I had to smile when I saw the picture. That’s exactly what I designed 20 years ago : a 1/2 mile diameter ring EMSL cannon. It was basically a bicycle wheel structure on an incline. Track was made of silver(best conductor and HTS metal for mag-lev). Outer rim was like a highway lane w/steel rebar. Hi density concrete between Ag track and rim. Short Q tail w/15 chambers separated by movie film(advance one frame after projectile punches thru, to maintain internal vacuum)for 1 psi differentials.
The projectile(10kg)had a flat diamond cross section(stiletto)and was basically a frozen beer can. 13.75 minutes at 1g acceleration to reach 5 mps injection velocity. Lithium pore or cast-in Li beads in the nose(3 seconds ablation heating at hypersonic speed). Several projectiles at once in the ring = machine gun burst.
I figured about 2 shuttle loads to LEO every day. Since 1# = 4 KW in LEO and with between 1% to 10% system efficiency, it would be about postage rates(40 cents/oz)to put mass into LEO. I had it all thought out 20 years ago(1988)but NASA wanted nothing to do with EMSL, it would have shown them up as bumbling oafs instead of ROCKET SCIENTISTS with their horribly inefficient chemical rockets.
So, Reagan’s plan of bankrupting the USSR by trying to keep up with star wars development funding WORKED, thus SDI funding all but disappeared, as did EMSL as a superior idea. Once again...vested interests....
Okay, but how long... for the beer to unfreeze?