STS103-713-048 (19-27 December 1999) --- Astronauts Steven L. Smith, and John M. Grunsfeld, appear as small figures in this wide scene photographed during extravehicular activity (EVA). On this space walk they are replacing gyroscopes, contained in rate sensor units (RSU), inside the Hubble Space Telescope. A wide expanse of waters, partially covered by clouds, provides the backdrop for the photograph.