Dan Wiener wants to use space elevators to prevent hurricanes.

And if we could get them to lance volcanoes, Jonah Goldberg would probably get behind the project, too.

…and about a hundred million more to go. Liftport had a successful space elevator climber test.

Thomas McCabe fires a broadside at Bob Zubrin, with an article about the irrelevance of the Martian frontier.

Robin Snelson reports on the “losers” of the X-Prize competition. It’s a good survey of what’s going on in the suborbital world right now, and some of them could still end up being winners.

Also at today’s issue of The Space Review, Taylor Dinerman wonders whether NASA will renege on its launch deal with the Air Force (my money’s on “yes”). I think the piece is mistitled. The question isn’t whether NASA can keep up its end of the deal, but whether it will.

Also, Jeff Foust has a movie review from the premiere of Tom Hanks’ Magnificent Desolation.

Someone over at Free Republic (see comment #11) had an amusing comment on the space elevator concept, which brings up a serious issue:

So this elevator “would crawl up a single cable into space over several days.” How would people be able to not start up conversations for that long? Would they be allowed to make eye contact or would they have to look up at the ceiling? What if there’s a pretty girl on the elevator? And would they pipe in Muzak? These are the things that would have to be worked out.

For this reason, and perhaps safety reasons, even if elevators are built, they may be used primarily for bulk cargo, rather than passengers. Given my acrophobia, I know that I personally wouldn’t want to ride one–I don’t even like elevators in medium-size buildings, and you couldn’t get me into a glass one of more than a story or two on a bet.

I still suspect that there will be a market for reliable space transports to get people quickly to and from LEO. From there, cheap propellants made possible by use of extraterrestrial resources (and perhaps the elevator for more sophisticated equipment) will open up the other “half of the way to anywhere.”

Kevin Connors is arguing with Sir Arthur C. Clarke (the guy who invented geostationary orbit, and popularized the concept of space elevators) about the technical viability of the latter. All I can say is that he’s a braver man than I. He’s also a little confused about orbital mechanics:

…orbit in the Clarke Belt is achieved because the centrifugal force of the orbiting satellite exactly matches the force imparted upon it by gravity.

Well, this is sort of correct, but oversimplifed. In reality, there’s no such thing as a centrifugal force, but one can pretend there is in the rotating (non-inertial) reference frame. It’s more correct to say that the centripetal acceleration exactly matches that of gravity at that altitude.

Propelling a payload up a tether attached to that satellite would upset that equilibrium. Further, their is the distributed mass of the tether itself to consider. It is therefore necessary that the satellite be in a far lower orbit, in order to maintain tension on the tether.

This is where he goes off the tracks. I don’t know why he thinks a lower orbit would be required (or what he means when he says “satellite”).

A space elevator is designed to have its center of mass at a point beyond geostationary orbit. The idea is to have a balance between the forces that would provide sufficient tension in the cable. During construction, the anchor would initially be in GEO, but as the cable is dropped from it, it will move upward to keep the CM at GEO altitude, to maintain a geostationary period. Once the cable has reached down to earth, the other end is anchored. At that point, you’d continue to reel it out, but moving the anchor up to increase tension in the cable to whatever was desired, at which point the geostationary orbital period is maintained by being attached to the planet. The old conventional wisdom (if such a phrase makes sense in the context of a concept like this) was that one might use a small asteroid for the anchor. Newer concepts don’t require as much mass, but in either case, there will be sufficient mass, at a sufficient supergeostationary altitude to allow motion up and down without major issues.

Indeed, the path the transport vehicle takes to reach the satellite will not be a straight path, as is popularly envisioned, but a great parabolic arc.

Again, I don’t know what he means by this, but (also again) the path will depend on the reference frame. From the reference frame of a rotating earth, the path will follow the cable, which is to say straight up to GEO (where the weightless docking station would be, though the elevator structure would continue on to higher altitude, as described above). From an inertial frame, the path would appear to be a spiral, as the car orbits the earth once per day with increasing altitude. There will be some coriolis force on the moving car as a function of its velocity and altitude (as there is in an earthly elevator car), but the tension of the cable will be designed to be sufficient to prevent it from bending it much.

From a basic physics standpoint, the concept is fine, and can be easily simulated, honest.

While Andrew Sullivan makes many good points in this Times piece, in which he accuses George W. Bush of being a socialist, he damages his credibility, at least to those familiar with space policy, with this:

…when Katrina revealed that, after pouring money into both homeland security and Louisiana

Business 2.0 has a list of nine trendy fads to ignore. One of them is space tourism:

Travel to the final frontier is riskier than buying a vacation home in Aspen. When the first billionaire perishes in the icy void of space, it

More of a note to myself, if anything, to be expanded on later, in another venue.

It strikes me that NASA’s response to the president’s challenge is a statement of fundamental unseriousness about it.

A serious program to go back to the Moon, and beyond, would be based on a foundation of an infrastructure that would dramatically reduce the marginal costs of getting to orbit, operating in orbit, and getting to the points beyond low earth orbit. It would be a decision that would allow dramatic and affordable increases in space operations, for both the government and the private sector.

That they have chosen an architecture that makes the marginal, per-mission costs of doing anything in space as high or higher than they’ve always been indicates that they’re more interested in short-term milestones (getting back to the Moon and completing the lost missions of Apollo) than in opening up a frontier. I thought that I heard the president say something else over a year and a half ago, but perhaps, politically, they’re right, and I’m wrong.

[Update on Saturday afternoon]

Clark Lindsey has some expanded thoughts on this subject.

Jon Goff on trade studies, and why you can use them to justify almost any answer you want.