The Iffy: Superman's Propulsion System
When Superman was first conceived, he didn't so much fly as jump. Because the gravitational field of Earth was so much weaker than Krypton, he looked like he was flying, just as the Apollo astronauts were able to bounce around on the moon. Since then he's been capable of some much more advanced aerial acrobatics, such as hovering midair and orbiting the Earth all fast-like, without any obvious propulsion system. The standard theory is that Kryptonians have some mutation that allows them to manipulate gravity to their will. Indeed, one of the keynote scenes of Man of Steel shows Superman placing his fist on the ground and seemingly altering his own gravimetric field. Yeah... but how? Can he manipulate the inertia of his own mass (and the matter he comes into contact with) at both the atomic and cosmic scales? Can he screw with magnetism in addition to gravity? Can KRYPTONIAN PIGS FLY? Please Kal-El, last son of Krypton, enlighten us about your gift.