Henschman, do you know what the PK-3000 was?
It was an insterstellar-capable spacecraft actually designed by Soviet engineers under Saharov Sakharov (this should give you hints as to how it was supposed to operate). Both the USSR and the US designed spacecraft that, if needed, could be used to introduce exploratory interstellar and routine intra-system planet. Some of these spacecraft and propulsion systems were actually tested successfully, but construction was shut down for political, not technical, reasons.
I can fully imagine an Alien-Brezhnev in an Alien-USSR that would sign off on the building on a PK-3000 or identical technology in their version of the 1960's.
Ah, the Russian "orionski". For those that don't know, Sakharov was the father of the russian hydrogen bomb (the equivalent of teller (well, more accurately ulam, as ulam was the brains)), and advanced many areas of high energy applications. I do believe the Orion concept was first formulated in the US (dyson I believe), and then by Sakharov. Neither would be truly capable of interstellar (even primitive ~1% c) travel using 1960's tech, or even current (the yield to mass of the pulse units required (at the yield needed, we can achieve the requisite on much larger devices, but not on the 10-50kt size needed) devices, given the inert mass needed. For a hardened unmanned ship, it's potentially possible to do primitive interstellar with current tech, but would be really difficult (and require effectively the same aggregate tonnage yield as our entire stockpile). The politics involved that killed it on both sides was the nuclear weapons in space ban, and the discovery of HEMP, as it is relatively easy to determine that breaking orbit would cause major issues if not done conventionally, and thus nearly double the mass needed to be orbited. After that, it was a question of funding...even a primitive unmanned system for 1% c woud cost several hundred billion dollars at least in today's currency--a non-starter. When I was working interstellar precursor for NASA, we were concentrating on compact long life fission reactors driving MPD or VASIMIR thrusters for early concepts, and (when I was working for rocketdyne advanced projects) a dense plasma focus fusion thruster, the latter which could give you 1-3%c in <5yr burn time, with a 10-20ton payload, and <200 tons launch mass...the goal was a program cost of <10-20 billion. (and 1/3rd of a light-year in 25 years).
The technology to do so was at or slightly beyond state of the art (still is), so there are technological limits if one attempts to do such a mission within the confines of even theoretical funding (ie the entire NASA exploration budget). To put in perspective, that DPF thruster system I designed produced nearly 20-50 MEGAWATTS of hard x-rays from the thruster, and in order to keep it from melting (it was a 2-3 gigawatt thruster about the size of a gallon jug), we needed 100kg of liquid hydrogen PER SECOND just for cooling the thruster and x-ray shield. While we had detailed plans on how to build it (I'm quite proud of my pulse power system I designed for it), it was (and still is) low TRL.
So...anyone have a few 10's of billions? I want to send stuff to the stars!
