Recently I talked about one of my favourite blogs, Brian Wang's Next Big Future.  He and his team are a veritable fountain of ideas, and this week they've outdone themselves with a series of pieces on Project Orion and its offshoots.  Now, I freely admit that they've done all the heavy lifting here (so to speak) but I'm going to take one of their ideas and run with it anyway.

A couple of the salient posts on Project Orion are The Nuclear Orion Home Run Shot, and Pieces of a True Nuclear Cannon.  Now, Orion was the 1950s-era American project to build a nuclear-bomb powered spacecraft.  Three facts stand out about the project:

1. It could have worked, and would have put unlimited amounts of mass into space for less than $1 a kilo.
2. The biggest vessel contemplated by the Orion team would have weighed 8 million tonnes, and would have been bigger than the Great Pyramid.
3. The sucker wouldn't have incinerated, flattened, and irradiated nearly as much real estate as you might think.

Still, for some reason the project was canceled around 1964.

In contemplating the glory that almost was, it's tempting to imagine what could have been accomplished with Orion.  One thought I had was that, well, maybe you could just use it once:  do the full-out 8-million tonne monster and use it to launch, in one shot, enough solar satellite infrastructure to obsolete every North American coal plant overnight.  According to a rational moral calculus, if Orion works it should be used in such a way, because the number of people who would die worldwide from the beast's fallout would be trivial compared to the number saved by reductions in air pollution from coal.  (Three million people die from air pollution each year; what they point out over at Next Big Future is that Orion could be calibrated to limit its fallout deaths to no more than a few dozen per launch, even for the biggest ship).

Still, there would be some place on Earth that would suffer from such a launch, and one thing we've learned is there is no truly "empty" land.  Even if our moral calculus could be extended to other species that would be saved by greening our power, it would be better if there were some way to launch such huge masses without exposing the biosphere to nuclear explosions and fallout at all.

There is.  I call it the Verne gun because frankly, a name like THE ATOMIC CANNON would just not go over well in certain circles.  In any case, the principle is the same as Verne's original idea, but using modern technology:  you set off a nuclear charge underground where the blast, heat, radiation and fallout can all be contained, and use Orion-type technology to direct its energy into orbiting a very big, very heavy spacecraft.  This vessel would experience hundreds to thousands of g's of acceleration--you couldn't put humans in it.  But Wang calculates that a 10 megaton bomb could put 280,000 tons into orbit with zero radiation escape into the biosphere.  Since dozens of bombs were exploded in exactly this way from the 50's to the 70's, we know this can be done.  And Orion's researchers proved nearly every one of their theories about Orion.  What they couldn't test at the time can now be simulated accurately by today's supercomputers, without the need for a test program.

Such an orbital gun could be used multiple times.  Here's what you could do if you could put 280,000 tons into orbit in one shot:

• Put 1.5 terawatts of clean solar power into orbit with less than ten launches.  Obsolete coal and petroleum power production with green baseline power, using less than a 10th the number of solar cells as you'd have to install on Earth to capture the same amount of sunlight.
• Orbit an entire space elevator with one launch.  Set it up, retire the gun, and get on with a clean space age.
• Do the same thing with an orbiting greenhouse infrastructure.  Drop solar-powered mass drivers on the moon to feed a continual stream of building material to the building sites.
  
• Orbit fuel depots to drop the price of conventional rocketry to orbit through the floor.  One shot and access to space for NASA becomes 10 times cheaper.
• Send up a telescope so big that it can image the continents of planets circling other stars.
  
• Put up one or more of those cool gigantic orbiting space station wheels that are showcased so dramatically in the movie 2001:  A Space Odyssey.
• Send an entire colony's worth of material to the moon or Mars.  With a second shot, put up an interplanetary cycler ring, tether launch system or other permanent mechanism for shuttling people to and from the colonies.
• Toss a couple hundred thousand tons of nuclear waste into the sun, where it won't bother us anymore.  (Trust me, the sun won't notice.)
• Launch an empty Orion ship, send its fuel up the safer space elevator, and send an expedition to Saturn, or a probe to the next star.
  

I'm not going to suggest orbiting a sunshade to head off global warming, because that's no solution for problems like ocean acidification.  --In any case, you can certainly think up other cool stuff we could do; and notice that some of these options, like orbiting fuel depots or a space elevator, can easily bootstrap us out of having to use the gun more than once or twice.

Oh, and of course, there's one more thing you could do with it, but since you'd need to get signoff from all the members of the nuclear club to use it at all, this one's a bit less likely:

• Orbit a huge frikkin death star platform with ATOMIC LASERS and MISSILE RACKS and RAIL GUNS and aim them at anybody you don't like.