G impact from MSSSO
This exposure was sufficiently long that the image is saturated on the detector (making it look pretty spectacular). The Keck image also is quite impressive. There was a lot of flux from this chunk.
Optical CCD image after Fragment G impact
HST Color Photo Fragment G impact site
Note the morphology of this complex. The central black spot represent the initial impact. There is then a ring around that spot, which presumably is some kind of shock feature. Finally not the obvious fan of dark material to one side which is the ejecta blanket. The overall size of this feature is like that of the Great Red Spot. I think the ejecta blanket is probably larger in scale than was anticipated.
Comparative Wavelength Morphology of G impact site from HST
Once again, this illustrates that the features are dark (low reflectivity) in the visible and bright in the infrared presumably because you are seeing, through these holes, to deeper (warmer) levels of the Jovian atmosphere