To fire a rail gun, one needs an electrical power supply which can produce high voltage and high current.

Electricity in lightning is high voltage, and high current.

Since the power requirements and power supply are similar, they ought to be compatible.

Given the large amount of energy in a single lightning bolt, we might conceive of this as being a space gun.

Given the unpredictability of lightning, and the high rate of acceleration, payloads should be low priority (it should be OK to sit on the launcher for weeks, waiting for a storm), and very rugged.
-- goldbb, Apr 28 2010

Plasma Rail Railgun Plasma_20Rail_20Railgun
"I propose that the rails be replaced with bolts of lightning." [bungston, Apr 29 2010]

To launch a payload into orbit you need to get to about 17,000 miles per hour. Since I think you're suggesting using a lightning bolt to provide the power for this acceleration via a rail gun, that means the acceleration to 17,000 mph would happen in the split second duration of that lightning bolt.

All this while overcoming the friction of the atmosphere which is hard as a wall at that speed.

You'd have a very unhappy payload even if you did have enough power to get something going that fast. I know there was great difficulty hardening payloads that were shot from the famous "space gun" during the HARP project. I'll see if I can find a good link.
-- doctorremulac3, May 01 2010



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