ABSTRACT
The resolution of an Earth-bound telescope peering at celestial objects through the Earth's atmosphere is limited to 1". This is because atmosperic turbulence bends incoming wavefronts of light through angles of the order of 1". However a telescope mounted on an orbiting Earth satellite looking down at objects on the ground can very nearly achieve the diffraction limited resolution of the telescope. Assuming that the turbulence arises in a layer about 20 km above the ground show how this comes about.
