Don Barry's Earth Satellite Ephemeris Service 8/96 ESA Hipparcos Page 7/97 pg 34 Goddard Space Flight Center Next Generation Space Telescope 3/97 Satellite Observing Resource Page 8/96 Skyshow 8/96 Titan's Atmosphere and Evolution Through Disk-Resolved Spectroscopy using the Hubble Space Telescope, by George Lewycky 6/97 pg 100 TRAKSAT (Satellite Tracking Software) 7/97 pg 72 Ulysses Solar Observer 8/96 Visual Satellite Observers Home Page 8/96 Lou William's Predictions Page 8/96
Note: See also European Space Flight Agencies.