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drscottI've been buying up vintage bolo ties on EBay. The cohort that liked them is dying and there's very little interest in them since they're so out now, so you can get nice ones in silver and stone for $15 or so.
In 1982 I did a series of short-term jobs to fill time before returning to school. One of them was at an odd little company near MIT called Electromagnetic Launch Research, where I was in charge of their little CP/M network.
The company's emeritus intellect was Henry Kolm, in his 60s at the time, an old coot of the best kind. Henry had done a lot of work on electromagnetic propulsion -- rail guns, mass drivers, maglev trains. He dressed in western shirts and bolo ties -- very much a character out of middle Heinlein. Among the many stories I heard from Henry were his demonstration of the safety of the Xerox toner he had helped invent -- he ate quite a bit. Which is of course no guarantee it's safe to breathe, which was the real concern, but he was so annoyed at the FUD of the time about it that he felt a public display was necessary.
I probably got that job because I had lots of connections to railguns. A railgun is a device to rapidly accelerate a projectile via magnetic force; the projectile is on a rail or magnetically suspended, and coils along the line of propulsion are pulsed to accelerate the projectile until it is released at terminal speed. In high school I had built a cheesy version which launched nails a few yards -- the "control system" was a progessively-spaced set of electrical contacts on a board. You launched the nail by stroking the power wire across the contacts at a steady rate! Not the most reliable system, but it usually worked. This was inspired entirely by Heinlein's The Moon is a Harsh Mistress, where lunar rebels use linear induction railguns to bombard the Earth in their effort to rebel against UN authority. Today's systems, of course, use sophisticated sensors and computer control.
At MIT I had taken a seminar in space colonization with Gerard K. O'Neill, the L5 saint. My project was a study of gentle redirection of Oort cloud comets for terraforming purposes. Railguns were one the means suggested for nudging the comets, and millions of them would have to be redirected to give volatiles to, say, Mars. Henry loved that idea.
None of the space colonization ideas were ever funded -- though we do have an albatross of a space station which is next to useless, leaking, and cost $20+ billion. Henry is still alive, and he's at least lived to see a few Maglev trains built and railguns incorporated into US military plans (see http://www.globalsecurity.org/military/library/news/2003/05/mil-030512-navsea04.htm).
Here's a paper on the original ideals: http://lifesci3.arc.nasa.gov/spacesettlement/spaceresvol2/electromag.html
In 1982 I did a series of short-term jobs to fill time before returning to school. One of them was at an odd little company near MIT called Electromagnetic Launch Research, where I was in charge of their little CP/M network.
The company's emeritus intellect was Henry Kolm, in his 60s at the time, an old coot of the best kind. Henry had done a lot of work on electromagnetic propulsion -- rail guns, mass drivers, maglev trains. He dressed in western shirts and bolo ties -- very much a character out of middle Heinlein. Among the many stories I heard from Henry were his demonstration of the safety of the Xerox toner he had helped invent -- he ate quite a bit. Which is of course no guarantee it's safe to breathe, which was the real concern, but he was so annoyed at the FUD of the time about it that he felt a public display was necessary.
I probably got that job because I had lots of connections to railguns. A railgun is a device to rapidly accelerate a projectile via magnetic force; the projectile is on a rail or magnetically suspended, and coils along the line of propulsion are pulsed to accelerate the projectile until it is released at terminal speed. In high school I had built a cheesy version which launched nails a few yards -- the "control system" was a progessively-spaced set of electrical contacts on a board. You launched the nail by stroking the power wire across the contacts at a steady rate! Not the most reliable system, but it usually worked. This was inspired entirely by Heinlein's The Moon is a Harsh Mistress, where lunar rebels use linear induction railguns to bombard the Earth in their effort to rebel against UN authority. Today's systems, of course, use sophisticated sensors and computer control.
At MIT I had taken a seminar in space colonization with Gerard K. O'Neill, the L5 saint. My project was a study of gentle redirection of Oort cloud comets for terraforming purposes. Railguns were one the means suggested for nudging the comets, and millions of them would have to be redirected to give volatiles to, say, Mars. Henry loved that idea.
None of the space colonization ideas were ever funded -- though we do have an albatross of a space station which is next to useless, leaking, and cost $20+ billion. Henry is still alive, and he's at least lived to see a few Maglev trains built and railguns incorporated into US military plans (see http://www.globalsecurity.org/military/library/news/2003/05/mil-030512-navsea04.htm).
Here's a paper on the original ideals: http://lifesci3.arc.nasa.gov/spacesettlement/spaceresvol2/electromag.html
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no subject
Date: 2004-01-09 06:49 am (UTC)<scifi-geek>
I must admit that I'm not up on my Heinlein. It sounds similar to one of the main events in Babylon 5: the destruction of the Narn homeworld by the Centauri fleet through the use of mass drivers. If you don't remember the scene, the Centauri war machines accelerated small asteroids toward the planet.
Clearly, even a small mass that survives an acceleration toward a populated planet has the potential to inflict a lot of damage. But it seems to me that there are lots of problems with such a strategy. The Earth, for example, is made mostly of water. To inflict lots of damage, the idea is to hit populated areas. So either you use lots of masses and hope they hit, or you have to guide the masses. How do you do that? In a nonmilitary application, it would be cool to be able to maneuver a small asteroid to a low Earth orbit and then drop it (or drive it) to a water target (say, an industrial bay) where the asteroid could then be processed for its minerals. The question here is, how do you guide a rock through an atmospheric entry to a specific location?
</scifi-geek>
You must have had a lot a lot of fun with your maglev project.
toner....
Date: 2004-01-09 06:50 pm (UTC)Re: toner....
Date: 2004-01-09 07:28 pm (UTC)And as for ingestion, the stuff is pretty much inert. Thus Henry's demo. The swarm of paid scaremongers we see today was small then, but they had targeted toner since it was relatively mysterious and a large number of people were exposed to it.
no subject
Date: 2004-01-09 07:43 pm (UTC)The mass drivers in the book were designed for shipment of canisters of lunar grain to be shipped to precise splashdown points on Earth. Aside from the slight implausibility of Moon-as-breadbox and shipping such low-value cargo, the canisters were launched at precise times, with precise velocities, with some hints that the trajectory could be tweaked a bit at the end of the launch tube. Along with the complete freedom to choose trajectories if time-of-flight doesn't matter, that's enough degrees of freedom to explain the assumed ability to target any point on Earth. In the book the lunar rebels target "demonstration" spots near cities and in harbors, and only do actual damage after an obdurate UN refuses to negotiate.
As for re-entry, a massive object with a well-designed ablative shield has a predictable trajectory in atmosphere. Variance of impact location is pretty small.