Rockets are expensive, complex, bad for the environment and prone to occasionally exploding – so alternative launch technologies are popping up to reduce their use. We wrote about SpinLaunch's remarkable kinetic launch system earlier this week, which spins a rocket up to incredible speeds on the end of a long, carbon-fiber arm in a vacuum chamber, then releases it skyward at speeds up to and over Mach 6. Then another company dropped us a line, to show us a far simpler approach it says can get launch vehicles and ruggedized electronic cargo off the ground at nearly three times that...