How do I acquire a vector from an ephemeris or a two line element set?
Easy. From the “Select Spacecraft” pull down menu, simply select the ephemeris you wish to use (usually ISS or SHUTTLE). NASA SkyWatch will return the first vector in the ephemeris. If you select a satellite other than ISS or the space shuttle, a GSFC two line element set will be retrieved. In either case, the threshold time to begin searching for sightings will default to your system clock time.
