The possibility of investigating the solar corona from Earth orbits is cons
idered. The results of observations of some atmospheric optical phenomena,
viz., noctilucent clouds, stratospheric aerosol layers, and Fresnel reflect
ion from the Earth's atmosphere, are discussed. An hypothesis regarding the
nature of the apparent magnification of the atmosphere in observations fro
m space is advanced. (C) 2000 The Optical Society of America.