All three Apollo 17 astronauts sketched a ''lunar horizons glow,'' seen from orbit above the Moon. It is shown that the shape of the glow is compatible with scattering of sunlight off a gas or dust at high altitudes above the Moon. Our mathematical modeling best simulates the glow with submicron dust grains whose spatial density varies with altitude above the Moon as exp(-H/Hs), where Hs is in the range of 5 to 20 km. These dust grains are probably electrically charged and ejected the lunar surface by local electric fields. ¿American Geophysical Union 1991