I had an odd thought. Suppose I have a ball of gasoline inside a ball of O2 in free space. The ball and I start in the same inertial frame with respect to some planet. The ball starts accelerating. The ball reaches the kinetic energy enough for the combustion of gasoline[I think this will depend on the mass of gas present, but suppose that it is really high and such that the velocity is say 95% the speed of light]. From my frame of reference the ball would explode right?