Huge 'Launch Ring' To Fling Satellites Into Orbit

A ring of superconducting magnets fires a projectile off a ramp at 8 kilometres per second, fast enough to reach orbit (Artist’s conception: J Fiske/LaunchPoint)

A cone-shaped shell would protect the payload during its passage through the atmosphere into space, and includes a rocket at the back end to adjust its trajectory (Illustration: J Fiske/LaunchPoint Technologies) An enormous ring of superconducting magnets similar to a particle accelerator could fling satellites into space, or perhaps weapons around the world, suggest the findings of a new study funded by the US air force.

Proponents of the idea say it would be much cheaper than conventional rocket launches. But critics warn that the technology would be difficult to develop and that the intense g forces experienced during launch might damage the very satellites being lofted into space.

Previous studies have investigated the use of magnets to accelerate satellites to the high speeds required for launch. But most have focused on straight tracks, which have to gather speed in one quick burst. Supplying the huge spike of energy needed for this method has proven difficult.

The advantage of a circular track is that the satellite can be gradually accelerated over a period of several hours. And the setup is technologically feasible and cost effective, suggests a recent, preliminary study of the idea funded by the air force's Office of Scientific Research.

The air force has now given the go-ahead for more in-depth research of the idea. The two-year study will begin within a few weeks and be led by James Fiske of LaunchPoint Technologies in Goleta, California, US.

The launch ring would be very similar to the particle accelerators used for physics experiments, with superconducting.

"And don't forget the part about screaming through the atmosphere at Mach 20+. The thermal requirements are gonna be killer. "

I've read a plan where they planed to do this up the side of K2 getting it out of a good percent of the atmosphere (over 28K feet) before it's released. The plan was more elaborate though involving high energy ground based lasers tracking it and flashing H2O to supercritical steam thus providing thrust in addition to its initial kinetic energy. This was push mass in to Lagrangian points not just LEO.

There's not much development around K2 so no one would be bothered by the shock-wave.

Because you're not as concerned with the mass of the projectile you could surround the satellite by some sort of heavy sabot to protect it in atmospheric flight.

The problem I have with this is, do we really want all this stuff up in orbit? There's enough junk up there as it is.

Niven used this launch system in Ringworld,or was it for landing

He described the rings as being for decelerating a ship returning to the Ringworld. For those who don't know, the Ringworld is a ring 93 million miles in radius - one Earth orbit - which would make it 600 million miles long. It started with the mass of a Jupiter sized planet, and it's a million miles wide, about a thousand meters thick. It has three million times the surface area of the Earth. It was built by my species (literary spoiler reference to my screen name).

More precisely the rings would actually have been for accelerating or decelerating any returning space ship, as needed, to match the Ringworld spin rate (770 miles/second). The ship would then just maneuver over to a landing platform once it's matched the spin rate. For "launching" the ship, already traveling at the Ringworld spin velocity while sitting on the platform, would just be "dropped" through a trap door, ala one of these satellites being flung into space and float away at roughly 1 gravity.

The superconducting rings were made from scavanged parts of the original designs steering jets, needed to keep the ring stable with it's star at the center of it's spin. The Ringworld inhabitants who built the system didn't realize that they were endangering the entire Ringworld when they stole the parts for their system and for their Bussard Ramjet space ships, which also used the superconductors. That stuff gets covered in Ringworld Engineers, Ringworld Throne and Ringworld's Children. He also talks about the engineering of Ringworld in a neat essay, Bigger Than Worlds.

Can you tell I'm a bit obssessed? <g>

Protectors were actually afraid of Puppeteers, as well. They knew that they could pose threat to their species and, given the chance, would have wiped them out. That factored into Ringworld Throne to a significant degree. That was part of what the "Brennan Monster" was doing in fighting the Protectors. He didn't want anything to happen to Humans, but he saw other species as potentially beneficial to man, too. They didn't know about any other species yet (Phssthpok was the first alien they'd encountered as of the novel Protector) but once Brennan was changed he would have been able to reason out the existence of other species.

My favorite thing about the Ringworld books is probably the true story where Niven explained why he wrote the second book, Ringworld Engineers. He got emails from all over picking at the engineering of his original concept, including one from Freeman Dyson himself! He also tells the story of being at a convention in Boston and having an entire engineering class from MIT start chanting during his speech "the Ringworld is unstable" over and over. They'd done a semester examining the whole thing. He had to incorporate all of this into the second novel to fix the things he'd overlooked in the first one. That's where the attitude jets came from, for example.

Stories like that are why I enjoy the mega collections of Niven's stuff, the one with the essay "Bigger than Worlds," Playgrounds of the Mind, and the other one, N-Space. They contain some short stories, some excerpts from the big novels, some essays (including Man of Steel, Woman of Kleenex) but also lots of little stories. The one about "Speaker to Seafood" is a riot.

I met Larry Niven at a SF convention several years ago and spent the whole weekend with him and Jerry Pournelle in the hospitality suite getting drunk. Pournelle and I knew each other from years of attending the same computer conventions, so he let me into the inner circle, even though it was my first SF con. Very fun people. I even got to discuss with him some flaws I saw in the back story for Protector, where his supposed biological link just doesn't stand up to what we know now scientifically about our species and other species on Earth. I provided him an alternative biological explanation for the similarities between humans and Protectors, that even added in a connection back to the Slaver/Tnuctip galaxy wide war he alludes to in his other Known Space stories. To explain why the "wrong" version of the story was in the book Protector I told him he could simply say that Brennan, the only source of the info in the novel, had lied to protect humans from knowing the truth, which would mess with their natural development. He's never used it, but he told me he liked it.

Oh, and the Tnuctip created the sunflowers for their masters, the Slavers. The Tnuctip were master genetic engineers whom the Slavers controlled with their mental powers, that is until the Tnuctip rebelled and the Slavers wiped out all intelligent life everywhere in the galaxy, including themselves, by unleashing their super weapon. That was several billion years ago, however. We came along later.

Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.