Why was there a gap between the apparent limb of Jupiter and the plumes or fireballs in the Hubble images?
It is important to distinguish between the limb of Jupiter and the terminator (or sunrise line) which was several degrees closer from our perspective. In fact, the Hubble images show the luminescent fireball above the dark limb of Jupiter only 1-2 minutes after the fragment G impact. The apparent gap in this image is between the limb and the terminator. A few minutes later, the fireball has risen high enough to be in sunlight. There is also a gap due to the shadow of Jupiter on the plume. The debris cloud that makes up the plume has risen into sunlight as we predicted in our “Watching for Fireballs” paper (EOS, July 5). The earth, Jupiter and the Sun were not in a straight line at the time of impact, so the plume had to rise hundreds of kilometers higher than the limb to reach sunlight.
