Asteroids in this region, near the ecliptic and outside Earth's orbit, are at their brightest as seen from Earth and thus most likely to be discovered and followed. Objects come and go, showing in the viewer only while inside ten LD or under active observation (and leave trails only when inside 20 LD). Viewer frame rate seems smoothest at the "good" speed setting, but your experience may differ. Single-clicking anywhere on the skychart acts like hitting the [Run] button. This Asteroid/Comet Connection.