[You'll make more sense of the title if you've read The Mote in God's Eye, by Larry Niven and Jerry Pournelle (ISBN 0 586 21746 0). But that doesn't affect what I'm saying.]
In early 2001, I knew there were folk planning (and they made an abortive attempt at it in 2005) to use a redundant nuke-delivery system to put a solar sailing vessel up, in orbit 85 kilometers above planet Ocean, and play; while someone else is planning on putting a hot air balloon 40 kilometers up (now, me, I'd be using Helium, but I guess they have their reasons). The former needs rocketry, but makes it to orbit: the latter doesn't. The gap between the two comes in two parts:
well, 50 kilometers or so. That's roughly half a mega-Joule per kilogramme; only slightly more than the energy (per unit mass) needed to get up to 40 kilometers in the first place.
a bit under 8 kilometers per second – orbital velocity anywhere near the surface of the planet. (For the SI-challenged, that's only slightly under 5 miles per second, or 18000 miles per hour.) That's roughly 32 mega-Joules per kilogramme. You'll notice it's a lot bigger than the altitude's contribution; rather to my annoyance. But only by two orders of magnitude.
So the big question is: can we bridge the gap ?
The Crazy Eddie Project says: OK, let's go for it. A Crazy Eddie doesn't worry about little difficulties like the speed part needing as much energy as would get the payload to an altitude equal to the Earth's radius (i.e. to twice as far from the Earth's centre as the payload started out), 6.4 Mm (4000 miles).
So H.T.F. ? Well, the ISO 9000 answer is what NASA's working on, so I shalln't waste my time on it. Either NASA succeeds (yippee) or not. No point the rest of us (aside, perhaps, from ESA and their other peers) wasting time duplicating that: it is, by nature, a big corporate solution applicable only by a big corporate player. But the attentive will notice that the ISO 9000 (and however many) approach doesn't leave much room for Crazy Eddie; and one of humanity's Big Wins is giving Crazy Eddie a chance. Human Crazy Eddies have a perverse tendency to (die in very large numbers while a few) succeed. One could argue that we wouldn't have made it this far otherwise. I could argue that our species will (mostly) be archeological record within a hundred years unless we give the Crazy Eddies an opportunity to die, in large numbers … while a few succeed. So how do we give them the opportunity ?
Well, that's easy. We know both boundaries.
If you can make it to 85 km and orbit, you're done. You can sail away, find an asteroid, mine it into oblivion, build yourself a cylinder ship and start work on building an eco-system. Sure, that'll take a lot of effort and most attempts will fail. But we only need one success (albeit my reckoning is we need it within the next 50 years, or we'll have fscked Ocean's eco-system so much we'll be on the archeology track and can forget about getting Crazy Eddie's help). But it's just engineering from 85 km upwards, as long as the Crazy Eddies can get there. OK, so ISO 9000 has a harder time, but that's NASA's (and ESA's, once the USA's economy goes splat and us Europeans are left carrying the torch – we can't rely on China to bother when it gets to their turn, which will be next) problem.
We can make it to 40ish km, albeit at no useful speed; NASA sent a guy up in (a space-suit, in a a basket under) a slack-bag helium balloon back in the 50s. Private citizens can now afford the equipment to do the unmanned version of that. For the sake of discussion, I'll say we do that with Helium in a slack bag, but if Crazy Eddie wants to do it with hot air I'm not complaining. NASA can do it with rocketry and so can some of the big corporations; but Crazy Eddie is going to do it by balloon, kite and, just maybe, aircraft like Helios – thank you, NASA. (Crazy Eddie will use those because they're within the budget of more-or-less ordinary citizens; the Crazy Eddies may not be discernibly ordinary, but their budgets are on the same scale as those of ordinary citizens.) So how do we pick up the 8 km/s of speed and the (comparatively trivial) other 50km of altitude ?
My basic plan is to give the Crazy Eddies of this world something to play with. Trust them, the small proportion who don't die will amaze me – and I'm gullible, so hard to amaze – unless, of course, I make it into the honorouble company of early deaths. The dead aren't noted for being amazed by anything. But I'm Eddy, not Eddie.
So we can put pretty much anything we like up to an altitude of 30 to 40 km. Of course, if it's heavy, it's going to need a lot of Helium. And if it's alive it's going to need to take its own Oxygen and food, which is going to require yet more Helium. For the moment, let's say we bung up a bunch of Helium balloons supporting a structure off which we can hang a bunch of solar panels, robots, radios and computers. Since the obvious building material for the structure is balsa wood, I'll call the station Kon Tiki.
Thor Heyerdahl was my favourite Crazy Eddie; I don't have an ISBN for The Kon Tiki Expedition (published by George Allen and Unwin, 1950) translated from Kon-Tiki Ekspedisjonen (Gyldendal Norsk Forlag, 1948); but a bunch of crazy vikingær sailed across the Pacific in a stone-age boat. Then again, Thor proved that anyone who's ever moved a fridge without picking it up is smarter than the folk who said there's no way Easter Islanders could have moved those huge stones from that quarry to where we found them. Go figure – my money's on Crazy Eddie.
So, as NASA's accountants will tell you, that's totally useless. The kit on the Kon Tiki will be cooked by radiation and as soon as it sails over the airspace of an unfriendly power it'll get shot down. What's worse, some libertarian geek is going to go up there in a balloon, ponce about a bit, break the balsa wood structure, and die (of radiation effects if nothing else); then their estate is going to sue the arse off whoever put it up there.
On the other hand, I didn't invite the idiot, and once I've been bankrupted by his estate (if I can't persuade the court that his idiocy was … well, his), Kon Tiki's still up there (and I don't have the funds to be forced to bring it back); and it costs more to fly a shoot-down mission up to 40km than it does to put up another balloon. If my robots can't fix the damage, some other Crazy Eddie probably can; and some of them will be putting up better Kon Tikis anyway, so who cares if mine gets broken. Helium, slack aluminised bags and balsa aren't expensive. There's folk who will positively volunteer to provide the robots and computers; and they'll understand that they need to provide the solar panels and radios, so no problem. The Crazy Eddies will positively brinkle at the court case or unfriendly fire, so there'll be dozens of Kon Tikis after the first gets downed.
But, as NASA's accountants will still tell you, it's still useless. At least to an ISO 9000ish scheme. On the other hand it's a positive dream come true to the Crazy Eddies. How much does a day or seven's supply of Oxygen (and food) cost ? Helium's cheap, so are slack bags. OK, so a space suit is kind of an issue, but take a look at how crazy pioneers can be. Improvise and almost fail to die gloriously – that's practically the slogan of the Crazy Eddies. So every now and again one of them actually does fail to die. Not as glorious as the rest, but even the Crazy Eddies will be copying whatever the survivors did. Usually.
Coming home ? Well, hell, that's practically the whole point. All you need
is a parachute (only, please, bring your rubbish home with you, OK ? The Kon
Tiki can only carry so much dead weight). And folk are going to be paying to be
lobbed up on rockets to get a chance at
space-diving, so the home journey
is going to have so much kudos. The ones who die up there are going to
get shoved off by the next visitors to reduce load; and you don't need
to book a place 'cos, by the time there's too many visitors, there'll be plenty
of them putting up their own platforms – which cost only a small fraction
of the cost of surviving up there for a week.
Worried that someone will nick the hardware you've put up on your platform ? Get real. It'll cost them more to get to it than it's worth; and you'll have video of them doing it – webcams are light and uncomplicated, so there'll be several on board – so it's not like they've any chance of getting away with it.
Eventually, NASA's accountants are going to notice that more folk are
getting a taste of
space this way, for ridiculously less cost, than they
can hope to achieve via rocketry; and some of them won't just be going up for
the ego-trip (and the buzz of falling home from space), they'll actually get
round to doing some science while they're up there. How light can we make a
telescope, anyway ? Astronomy doesn't love the troposphere (that's the bit of
the atmosphere that's so thick we can breath it) half as much as thee and me
– and 30km is clear of way more than just the sodium glow.
But still it's useless, 'cos you can't get anywhere from here.
But think of the fun you can have, during your stay, playing with kites. For one thing, the Kon Tiki is otherwise meandering at the whim of the wind, thin though the air is up there. Crazy Eddies are just going to need to interfere with that whim. For another, you can fly kites below yourself. That's cute in itself. And, of course, you don't have to be up there (dying quietly of radiation poisoning) to fly kites: you can always send up a robot. Like, I can't stop you, now can I ? Especially once the Kon Tiki is over Chinese air space.
The materials needed for solar sails are here: think what fun you could have putting them into a really heavy wind. Well, OK, the troposphere would rip them to shreds; but how about 40km up ? Moderate adaptations could be great fun.
How much kudos would there be in dragging the Kon Tiki up a few km higher than it was before you started flying your kite ? Or in playing with ways to launch something from the platform ? OK, so some of the idiots will trash the platform but, hey, how soon will someone put up another ? or mend the first ?
But that's still useless, even if you could make it up to 100km, 'cos you don't have the speed. Did I mention that the kinetic energy problem is two orders of magnitude bigger than the potential energy one ?
Kites can only zoom as fast as the air; and the solar light pressure is puny. (In the statosphere, you can't exploit the solar wind, but even if you could it'd also be puny compared to even the stratosphere's negligible air resistance.) So how do you pick up 8 km/s of speed ? Preferrably without rocketry. I have to admit I have trouble with that one. For now. But I believe in giving lots of Crazy Eddies somewhere to play: you'd be amazed at the results they get on their good days.
If you can get the speed up, you can surf on the upper atmosphere – sort of the inverse of skipping off the top of the atmosphere, which plagues re-entry for de-orbiting manoeuvres. But how do you get the speed, sustain it and grow it ?
Meantime, someone somewhere has put some junk into orbit and needs to de-orbit it. What a waste of energy. See if you can't dangle a long piece of bucky-string (well, hell, we don't yet have ultra-light string made of Buckminster-Fullerenes, but how long need we wait ? and some of our existing strings must be pretty good, for the solar sailers to be getting competitive) off the end of one of those – or off a passing solar sailer. Grabbing it will be kind of hard – it's going past at 8km/s, after all – but if you can do it, you can apply drag to it as it flies through your fingers (which are probably some spinning wheels which grip it, to whose axles you apply slight braking forces) and that drag on it is propulsion for you. Each time it passes you, in its orbit, take another drag on it (hell, it may need to reel the string in each time and throw it ahead of itself as it approaches you; but is that so hard ?). You go faster; it slows down (but, if it's a solar sailer, it can make up the difference by the next time you meet). Just like a kid whipping a top up to speed ;^>
We may not be able to do it, but that never stopped the Crazy Eddies trying.
The altitude shift, from 40 to 90 km above Earth's surface, is less than one
percent of Earth's radius, consequently the gravitational potential
centrifugal force acting against gravity change by less than one
percent; the gravitational force meanwhile changes by twice as big a fraction
(R.R.d(1/R/R) = −2.dR/R), roughly 1.6%, but still essentially
negligible. Orbital speed w.R is sqrt(G.M/R) so changes by less than half a
percent over the same range; it's 7.90 kilometres per second or 17,700 miles per
hour. That's 17 times the speed Earth's spin gives the equator, two and a half
times the speed of geosynchronous orbit and slightly over a quarter of the speed
of Earth's orbit around Sun.
Some guys in Lancashire seem to be playing with some similar ideas, as a memorial to a late lamented friend of theirs, Carl Nelson.
I've also seen reports of someone planning to make helium-filled wings and fly up the stratosphere – first using conventional aircraft engines to reach a Big Wing high in the stratosphere, then using an ion drive to climb the rest of the way. They quoted a figure of dollars per kilogram per mile of altitude, which likely makes all of the above redundant. Which will be a good thing, if they make it work.Written by Eddy.