Leonard David has an article in today’s Space.com on the rapidly-approaching feasibility of a space elevator. Apparently, rapid advances in the manufacturing of buckey-tube-based materials of unprecedented tensile strength are making this a viable near-term technology, which in turn makes it possible to build a tower to the heavens.

The basic concept is that if you place a satellite in geostationary orbit (where most communications satellites reside) it will, by definition, remain at a single point over the earth’s surface (at the equator). Drop a cable all the way down thousands of miles to that point, and tether it (just as suspension bridges often start as a single cable across a gorge). Now beef up the structure, and put the center of mass of the system beyond geostationary altitude, which puts it into tension.

Build elevators into the structure, and you have a means of getting into space for the costs of the energy alone (plus, of course the amortization and maintenance costs for the elevator). This is just a few dollars per pound, which is orders of magnitudes less than the current methods of using rockets.

That would make a space vacation possible for almost anyone who can now afford a trip to Hawaii. It would also make space a much more practical location for the storage of nuclear waste and the construction of solar power satellites that might eventually render nuclear plants unnecessary.

Unfortunately, as was brought home most dramatically last September 11, it would also make the most visible and monumental target possible for a terrorist.

The potential energy in such a structure would be unimaginable (though not incalculable). If it were somehow released from its equatorial mooring (in addition to the tremendous loss of capability and loss of life of whoever was on it), it might whipsaw around the local landscape like a python on meth, potentially causing tremendous damage on the ground before finally drifting out into space (where it would become a major navigational hazard for orbiting satellites, facilities, and even tourist hotels). It’s possible (though unlikely) that it could even ultimately strike the Moon. It would make the events of last September look like a Sunday-school picnic.

This is, of course, not an argument against doing it. But it does add some additional requirements for its construction that might not have been considered prior to the WTC attack. For instance, the structure near the base should probably be capable of withstanding a small nuclear detonation, if possible. It should certainly be capable of withstanding a collision with any existing aircraft (including supersonic). Security in the area should be strict (at least as far as explosive devices go), with a large keep-out zone on the ground and in the air.

I might be using this as the basis for the Fox News column tomorrow, so I’d appreciate any other thoughts that people have on the subject.

[Update at 5PM]

OK, having given it a little more thought, it seems to me that the problem with the article was that it didn’t mention any of the problems. It was gung ho about how the technology to do this is almost here, which means to me that we now have to give some serious thought to the real showstoppers.

I see two serious issues, either or both of which are likely to keep this from happening for a long time, and perhaps forever.

First, if a structure is towering from the equator to a third of the way to the Moon, no objects can safely orbit the earth at any altitude below that. No GPS, no remote sensing satellites, no space stations, nada. The only satellites that can safely orbit are the geostationary comsats. The reason for this is that all other orbits will eventually intersect the structure, resulting in a spectacular collision, unless they are managed carefully, and they can’t be managed that carefully–such an accident is inevitable.

The second problem is the one that I mentioned above, and it’s potentially much worse. If it breaks off in space, while the part above the break will go flying off into an elliptical orbit, or perhaps out into the solar system, the part below will come crashing down to earth. Much of it won’t burn up, because it won’t have much velocity.

So, as technically neat as skyhooks are, I have trouble seeing any political conditions under which such a risky project, requiring the total obsolescence of our existing orbital infrastructure, to fly. We are going to have to continue to work at creating new markets that can drive down cost of the launch rocket-based space transports, because I think we’ll be stuck with them for a long time.

Of all sources, the Guardian informs us that the US is moving its Gulf HQ from Saudi Arabia to Qatar.

My only question is, what took them so long?

Thanks to a suggestion by Jeff Goldstein, I’ve decided to make my blogspot watch script available.

All I ask is that you give me credit, and provide a link to my page if you decide to try to implement it. I make no guarantees…

A Munich man was investigated for murder after his neighbors reported seeing him carrying a corpse into his apartment.

When the police entered the place, he showed them (not clear whether it was with any degree of pride) his collection of inflatable bedtime companions.

I’d seen another story about this, and didn’t get around to posting on it. Ken Layne was more diligent over at Fox News today.

Saddam has given a pay raise to the families of Palestinian suicide bombers. Other than that, there’s no known connection between the Iraq regime and terrorism. Well, if you ignore the Prague meeting. And…

But I guess Chris Matthews thinks that it’s OK to pay people to murder civilians, as long as they’re just Israeli civilians.

Instantman points out an amusing post by Happy Fun Pundit (who I really have to permalink one of these days, albeit with an asterisk, as he’s a blogspottie) about Hollywood egos and the Academy Awards, and the fact that they aren’t all that popular in the “Red” states that voted for Bush.

I’ve never understood the cult of celebrity. It’s always been fairly obvious to me that rising to the top of Hollywood is mostly a matter of luck. Looks and acting ability are certainly necessary, but there are many more people with those qualities than jobs in the industry or room on movie and television screens. If all of Hollywood came down with some kind of plague, replacements would appear within a year. Certainly brains are not a requirement, judging by some of the asinine things that some of these people do and say.

Anyway, I was amused at all of the egotistical concerns about security for the event, as though it would be bin Laden’s highest-priority target. I suspect that if terrorists were actually stupid enough to attack this parade of (fortunate) pompous blowhards, at least half the country would cheer.

It’s long been known that people aren’t very good at aligning their fears and emotions, and resulting behavior, with statistics. For example, the chance of dying in a car is much greater than in an airplane, but many more fear to fly than to ride. Even people who are numerate are prone to this quirk of human nature (e.g., the great science fiction author and chemistry PhD Isaac Asimov had a severe fear of flying, and always traveled by train). On the other hand, people vastly overestimate their chances of winning the lottery, at least from a rational expected-value perspective.

I’ve occasionally talked about the dangers of asteroids in this weblog, and in fact featured it in my Fox News column last week. I’ve seen quite a bit of skepticism on the issue, some of which may be justified, but it often appears to me to be driven as much by the non-rational parts of us as the rational, even when coming from scientists.

When coming from politicians, of course, it’s even worse. A couple of weeks ago, an Australian cabinet minister ridiculed people who were concerned about asteroids, and refused to allot the paltry sum of a million dollars in order to look for them in the Southern Hemisphere, one of our current major blind spots. There are many sky surveys being done above the equator, but very few below.

It actually reminds me of the controversy of a couple of decades ago, when Luis Alvarez at Berkely first put forward his theory of dinosaur extinction being caused by an extraterrestrial impact. While it’s become fairly well accepted today, many aren’t aware, or have forgotten, that there was a tremendous amount of resistance to it when it was first propounded. And that resistance seemed to go beyond rational scientific argument–it seemed almost religious in its fervor.

Viewing this as a college student, who was interested in and familiar with space, I found nothing exceptional about the theory at all, but it was clear to me that much of the scientific community had a deep emotional investment in not believing that our planet could be so dramatically affected by an event beyond our atmosphere.

I’m not sure why exactly, but one might speculate that, to a planetary scientist used to thinking in terms of geological and biological processes forming and reforming the earth and its inhabitants, invoking forces extraterrestrial perhaps had the feel to it of the supernatural–a blow literally from the heavens, and one from a source with which they were (not being astronomers or extraplanetary scientists) unfamiliar and unknowledgable. It may have almost seemed like a creationist theory of evolution.

More practically, to accept such a concept might imply that their chosen field was much broader than their traditional education, and that much of what they had been taught was wrong. It was probably a natural resistance to a major scientific paradigm shift.

Fortunately, unlike actual creationist theories, it was testable, and evidence for it has been found, and now, after a quarter of a century, it’s now taught as the prevailing theory.

Anyway, there’s an interesting article on this subject in Space.com today, that has some interesting statistics on the subject (though I can’t vouch for them). Anyone whose interest has been piqued by my previous comments on the subject will find it at least as interesting as mine.

Basically, the thesis is that we base our fears not on analysis, but on what’s familiar. Prior to September 11, few took the terrorist threat seriously–now concern about it is very high and it can command huge numbers of societal resources. Hopefully, it won’t take an asteroid strike to get similar motivation to map and deter potential cosmic threats, but judging by human nature, it may.

Krauthammer has a piece in (be still, my heart) the WaPo about the notion that the spate of suicide bombings in Israel over the past decade are not the fault of that nation, but (gasp!) Yasser Arafat.

It is precisely in the context of the most accommodating, most conciliatory, most dovish Israeli policy in history that the suicide bombings took hold.

Where, then, did they come from? During the past eight years–the years of the Oslo “peace process”–Yasser Arafat had complete control of all the organs of Palestinian education and propaganda. It takes an unspeakable hatred for people to send their children to commit Columbine-like murder-suicide. Arafat taught it. His television, his newspapers, his clerics have inculcated an anti-Semitism unmatched in virulence since Nazi Germany.

Up is down, in is out, and Canada has come out with a sensible recommendation set for hijacking procedures (despite the reporter’s hysterical description).

The most dramatic proposal advises the government to adopt a public position of non-compliance with hijackers, a hardline stance that would force pilots to ignore terrorists’ demands even if it puts passengers at risk.

Currently, air crews are trained to negotiate with hijackers and acquiesce to their demands when passenger safety is threatened. The new approach recommended by the working group would instruct pilots to land the plane as quickly as possible, regardless of what hijackers are doing to passengers.

The new policy was recommended because the suicide hijackings in September dramatically changed the dynamics of airline terrorism. Since then, pilots have been working without any new instructions on how to deal with hijackers, although many vow to never give up control of the flight deck after having seen commercial airliners used to bring down the World Trade Center.

But non-compliance creates the horrifying scenario of pilots, locked in the cockpit, refusing to cede control of their aircraft even as hijackers torture or kill passengers in the cabin. It is also thought that, in some situations, firm non-compliance could escalate confrontations with hijackers who are not suicidal.

This, of course, assumes that the passengers will just sit by as greatly-outnumbered hijackers kill or torture them. This seems like an unrealistic scenario, post 911. At least, on American (the nationality, not the airline) aircraft. I suspect that ordinary Canadian citizens also have more spunk than this comment would give them credit for.

Hey, is there any constitutional reason that we can’t get a Canadian to replace Norm Mineta?