there's very little pork involved, or the research is happening in a (D) state. :P

Exotic High Risk Projects?

Clearly you are NOT American, because it is very obvious to any outsider looking in that the USA will no tolerate any reasonable level of risk at all. Look at the stink when just 7 people die, and only a 2 Billion dollar shuttle is lost? Hell, 7 people is nothing - and Dubya it chucking a billion a week at Iraq - and ALL of those lives and dollars are completely wasted. I don't see anyone reviewing the Military budget (450 Billion) because people keep dying.

Hell, servicing Hubble - arguably the most successful space craft ever - was cancelled because people might die. I bet if you asked ANY rated astronaut if they're prepared to take the risk of servicing Hubble you'd get a 100% affirmative "We'll go!" answer.

No - the USA has turned its back on the pioneering spirit - and the whole "Earth, Moon, Mars and beyond" thing is a joke. It's going to be a debacle of the greatest kind: even worse than the ISS. Jebus, it's no even clear how to build a BDB (Big Dumb Booster) any more. The "Stick" so eloquently argued for is a multibillion dollar development, and not even remotely "using existing hardware" as advertised.

Don't get me wrong, I love the ISS, and if it costs 2 Billion dollars a shot to get my pretty 2560 x 1024 wallpaper - then that's a cost I'm willing for US tax payers to pay! Even if the ISS ends up costing 100 billion Euros, the experience of actually having worked together in space (and yes, many contries HAVE contributed) and the knowledge gained by assembling the thing probably almost justify the expense.

See the thing most of you have forgotten, is that you learn more from your failures than you do from your successes: and NASA has had plenty of failures in recent years. The problem is that NASA isn't being driven by an agenda which requires those lessons to be turned into conventional wisdom, and success!

Hell, it might cost a Trillion US dollars before there's any conventional wisdom about getting to LEO, and how to do things beyond LEO - and if it costs a trillion - or two trillion - or a hundred trillion dollars, then that's the price it costs to buy our way into this galaxy. No one is standing by, watching us, and they don't have a "Key To The Galaxy" waiting for us when we set foot on Mars. Escaping the doomed Earth, and populating the Solar System is going to be the most expensive venture ever undertaken by man. The effort may well cripple the Earth for a long time.

One thing is clear: whatever the cost, we need to know how to get off the planet reliably and cheaply.

Personally, I think sitting atop a million kilos of rocket fuel is the dumbest idea ever!

The future isn't rocket powered: it's laser powered: http://lightcrafttechnologies.com/ or its via space elevators. It most certainly does not make sense to burn 95% (or 99%!) of your payload just toget into orbit! If you're gonna burn fuel, the burn it on the ground.

Well, I'm all for megawatt class lasers - as this means the technology is about 1/1000th of the way towards using lasers for something useful: Beamed Laser Launching of hardware into space.

Liek Myrabo of http://www.lightcrafttechnologies.com/ has been developing beamed power launch technology for some years now. In my correspondence with him, he has estimated that a 1-ton payload can be launched into low earth orbit using a 1-Gigawatt class pulsed laser cannon.

This ground-based launcher is the ultimate tool, and if you build a ring of them around your country, you can be pretty well assured of having utter domination of not just the sky above you, but the skies above everywhere. The first to deploy the network wins the game!

There is almost no end of uses for this array of gigawatt laser cannons:

1) Beamed Laser launcher, with total cost to orbit of just cents per kilo.

2) Inbound missile melter, extraordinaire.

3) Extreme Bug-eyed alien tamer. Unfriendly invaders might think twice before tangling with a species capable of focusing better than 100 Gigawatts of energy at inbound bogies.

4) Surgical Strike weapon par excellence. Reflected back to earth via large space-based mirrors allows you to wave the thing in a decreasing spiral which will turn your neighbours house to molten slag, but barely singe your fence.

5) Galaxies' brightest Search and Rescue spotlight: defocused in orbit, and reflected to earth to illuminate areas currently under search and rescue operations.

6) Illuminate work sites on the moon during the long luna night. Defocused to make a nice night light back on earth.

7) Interplanetary messaging system: embed knowledge into the beam, and send it to likely looking planets. Long term payoff - unknown.

8) Asteroid deflection device: light pressure alone is enough to deflect an inbound near earth object. Just 2cm/s velocity change is enough to deflect most inbounds.

9) Interstallar probe launcher: lightsail driven robot craft accelerated to a decent %age of light speed in fairly short order.

I'm sure there are other uses too - but these would seem to be the obvious ones.

On a more practical note, with the number of competing vendors and the number of technologies in play, it's not a question of if but of how. Will the laser drives beat the chemical boosters but lose out to the space elevator?

Unless the dimwits with the guns and bombs manage to foobar our entire world, somebody's getting systems running in the next fifteen years or so. As an old L5 member I say, it's about damn time!

-Rustin

The easier, more exotic, load delivery mechanisms can be used only if the load is little. I thought no less than someone spreading all their value over many small successive launches than risk one heavy/expensive launch. It also appears that the cost of launching heavier objects into space will increase exponentially by weight! There is much development on laser-launch systems. I was looking for the earlier Slashdot article on laser technology, yet this webpage is just an independent collection of information regarding alternatives and does show some URLs for laser content.I don't see any shark stickers, so its troll safe.

Lightcraft Technologies, Inc. is a commercial venture.
Adrew V. Pakhomov appears to profess on the subject, and a host of a symposium.

And then there's lightcraft. Watching that video reminds me of the old Orion test footage. Mind you, the site hasn't been updated in some time, although I did get email from the CEO saying there was lots coming. We shall see.

I went through the thread with hot mod points, looking for a comment mentioning the one thing as cool as the Orion project and the /. standard story beanstalks.

Relax, people, military research is good! :-)

(-: But to actually build lots of the military stuff are usually a waste, though. :-)

Yes, the LightCraft is very cool, but it has several problems that limit it's practical applications.

One is that the laser required to launch it has to use so much power that it heats the air, which causes the beam to disperse. This puts an upper limit on the payload.

Also, it turns out not to be very effective once it gets high enough that the atmosphere has thinned out. The developers have had to add layers of ablative material to the inside of the cone lip to provide material that can be accelerated away from the craft to provide proplusion. It's debatable whether this counts as fuel because most rocket fuel provides both reactive mass and energy, but, in this case it provides only the reactive mass. Just like conventional rockets, this extra material places limits on the lifting power of the craft.

The Canadian SHARP microwave powered aircraft scaled very well. One version had a 4.5m wing span. There's a picture of it at the link above.

I suspect that the microwave rectenna system is more efficient than using a photovoltaic cell and would probably work better on cloudy days too.

The project that probably will fail due to scaling issues is the LightCraft. It'll require so much power that laser dispersion, air heating and other such problems will ultimately limit it's lifing power.

I remember something like this from several years ago...seems like it has actually turned into a company: http://www.lightcrafttechnologies.com/

Work seems to have stopped in 2000.

Thanks JohnFluxx. Let's try that again:
click here
click here
And BTW, this ~is~ the laser powered rocket n1ywb mentioned below. Myrabo pops up on the Discovery channel every couple of years. Unfortunately, his progress has been fairly slow. I read his book back when I was in Junior High. His big problem is using lasers. Both lasers and microwaves have their problems. I think it is a good idea, though, and I wish Dr. Myrabo luck. I recommend the book to NEone who is seriously interested in the problem of how to put things in orbit cheaply and safely.

Ah, an even better link... click on PHOTOS AND REELS for video...

Lightcraft Technologies

Why isn't Lightcraft Technologies discussed here?

Look in Google groups after e.g. 'Leik Myrabo' or 'lightcraft'.

It seems they never got enough money to get off the ground. :-(