  Technological realities limit terrestrial quantum key distribution (QKD) to
single-link distances of a few hundred kilometers. One promising avenue for
global-scale quantum communication networks is to use low-Earth-orbit
satellites. Here we report the first demonstration of QKD from a stationary
transmitter to a receiver platform traveling at an angular speed equivalent to
a 600 km altitude satellite, located on a moving truck. We overcome the
challenges of actively correcting beam pointing, photon polarization and
time-of-flight. Our system generates an asymptotic secure key at 40 bits/s.
