Fragment K - no optical flash, yes optical cloud
CCD images were obtained with an R filter from Perth Observatory with 3-second exposures and about 2/3-second dead time covering Jupiter's limb, Io, and the expected position of Europa (in eclipse) from Jul 19 10:00 UT to Jul 19 10:30 UT. Io was completely saturated. In the raw data there was no hint of a flash reflected from Europa, nor was there any flash at the limb of Jupiter.
Starting at Jul 19 10:35 UT, images with a narrow methane absorption filter at 8930A showed a definite prominence above the apparent limb of Jupiter, having approximately the same surface brightness as other portions of that latitude belt. Note that this is probably already on the front side of Jupiter as the limb in the continuum is well above the limb in the strong methane filter. This suggests that condensation occurs very rapidly after the fireball is ejected.
Mike A'Hearn for the Perth-Maryland team. (R. Martin, D. Wellnitz, students from WA)