Apologies for the long question.
With all the speculation surrounding the newly-discovered Earth-sized planets a "mere" 40 ly distant, I'm revisiting earlier musings on ways to send interstellar probes on a timescale that's useful (e.g. less than thousands of years).
If we were going to use some sort of linear accelerator or rail gun (I don't understand the differences well enough to know which is best applied) to "shoot" a sub-kilogram scale probe at another solar system, how do you go about calculating the "muzzle velocity" achieved using factors for energy input and length? I suppose the "sub-kilogram" part isn't that relevant, except to set the scope of the accelerated mass variable, but I wanted to establish the limits around what I'm trying to discover.
Associated questions are:
- For the amount of energy it would take, do we have a good way to use it in orbit? For instance, if we put a hectare of solar panels in orbit, and use them to charge an ultracapacitor, is that sufficient technology to power our accelerator?
- Where is a good place to locate such an accelerator?
- How much acceleration force (gees) is going to be applied to the probe for a given length of "barrel" and "muzzle velocity"?